HMC983LP5E

v02.0112

DC - 7 GHz FRACTIONAL-N DIVIDER

AND FREQUENCY SWEEPER

Typical Applications Features (Continued)

The DC - 7 GHz FRACTIONAL-N DIVIDER is suitable Integrated Frequency Sweeper
for:
- Linear, Coherent Sweeps
Frequency Dividers & Detectors - SMT

• Test Equipment - 2-Way, 1-Way, & User Defined Sweep Modes

• Portable Instruments - Automatic or Triggered
- Programmable Seed
• High Performance Fractional-N Frequency Synthe- -SPI & External Triggering
sizers with Ultra Low Spurious 5-GPIO’s, can be used for External DSM
• Stand-Alone Divider and/or Delta-Sigma Modulator Cycle Slip Prevention Support with PFD Chip
Features (HMC984LP4E)
Wideband: DC - 7 GHz Input Differential VCO Input & Divider Output
-20-bit Frequency Divider
Programmable Output Current Control:
Low Noise: -160 dBc/Hz -5 mA to 17.5 mA Open Collector Output Driver
Low Spurious: Largest Spurious - 95 dBc 32 pin, 5 x 5 mm, LP5 Package
48-bit 100 MHz Delta-Sigma Modulator (DSM)
- Configurable DSM Size
- Programmable Seed
- Phase Step
General Description
DC - 7 GHz FRACTIONAL-N DIVIDER is a fractional
Functional Diagram
frequency divider targeted for fractional-N frequency
synthesis, and stand-alone low noise frequency
divider applications that require exceptional spurious
performance.
Although the DC - 7 GHz FRACTIONAL-N DIVIDER
can work with any VCO and/or compatible Phase
Detector, best performance and features will be
achieved when paired with the companion part, the
HMC984LP4E.
Fabricated in SiGe BiCMOS process, the
DC - 7 GHz FRACTIONAL-N DIVIDER features a
48-bit Delta Sigma Fractional Modulator (DSM) with
programmable phase accumulator size, enabling
precise control of frequency step size and resolution.
Integrated DSM can generate frequencies with nearly
0 Hz frequency error. The DSM also includes a built-in
programmable frequency sweep capability, with
various automatic and user defined sweep modes and
triggering options, including hardware trigger pin, or
SPI trigger with optional delayed trigger.
DC - 7 GHz FRACTIONAL-N DIVIDER is a versatile
part capable of various configurations. It has 5
general purpose I/Os (GPIOs). DSM outputs are
made available from the GPIO port, enabling the
DC - 7 GHz FRACTIONAL-N DIVIDER to import and/
or export DSM sequences for various configuration
options.
DC - 7 GHz FRACTIONAL-N DIVIDER divider outputs
are differential, open collector with programmable
Product covered by US and Foreign Patents including US Pat. No. 8,531,217.
current to accommodate different off-chip loads.
Information furnished by Analog Devices is believed to be accurate and reliable. However, no
For price, delivery and to place orders: For price, 2delivery, and to placeChelmsford,
orders: Analog MA
Devices, Inc.,
responsibility is assumed by Analog Devices for its use, nor for anyHittite Microwave
infringements Corporation,
of patents or other Elizabeth Drive, 01824
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106
rights of third parties that may result from its use. Specifications subject to change without notice. No
Phone: 978-250-3343 Fax: 978-250-3373 Phone: Order781-329-4700
On-line at www.hittite.com
1 license is granted by implication or otherwise under any patent or patent rights of Analog Devices.
Application
• Order online at www.analog.com
Support: Phone: 1-800-ANALOG-D
Trademarks and registered trademarks are Application Support:
the property of their Phone: 978-250-3343
respective owners. or apps@hittite.com
 HMC983LP5E
v02.0112

DC - 7 GHz FRACTIONAL-N DIVIDER

AND FREQUENCY SWEEPER

Table 1. Electrical Specifications

TA = +25 °C, AVDD, VCCPS, VCCHF, VDDM, DVDD = 3 V ± 10%; VPPBUF = 5 V ± 10%; GND = 0 V

Frequency Dividers & Detectors - SMT

Parameter Conditions Min. Typ. Max. Units

RF Input Characteristics

RF Input Frequency range DC 7 GHz

RF Input Sensitivity -15 -10 0 dBm

RF Input Capacitance External Match Recommended 3 pF

Divider Range (20-bit)

Integer Mode 32 1,048,575

Fractional Mode 36 1,048,571

Divider Output Characteristics

Output Buffer Current Programmable in 2.5 mA Steps 5 12.5 17.5 mA

Output Voltage Swing Single- Ended, Vpullup = 5 V 0.75 1 2 V

Output Frequency Range

DC 150
Integer Mode MHz
Mode A and Mode B DC 125
Fractional Mode

Phase Noise 50 MHz PFD, 6 GHz Input, Integer Mode -160 dBc/Hz

Largest observed at 10 kHz Fractional

Fractional Spurious -95 -85 dBc
Offset from Integer Boundary

Logic Inputs

Input High Voltage (VIH) DVDD-0.4 V

Input Low Voltage (VIL) 0.4 V

Logic Outputs

Output High Voltage (VOH) DVDD-0.4 V

Output Low Voltage (VOL) 0.4 V

DC Load 1.5 mA

Serial Port Clock Frequency Main SPI and AUXSPI 30 MHz

Power Supplies

Analog Supplies. AVDD should be equal

AVDD, VCCPS, VCCHF 2.7 3 3.3 V
to DVDD.

VPPBUF Output Buffer Supply. 4.5 5 5.5 V

VDDM, DVDD Digital Supplies 2.7 3 3.3 V

Current Consumption

Integer Mode / Fractional Mode

IDD - Total Current Consumption 104 / 122 mA
(50 MHz Divider Output)

I - AVDD (AVDD Current, 3 V) Integer Mode / Fractional Mode 5/5 mA

I - VCCPS (VCCPS Current, 3 V) Integer Mode / Fractional Mode 79 / 79 mA

I - VCCHF (VCCHF Current, 3 V) Integer Mode / Fractional Mode 8/8 mA

I - VDDM (VDDM Current, 3 V) Integer Mode / Fractional Mode 11 / 11 mA

I - DVDD (Total DVDD Current, 3 V) Integer Mode / Fractional Mode 1 / 19 mA

I - VPPBUF (Total VPPBUF Current,

5 uA
5 V)

Information furnished by Analog Devices is believed to be accurate and reliable. However, no

For price, delivery and to place orders: For price, 2delivery, and to placeChelmsford,
orders: Analog MA
Devices, Inc.,
responsibility is assumed by Analog Devices for its use, nor for anyHittite Microwave
infringements Corporation,
of patents or other Elizabeth Drive, 01824
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106
rights of third parties that may result from its use. Specifications subject to change without notice. No
Phone: 978-250-3343 Fax: 978-250-3373 Phone:
license is granted by implication or otherwise under any patent or patent rights of Analog Devices.
Order781-329-4700
On-line at www.hittite.com
• Order online at www.analog.com 2
Trademarks and registered trademarks are Application Support:
the property of their Phone: 978-250-3343
respective owners. Application Support: Phone: 1-800-ANALOG-D
or apps@hittite.com
 HMC983LP5E
v02.0112

DC - 7 GHz FRACTIONAL-N DIVIDER

AND FREQUENCY SWEEPER

Figure 1. RF Input Sensitivity [1] Figure 2. Output Phase Noise, 6 GHz

Input Frequency [2]
40 -60
Maximum Input Power Limit 100 MHz Output Frequency Frac Mode A
Frequency Dividers & Detectors - SMT

20 -80
100 MHz Output Frequency Frac Mode B
RF INPUT POWER (dBm)

PHASE NOISE (dBc/Hz)

-100
0
Recommended Operating Range
-120
-20
-140
-40
RF Input Signal Phase Noise
+27 C -160
+85 C
-60 Minimum Input Power Limit -40 C
-180
100 MHz Output Frequency Integer Mode

-80 -200
2 3 4 5 6 7 8
0 2000 4000 6000 8000 10000 10 10 10 10 10 10 10
RF INPUT FREQUENCY (MHz) OFFSET FREQUENCY (Hz)

Figure 3. Output Phase Noise with 6 GHz Figure 4. Time Domain 10 MHz Output,
Input in Integer Mode [3] 6.5 GHz Input [4]
-60 5.5

-80 142 MHz Output Frequency

divCkPFDp Pin Output
OUTOUT VOLTAGE (V)
PHASE NOISE (dBc/Hz)

-100
RF Input Signal Phase Noise 5

-120
100 MHz Output Frequency
-140

4.5
-160

50 MHz Output Frequency

-180
divCkPFDn Pin Output
Calculated Phase Noise
-200 4
2 3 4 5 6 7 8
10 10 10 10 10 10 10 0 50 100 150 200 250 300 350
OFFSET FREQUENCY (Hz) TIME (ns)

Figure 5. Time Domain 18 MHz Output, Figure 6. Time Domain 35 MHz Output,
6.5 GHz Input [4] 6.5 GHz Input [4]
5.5 5.5

divCkPFDp Pin Output divCkPFDp Pin Output

OUTPUT VOLTAGE (V)
OUTPUT VOLTAGE (V)

5 5

4.5 4.5

divCkPFDn Pin Output divCkPFDn Pin Output

4 4
0 50 100 150 200 0 20 40 60 80 100

TIME (ns) TIME (ns)

[1] The maximum and minimum levels indicate operational limits of the
DC - 7 GHz FRACTIONAL-N DIVIDER. Performance may degrade with input power greater than
0 dBm for frequencies higher than 6500 MHz.
[2] Due to Delta Sigma modulation in fractional mode, the output phase noise peaks at frequency offset of fout/2 from the output. Agilent MXG N5182A
used as a signal source.
[3] Rohde & Schwarz SMBV100A used as a signal source.

Information furnished by Analog Devices is believed to be accurate and reliable. However, no

For price, delivery and to place orders: For price, 2delivery, and to placeChelmsford,
orders: Analog MA
Devices, Inc.,
responsibility is assumed by Analog Devices for its use, nor for anyHittite Microwave
infringements Corporation,
of patents or other Elizabeth Drive, 01824
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106
rights of third parties that may result from its use. Specifications subject to change without notice. No
Phone: 978-250-3343 Fax: 978-250-3373 Phone: Order781-329-4700
On-line at www.hittite.com
3 license is granted by implication or otherwise under any patent or patent rights of Analog Devices.
Application
• Order online at www.analog.com
Support: Phone: 1-800-ANALOG-D
Trademarks and registered trademarks are Application Support:
the property of their Phone: 978-250-3343
respective owners. or apps@hittite.com
 HMC983LP5E
v02.0112

DC - 7 GHz FRACTIONAL-N DIVIDER

AND FREQUENCY SWEEPER

Figure 7. Time Domain 124 MHz Output, Figure 8. Time Domain 66 MHz Output,
6.5 GHz Input [5] 6.5 GHz Input [5]
5.5 5.5

Frequency Dividers & Detectors - SMT

divCkPFDp Pin Output divCkPFDp Pin Output
OUTPUT VOLTAGE (V)

OUTPUT VOLTAGE (V)

5 5

4.5 4.5

divCkPFDn Pin Output divCkPFDn Pin Output

4 4
0 5 10 15 20 25 30 0 10 20 30 40 50
TIME (ns) TIME (ns)

Figure 9. Time Domain 61 MHz Output, Figure 10. Time Domain 66 MHz Output,
6.5 GHz Input [5] 6.5 GHz Input [5]
5.5 5.5

divCkPFDp Pin Output divCkPFDp Pin Output

OUTPUT VOLTAGE (V)

OUTPUT VOLTAGE (V)

5 5

4.5 4.5

divCkPFDn Pin Output divCkPFDn Pin Output

4 4
0 10 20 30 40 50 0 10 20 30 40 50
TIME (ns) TIME (ns)

Figure 11. 10 MHz Output Swing vs Figure 12. 50 MHz Output Swing vs Buffer
Buffer Current [6] Current [6]
0.9 0.9
SINGLE-ENDED OUTPUT SWING (Vpp)
SINGLE-ENDED OUTPUT SWING (Vpp)

0.85 0.85

0.8 0.8

0.75 0.75

0.7 0.7

0.65 0.65

-40 C 0.6 -40 C

0.6
+27 C +27 C
0.55 +85 C 0.55 +85 C

0.5 0.5
12 13 14 15 16 17 18 12 13 14 15 16 17 18
OUTPUT BUFFER CURRENT (mA) OUTPUT BUFFER CURRENT (mA)

[4] Measured with 50 Ω impedance per line, integer Mode, 15 mA Output Buffer Current (Reg 0Fh[4:2]) selected
[5] Measured with 50 Ω impedance per line, integer Mode, 15 mA Output Buffer Current (Reg 0Fh[4:2]) selected

Information furnished by Analog Devices is believed to be accurate and reliable. However, no

For price, delivery and to place orders: For price, 2delivery, and to placeChelmsford,
orders: Analog MA
Devices, Inc.,
responsibility is assumed by Analog Devices for its use, nor for anyHittite Microwave
infringements Corporation,
of patents or other Elizabeth Drive, 01824
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106
rights of third parties that may result from its use. Specifications subject to change without notice. No
Phone: 978-250-3343 Fax: 978-250-3373 Phone:
license is granted by implication or otherwise under any patent or patent rights of Analog Devices.
Order781-329-4700
On-line at www.hittite.com
• Order online at www.analog.com 4
Trademarks and registered trademarks are Application Support:
the property of their Phone: 978-250-3343
respective owners. Application Support: Phone: 1-800-ANALOG-D
or apps@hittite.com
 HMC983LP5E
v02.0112

DC - 7 GHz FRACTIONAL-N DIVIDER

AND FREQUENCY SWEEPER

Figure 13. 100 MHz Output Swing vs

Buffer Current [7] Figure 14. Input Return Loss
0.9 0
SINGLE-ENDED OUTPUT SWING (Vpp)

0.85
Frequency Dividers & Detectors - SMT

0.8 -5

RETURN LOSS (dB)

0.75

0.7 -10

0.65

0.6 -40 C -15

+27 C
0.55 +85 C

0.5 -20
12 13 14 15 16 17 18 0 2000 4000 6000 8000

OUTPUT BUFFER CURRENT (mA) FREQUENCY (MHz)

Figure 15. Two Way Frequency Sweep, Figure 16. One Way Frequency Sweep,
50 MHz PFD [8] 10 MHz PFD and 10 Hz external trigger [8]
7000 7000

6900 6900
FREQUENCY (MHz)
FREQUENCY (MHz)

6800 6800

6700 6700

6600 6600

6500 6500

6400 6400
0 5 10 15 20 0 200 400 600 800 1000
TIME (ms) TIME (ms)

Figure 17. PLL Cycle Slip Prevention, Figure 18. PLL Cycle Slip Prevention,
100 MHz PFD [8] 50 MHz PFD [8]
7050 7050
CSP Enabled
7000 Reg0Eh[18:15] = 1h CSP Enabled
7000
PLL OUTPUT FREQUENCY (MHz)

PLL OUTPUT FREQUENCY (GHz)

Reg0Eh[18:15] = Fh
CSP Enabled
6950 6950 CSP Enabled
Reg0Eh[18:15] = 8h
Reg0Eh[18:15] = 5h
6900 6900

6850 Cycle Slip Disabled 6850

Cycle Slip Disabled

6800 6800

6750 6750

6700 6700
0 50 100 150 200 250 300 0 50 100 150 200 250 300
TIME (us) TIME (us)

[6] Measured with 50 Ω impedance per line. Buffer current is controled via Reg 0Fh[4:2].
[7] Measured with 50 Ω impedance per line. Buffer current is controled via Reg 0Fh[4:2].
[8] Measured with HMC983LP5E/HMC984LP4E chip set as fractional-N synthesizer. Crystal input frequency = 100 MHz, CP current = 2.5 mA, CP
offset current = 245 uA, Loop filter bandwidth = 87 KHz, DSM Mode B selected. Cycle Slip Prevention (CSP) is disabled in HMC984LP4E by setting
Reg 01h [4] = 0. Setting Reg 01h [4] = 1 enables CSP in the two chip PLL.
Information furnished by Analog Devices is believed to be accurate and reliable. However, no
For price, delivery and to place orders: For price, 2delivery, and to placeChelmsford,
orders: Analog MA
Devices, Inc.,
responsibility is assumed by Analog Devices for its use, nor for anyHittite Microwave
infringements Corporation,
of patents or other Elizabeth Drive, 01824
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106
rights of third parties that may result from its use. Specifications subject to change without notice. No
Phone: 978-250-3343 Fax: 978-250-3373 Phone: Order781-329-4700
On-line at www.hittite.com
5 license is granted by implication or otherwise under any patent or patent rights of Analog Devices.
Application
• Order online at www.analog.com
Support: Phone: 1-800-ANALOG-D
Trademarks and registered trademarks are Application Support:
the property of their Phone: 978-250-3343
respective owners. or apps@hittite.com
 HMC983LP5E
v02.0112

DC - 7 GHz FRACTIONAL-N DIVIDER

AND FREQUENCY SWEEPER

Table 2. Pin Descriptions

Pin Number Function Description Interface Schematic

Frequency Dividers & Detectors - SMT

1, SENb
2, SDI Main SPI Data Input
3 SCK

4, D1 GPIO bit 1
5 D0 GPIO bit 0

6, AUX_SCLK Auxiliary SPI Clock Output

7, AUX_SENb Auxiliary SPI Enable
8 AUX_SDO Auxiliary SPI Data Output

9 BIAS External Decoupling for Analog Bias Circuits

3 Volt Power Supply Pin for Internal Reference Cur-
10 AVDD
rent Sources

11 VCCPS 3 Volt Power Supply Pin for Prescaler

12, VCOIN, Negative Pin for Prescaler Differential Input, AC-Coupled

13 VCIOP Positive Pin for Prescaler Differential Input, AC-Coupled

14 VCCHF 3 Volt Power Supply Pin for Prescaler Input Buffer

15 VPPBUF 5 Volt Power Supply Pin for Divider Output Buffer

16 N/C No Connect Pin

Information furnished by Analog Devices is believed to be accurate and reliable. However, no

For price, delivery and to place orders: For price, 2delivery, and to placeChelmsford,
orders: Analog MA
Devices, Inc.,
responsibility is assumed by Analog Devices for its use, nor for anyHittite Microwave
infringements Corporation,
of patents or other Elizabeth Drive, 01824
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106
rights of third parties that may result from its use. Specifications subject to change without notice. No
Phone: 978-250-3343 Fax: 978-250-3373 Phone:
license is granted by implication or otherwise under any patent or patent rights of Analog Devices.
Order781-329-4700
On-line at www.hittite.com
• Order online at www.analog.com 6
Trademarks and registered trademarks are Application Support:
the property of their Phone: 978-250-3343
respective owners. Application Support: Phone: 1-800-ANALOG-D
or apps@hittite.com
 HMC983LP5E
v02.0112

DC - 7 GHz FRACTIONAL-N DIVIDER

AND FREQUENCY SWEEPER

Table 2. Pin Descriptions (Continued)

Pin Number Function Description Interface Schematic
Frequency Dividers & Detectors - SMT

17, divCkPFDn, Negative Pin for Open Collector Divider Output Driver
18 divCkPFDp Positive Pin for Open Collector Divider Output Driver

19 VDDM 3V Supply Pin for Digital Section of the Frequency Divider

20, D2, GPIO bit 2,

21, D3, GPIO bit 3,
22 D4 GPIO bit 4

Gate Control (Output) to request TCXO Clock Export from

23 REF_Eno
HMC984LP4E

24, CHIP1, Chip Address Pin 1,

25, CHIP2, Chip Address Pin 2,
26 CHIP3 Chip Address Pin 3

27, 30 DVDD 3V Power Supply for Digital

28, DNSAT, VCO Saturation Input flag from HMC984LP4E Chip

Information furnished by Analog Devices is believed to be accurate and reliable. However, no

For price, delivery and to place orders: For price, 2delivery, and to placeChelmsford,
orders: Analog MA
Devices, Inc.,
responsibility is assumed by Analog Devices for its use, nor for anyHittite Microwave
infringements Corporation,
of patents or other Elizabeth Drive, 01824
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106
rights of third parties that may result from its use. Specifications subject to change without notice. No
Phone: 978-250-3343 Fax: 978-250-3373 Phone: Order781-329-4700
On-line at www.hittite.com
7 license is granted by implication or otherwise under any patent or patent rights of Analog Devices.
Application
• Order online at www.analog.com
Support: Phone: 1-800-ANALOG-D
Trademarks and registered trademarks are Application Support:
the property of their Phone: 978-250-3343
respective owners. or apps@hittite.com
 HMC983LP5E
v02.0112

DC - 7 GHz FRACTIONAL-N DIVIDER

AND FREQUENCY SWEEPER

Table 2. Pin Descriptions (Continued)

Frequency Dividers & Detectors - SMT

Pin Number Function Description Interface Schematic

29 UPSAT Reference Saturation Input flag from HMC984LP4E Chip

31 CEN Chip Enable

32 SDO Main SPI Data Output

Information furnished by Analog Devices is believed to be accurate and reliable. However, no

For price, delivery and to place orders: For price, 2delivery, and to placeChelmsford,
orders: Analog MA
Devices, Inc.,
responsibility is assumed by Analog Devices for its use, nor for anyHittite Microwave
infringements Corporation,
of patents or other Elizabeth Drive, 01824
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106
rights of third parties that may result from its use. Specifications subject to change without notice. No
Phone: 978-250-3343 Fax: 978-250-3373 Phone:
license is granted by implication or otherwise under any patent or patent rights of Analog Devices.
Order781-329-4700
On-line at www.hittite.com
• Order online at www.analog.com 8
Trademarks and registered trademarks are Application Support:
the property of their Phone: 978-250-3343
respective owners. Application Support: Phone: 1-800-ANALOG-D
or apps@hittite.com
 HMC983LP5E
v02.0112

DC - 7 GHz FRACTIONAL-N DIVIDER

AND FREQUENCY SWEEPER

Table 3. Absolute Maximum Ratings

Nominal 3V Supplies to GND -0.3 to 3.6 V Thermal Resistance (Rth)
(junction to ground paddle) 40 °C/W
Frequency Dividers & Detectors - SMT

Nominal 3V Digital Supply to 3V

-0.3 to +0.3 V
Analog Supply Reflow Soldering
Peak Temperature 260 °C
Nominal 5V Supply to GND (VPPBUF) -0.3 to 5.5 V
Time at Peak Temperature 40 s
divCkp, divCkn common mode DC VCCPS + 0.5 V min
ESD Sensitivity (HBM) Class 1B
VCOIP, VCOIN Single Ended AC 50 Ω
+ 7 dBm
Source
VCOIP, VCOIN Differential AC 50 Ω
+ 13 dBm
Source
Stresses above those listed under Absolute Maximum Ratings may
Digital Input Voltage Range -0.25 to DVDD + 0.5 V
cause permanent damage to the device. This is a stress rating only;
Minimum Digital Load 1 kΩ functional operation of the device at these or any other conditions
above those indicated in the operational section of this specification
Operating Temperature Range -40 °C to +85 °C
is not implied. Exposure to absolute maximum rating conditions for
Maximum Junction Temperature 125 °C extended periods may affect device reliability.
Storage Temperature -65 to +125 °C
ELECTROSTATIC SENSITIVE DEVICE
OBSERVE HANDLING PRECAUTIONS
Outline Drawing

NOTES:
[1] PACKAGE BODY MATERIAL: LOW STRESS INJECTION MOLDED PLASTIC
SILICA AND SILICON IMPREGNATED.
[2] LEAD AND GROUND PADDLE MATERIAL: COPPER ALLOY.
[3] LEAD AND GROUND PADDLE PLATING: 100% MATTE TIN.
[4] DIMENSIONS ARE IN INCHES [MILLIMETERS].
[5] LEAD SPACING TOLERANCE IS NON-CUMULATIVE.
[6] PAD BURR LENGTH SHALL BE 0.15 mm MAX. PAD BURR HEIGHT SHALL BE
0.25 m MAX.
[7] PACKAGE WARP SHALL NOT EXCEED 0.05 mm
[8] ALL GROUND LEADS AND GROUND PADDLE MUST BE SOLDERED TO PCB
RF GROUND.
[9] REFER TO HITTITE APPLICATION NOTE FOR SUGGESTED PCB LAND
PATTERN.

Package Information
Part Number Package Body Material Lead Finish MSL Rating [2] Package Marking [1]
H983
DC7-GHzFRACTIONAL-NDIVIDER RoHS-compliant Low Stress Injection Molded Plastic 100% matte Sn MSL1
XXXX
[1] 4-Digit lot number XXXX
[2] Max peak reflow temperature of 260 °C

Information furnished by Analog Devices is believed to be accurate and reliable. However, no

For price, delivery and to place orders: For price, 2delivery, and to placeChelmsford,
orders: Analog MA
Devices, Inc.,
responsibility is assumed by Analog Devices for its use, nor for anyHittite Microwave
infringements Corporation,
of patents or other Elizabeth Drive, 01824
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106
rights of third parties that may result from its use. Specifications subject to change without notice. No
Phone: 978-250-3343 Fax: 978-250-3373 Phone: Order781-329-4700
On-line at www.hittite.com
9 license is granted by implication or otherwise under any patent or patent rights of Analog Devices.
Application
• Order online at www.analog.com
Support: Phone: 1-800-ANALOG-D
Trademarks and registered trademarks are Application Support:
the property of their Phone: 978-250-3343
respective owners. or apps@hittite.com
 HMC983LP5E
v02.0112

DC - 7 GHz FRACTIONAL-N DIVIDER

AND FREQUENCY SWEEPER

Evaluation PCB

Frequency Dividers & Detectors - SMT

The circuit board used in the application should use RF circuit design techniques. Signal lines should have 50 Ohms
impedance while the package ground leads and exposed paddle should be connected directly to the ground plane
similar to that shown unless mentioned otherwise. A sufficient number of via holes should be used to connect the top
and bottom ground planes. The evaluation circuit board shown is available from Hittite upon request.

Table 4. Evaluation Order Information

Item Contents Part Number
DC - 7 GHz FRACTIONAL-N DIVIDER and HMC984LP4E PLL Chipset Evaluation PCB
USB Interface Board E K IT 0 1 -
Evaluation Kit
6’ USB A Male to USB B Female Cable DC-7GHzFRACTIONAL-NDIVIDER
CD ROM (Contains User Manual, Evaluation PCB Schematic, Evaluation Software)

Information furnished by Analog Devices is believed to be accurate and reliable. However, no

For price, delivery and to place orders: For price, 2delivery, and to placeChelmsford,
orders: Analog MA
Devices, Inc.,
responsibility is assumed by Analog Devices for its use, nor for anyHittite Microwave
infringements Corporation,
of patents or other Elizabeth Drive, 01824
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106
rights of third parties that may result from its use. Specifications subject to change without notice. No
Phone: 978-250-3343 Fax: 978-250-3373 Phone:
license is granted by implication or otherwise under any patent or patent rights of Analog Devices.
Order781-329-4700
On-line at www.hittite.com
• Order online at www.analog.com 10
Trademarks and registered trademarks are Application Support:
the property of their Phone: 978-250-3343
respective owners. Application Support: Phone: 1-800-ANALOG-D
or apps@hittite.com
 HMC983LP5E
v02.0112

DC - 7 GHz FRACTIONAL-N DIVIDER

AND FREQUENCY SWEEPER

Evaluation PCB Block Diagram

Frequency Dividers & Detectors - SMT

Information furnished by Analog Devices is believed to be accurate and reliable. However, no

For price, delivery and to place orders: For price, 2delivery, and to placeChelmsford,
orders: Analog MA
Devices, Inc.,
responsibility is assumed by Analog Devices for its use, nor for anyHittite Microwave
infringements Corporation,
of patents or other Elizabeth Drive, 01824
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106
rights of third parties that may result from its use. Specifications subject to change without notice. No
Phone: 978-250-3343 Fax: 978-250-3373 Phone: Order781-329-4700
On-line at www.hittite.com
11 license is granted by implication or otherwise under any patent or patent rights of Analog Devices.
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 HMC983LP5E
v02.0112

DC - 7 GHz FRACTIONAL-N DIVIDER

AND FREQUENCY SWEEPER

Theory of Operation
The DC - 7 GHz FRACTIONAL-N DIVIDER can be used in following configurations:
1. Fractional-N or Integer Mode RF Frequency Divider or Prescaler

Frequency Dividers & Detectors - SMT

2. Fractional-N Frequency Synthesizer with an appropriate Phase Detector and VCO
Primary target application of the DC - 7 GHz FRACTIONAL-N DIVIDER is to be used in conjunction with the
AND FREQUENCY SWEEPER as shown in Figure 19. Together these two components form a high performance, low
noise, ultra low spurious emissions fractional-N frequency synthesizer.

Figure 19. Typical Application of HMC984LP4E with HMC983LP5E to Form a Frequency Synthesizer
The DC - 7 GHz FRACTIONAL-N DIVIDER consists of the following functional blocks
1. RF Input Buffer
2. 7 GHz Frequency Prescaler and Multi Modulus Divider
3. 48-bit Configurable Fractional Delta Sigma Modulator
4. Bias Circuit
5. Differential Output Driver
6. Frequency Sweeper
7. Main Serial Port Interface
8. Auxiliary Serial Port Interface (Output Only)
9. General Purpose Digital IO
10. Power On Reset Circuit

RF Input Buffer
The RF input stage provides the path from the external VCO to the fractional RF Divider. The RF input path is rated
to operate nominally from DC to 7 GHz. The DC - 7 GHz FRACTIONAL-N DIVIDER RF input stage is a differential
common emitter stage with DC coupling, and is protected by ESD diodes as shown in Figure 20. RF input is not
matched to 50 Ω due to wide input frequency range. At low frequencies, a simple shunt 50 Ω resistor can be used
external to the package to provide a 50 Ω match. For better performance it is recommended to match the RF inputs
externally and provide differential drive from the VCO. In most applications the input is used single-ended into either
the VCOIP or VCOIN pin with the other input connected to ground through a DC blocking capacitor. The preferred
input level for best spectral performance is -10 dBm.

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orders: Analog MA
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Phone: 978-250-3343 Fax: 978-250-3373 Phone:
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 HMC983LP5E
v02.0112

DC - 7 GHz FRACTIONAL-N DIVIDER

AND FREQUENCY SWEEPER
Frequency Dividers & Detectors - SMT

Figure 20. RF Input Stage

RF Path Fractional-N Divider

The RF input buffer is followed by a high frequency prescaler and a multi modulus divider. The divider has been
designed for the best output phase noise and spurious performance in both fractional and integer mode. The
fractional-N divider can divide input frequencies from 32 to 220 -1 (1048575) in integer mode and from 36 to 220 -5
(1048571) in fractional-N mode. The divider output pulse width depends on the RF input period and is adjustable via
SPI setting (refer to Duty Cycle Setting in register Reg 00h Chip ID, Soft Reset, Read Register[14:12]). The output
pulse width recommended setting is 40% to 60% where possible. At low output frequencies it may not be possible to
set 50% duty cycle. In such cases the maximum pulse width setting is recommended.

Figure 21. Divider Path

Divider Output Buffer

The divider output is differential and the output buffer stage is an open collector amplifier with off-chip pull-up resistors.
Due to sharp rise and fall times at the divider output, the external path should be designed differentially using RF
techniques.
When DC - 7 GHz FRACTIONAL-N DIVIDER and AND FREQUENCY SWEEPER are operating together as a
frequency synthesizer, 50 Ω pull-up resistors are provided in AND FREQUENCY SWEEPER.
VPPBUF pin should be connected to 5 V power supply. This pin does not sink DC current and is only used to bias the internal
ESD diodes and to provide an appropriate voltage level for the phase detector chip (AND FREQUENCY SWEEPER).
The two possible interface configurations are shown in Figure 22 and Figure 23 below.
The rising edge of the HMC983LP5E divider output divCkPFDp and falling edge of divCkPFDn are conditioned and re-
synchronized for best spectral performance. The alternative edges are not This means for best spectral performance
the HMC983LP5E must be used with a PFD, not an analog mixer.

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Phone: 978-250-3343 Fax: 978-250-3373 Phone: Order781-329-4700
On-line at www.hittite.com
13 license is granted by implication or otherwise under any patent or patent rights of Analog Devices.
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 HMC983LP5E
v02.0112

DC - 7 GHz FRACTIONAL-N DIVIDER

AND FREQUENCY SWEEPER

Frequency Dividers & Detectors - SMT

Figure 22. Generic Divider Output Interface

Figure 23. Divider Interface with AND FREQUENCY SWEEPER

Chip Address Pins

The DC - 7 GHz FRACTIONAL-N DIVIDER has three SPI chip address pins (SPI address [2:0] = ‘CHIP3, CHIP2,
CHIP1’), which enable multiple DC - 7 GHz FRACTIONAL-N DIVIDER devices to use the same SPI bus. SPI chip
address bits are read at power up, or every time DC - 7 GHz FRACTIONAL-N DIVIDER is reset. By default, all three
pins are internally pulled to DVDD, thus there is no need to connect the pins to DVDD to set them to logic high. To
assign a ‘0’ to any chip address bit, the corresponding pin should be connected to ground.
When used on the same SPI bus together with the companion part (the AND FREQUENCY SWEEPER), to form a frequency
synthesizer, some SPI commands, such as changing the reference division ratio to the AND FREQUENCY SWEEPER
may also require an action by the DC - 7 GHz FRACTIONAL-N DIVIDER. In order to avoid the necessity to write
two separate SPI transfers to implement one command (one to configure AND FREQUENCY SWEEPER, and
the other one to configure the DC - 7 GHz FRACTIONAL-N DIVIDER), it is possible to write the SPI address of the
companion part (AND FREQUENCY SWEEPER) into Reg 09h of the DC - 7 GHz FRACTIONAL-N DIVIDER. In such
cases, the DC - 7 GHz FRACTIONAL-N DIVIDER is able to recognize an SPI command to the companion part (the
AND FREQUENCY SWEEPER) that requires its own action, and act accordingly to update its own corresponding

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Phone: 978-250-3343 Fax: 978-250-3373 Phone:
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 HMC983LP5E
v02.0112

DC - 7 GHz FRACTIONAL-N DIVIDER

AND FREQUENCY SWEEPER

registers. Writing DC - 7 GHz FRACTIONAL-N DIVIDER’s own chip address to the companion chip address register
Reg 09h will disable this feature.
Frequency Dividers & Detectors - SMT

Saturation Detection Input Pins DNSAT, UPSAT

When the DC - 7 GHz FRACTIONAL-N DIVIDER is operating with its companion chip the AND FREQUENCY SWEEPER
as a frequency synthesizer, it automatically detects large phase errors and tries to tune the VCO faster by using
its algorithm for cycle-slip prevention (CSP). The UPSAT and DNSAT provide indication which frequency is higher
(VCO or Reference) from the counterpart Phase Detector/Charge Pump (the AND FREQUENCY SWEEPER). The
CSP algorithm manipulates the RF Divider and the Phase Detector at appropriate intervals to lock faster. See
AND FREQUENCY SWEEPER data sheet for more details. These pins should be connected to ground if not used.

REF_Eno Pin
REF_Eno pin is a digital output pin that is used by the DC - 7 GHz FRACTIONAL-N DIVIDER to request crystal
oscillator clock from the Phase Detector / Charge Pump chip (the AND FREQUENCY SWEEPER).
The crystal oscillator clock is multiplexed on the DC - 7 GHz FRACTIONAL-N DIVIDER’s DNSAT pin. The internal
frequency divider, programmed in Reg 02h, is used to generate the actual reference frequency present at the phase
detector. The imported clock is only used to communicate through the AUXSPI. At all other times, the clock and the
local reference dividers are turned off.
In stand-alone applications, if the DC - 7 GHz FRACTIONAL-N DIVIDER is required to communicate through the
auxiliary SPI, the DC - 7 GHz FRACTIONAL-N DIVIDER will expect to receive the auxiliary SPI clock on DNSAT pin.
Setting Reg 04h[15] = 1 keeps the auxiliary SPI clock enabled on the DNSAT pin.

Multi Purpose Digital IO Pins D0, D1, D2, D3, D4 (GPIO Pins)
The five general purpose digital input/outputs can be used for various modes of operation as well as test/debugging
purposes. GPIO pins are enabled by writing Reg 01h[4] = 1 (GPIO master enable). Setting Reg 01h[4] = 0 places the
GPIO pins in tri-state high impedance mode.

GPIO pins are configured in Reg 08h[13:0]. All of the pins can configured to be either inputs or outputs by writing to
Reg 08h[13:9]. In frequency sweep mode, pin D4 can be used as an external trigger pin, by writing Reg 08h[13] = 0.

Writing to Reg 08h[3:0] selects DC - 7 GHz FRACTIONAL-N DIVIDER’s internal signals to be multiplexed out on the
GPIO pins, as shown in Table 5. Signals include:

1. The output of the Delta-Sigma Modulator Reg 08h[3:0] = ‘0010’b.

2. GPIO test signals Reg 08h[3:0] = ‘0000’b, which outputs data written to Reg 08h[8:4] to test the GPIO pins.
3. Sweep status flags, when the DC - 7 GHz FRACTIONAL-N DIVIDER is configured to be in sweep mode Reg
08h[3:0] = ‘1000’b.

Table 5. GPIO Pin Assignment and Output Signals

DC - 7 GHz FRACTIONAL-N DIVIDER GPIO Pins
Reg 08h[3:0]
D4 D3 D2 D1 D0
0000 gpo_test_out[4] gpo_test_out[3] gpo_test_out[2] gpo_test_out[1] gpo_test_out[0]

0001 reserved reserved reserved reserved reserved

0010 DSM_OUT[4] DSM_OUT[3] DSM_OUT[2] DSM_OUT[1] DSM_OUT[0]

0011 reserved reserved reserved reserved reserved

0100 reserved reserved reserved reserved reserved

0101 reserved reserved reserved reserved reserved

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of patents or other Elizabeth Drive, 01824
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 HMC983LP5E
v02.0112

DC - 7 GHz FRACTIONAL-N DIVIDER

AND FREQUENCY SWEEPER

Table 5. GPIO Pin Assignment and Output Signals

DC - 7 GHz FRACTIONAL-N DIVIDER GPIO Pins
Reg 08h[3:0]
D4 D3 D2 D1 D0

Frequency Dividers & Detectors - SMT

0110 reserved reserved reserved 0 0

0111 reserved reserved reserved reserved reserved

1000 ramp_ready_flag ramp_start_flag ramp_stop_flag ramp_busy_falg reserved

1001-1111 0 0 0 0 0

Fractional Mode of Operation

In addition to providing simple integer division ratios, the DC - 7 GHz FRACTIONAL-N DIVIDER has a sophisticated,
configurable 48-bit Delta Sigma Modulator (DSM), that allows fractional division of the input frequency in ultra fine
steps. The DSM’s size can be configured to 16/24/32/48 bits (Reg 16h[5:0]). DC - 7 GHz FRACTIONAL-N DIVIDER’s
auto-seed mode allows coherent frequency sweeps.
The DC - 7 GHz FRACTIONAL-N DIVIDER with its counterpart (the AND FREQUENCY SWEEPER), together with an
external VCO comprise a fully functional fractional-N synthesizer. In that case, the output frequency of the external
VCO is given by:

f f (Eq 1)
fvco = xtal ⋅ Nint + xtal L ⋅ Nfrac =fint + ffrac
R R⋅2

When the DC - 7 GHz FRACTIONAL-N DIVIDER is being used as frequency divider, the output frequency is given
by;

fvco
fout = (Eq 2)
N
Nint + frac
2L
Where
f vco is the VCO frequency in Hz;
fxtal is the crystal oscillator frequency in Hz;
Nint is the integer part of frequency division ratio (set in Reg 05h[19:0]);
Nfrac is the fractional part of frequency division ratio (Nfrac[47:18] = Reg 06h[29:0], Nfrac[17:0] = Reg 07h[17:0])
R is the reference frequency division ratio;
L is the size of the DSM accumulators (set in Reg 16h[5:0])

Example 1: Calculate the VCO frequency with the following parameters;

fxtal = 50 MHz; fpfd = 25 MHz
Nint = 25; Nfrac = 1; L = 24
Where fPFD is the frequency at the phase detector, thus R = 2. According to (Eq 1), the VCO frequency with the above
parameters will be;

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 HMC983LP5E
v02.0112

DC - 7 GHz FRACTIONAL-N DIVIDER

AND FREQUENCY SWEEPER

50MHz 50MHz
=
fvco⋅ 25 + = ⋅ 1 2500MHz + 1.49Hz
2 2 ⋅ 224
Frequency Dividers & Detectors - SMT

If accumulator width (L) is changed to 48-bit, then the frequency resolution will improve and the fractional resolution
of the VCO frequency will be 88.8178 nano-Hz.
Example 2: Set the VCO frequency to 4600.025 MHz using 100 MHz Crystal, R = 2 and L = 16. Compare if L = 32.
For this example the fPFD = 100 MHz/2 = 50 MHz,
The overall division ratio is 4600.025 MHz/50 MHz = 92.0005
The nearest integer would be 92, thus Nint = Reg 05h[19:0] = 92d = 5Ch.
For L = 16, Nfrac = 32.768 or 33d rounded up. Thus Nfrac = 33d or 21h (Reg 06h[29:0] = 0, Reg 07h[17:0] = 21h).
For L = 32, Nfrac = 2147483.648 or 2147484d rounded up. Thus Nfrac = 20C49Ch (Reg 06h[29:0] = 8h, Reg 07h[17:0]
= ‘001100010010011100‘d).
Since Nfrac must be an integer, the actual frequencies in the two cases will have an error of + 177.02 Hz for L = 16 and
only +0.004098 Hz for L = 32.

Phase Noise in Integer and Fractional Modes

In a normal integer frequency divider the in-band phase noise is scaled from the input phase noise by 20Log10(N),
where N is the divider value. In HMC983LP5E fractional mode, the frequency divider is modulated by the Delta Sigma
Modulator to generate output frequencies that are fractional multiple of the input frequency. Delta Sigma Modulator
shapes the quantization noise such that quantization noise density has a high pass shape which peaks at Fs/2,
where Fs is the sampling frequency (the divider output frequency in case of HMC983LP5E). In fractional mode this
quantization noise peak appears at an offset frequency of Fout/2. In the PLL, this peak is attenuated by the loop filter.
However, when the HMC983LP5E is used stand-alone in fractional mode its output will exhibit the quantization noise
as shown in Figure 2 and Figure 3. As a result, it is not possible to achieve the same noise floor in fractional mode as
in integer mode without further filtering.

CW Frequency Sweeper
The DC - 7 GHz FRACTIONAL-N DIVIDER features a built-in frequency sweeper function that supports automatic or
externally triggered sweeps. External triggering can be executed via an external trigger pin D4 or the SPI interface.
DC - 7 GHz FRACTIONAL-N DIVIDER sweep function can be configured to operate in the following modes:
• 2-Way sweep mode
• Repeating alternating positive and negative frequency sweep ramps
• Frequency increments swept with automatic sequencer
• Automatic or triggered
• Symmetric or asymmetric (the positive ramp can have a different slope from that of the negative ramp)
• 1-Way Sweep Mode
• Repeating one directional frequency sweeps followed by a reset to the starting frequency
• Frequency increments swept with automatic sequencer
• Triggered
User defined sweep mode
• Manually programmed user defined sweep patterns
• Triggered
• Symmetric or asymmetric (the positive ramp can have a different slope from that of the negative ramp)
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Phone: 978-250-3343 Fax: 978-250-3373 Phone: Order781-329-4700
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 HMC983LP5E
v02.0112

DC - 7 GHz FRACTIONAL-N DIVIDER

AND FREQUENCY SWEEPER

In all sweep modes, the starting sweep direction can be set to positive (increasing) or negative (decreasing). The
trigger can be applied instantaneously or delayed by a programmable time delay.
DC - 7 GHz FRACTIONAL-N DIVIDER’s sweep function is illustrated in Figure 24. The
DC - 7 GHz FRACTIONAL-N DIVIDER generates a frequency sweep by implementing automatic, or triggered in User

Frequency Dividers & Detectors - SMT

Defined Mode, discrete miniature frequency increments in time. A smooth and continuous sweep is then generated, at
the output of the VCO, after the stepped signal is filtered by the loop filter, as shown in Figure 24. The stepped sweep
approach enables the frequency synthesizer (comprising of DC - 7 GHz FRACTIONAL-N DIVIDER together with its
counterpart, the HMC984LP4E) to be in lock for the entire duration of the sweep. This approach results in a number
of advantages over conventional methods including:
• The ability to generate a linear sweep.
• The ability to have phase coherence between different sweep ramps, so that the phase profile of each sweep is
identical.
• The ability to generate user defined sweeps in User Defined Sweep Mode.

Figure 24. DC - 7 GHz FRACTIONAL-N DIVIDER Sweep Function

It is important to note that the synthesized ramp is subject to normal phase locked loop dynamics. If the loop bandwidth
in use is much wider than the rate of frequency increments then the locking will be fast and the ramp will have a
staircase shape. If the update rate is higher than the loop bandwidth, as is normally the case, the loop will not fully
settle before a new frequency step is received. Hence the swept output will have a lag and will sweep in a near
continuous fashion.
In all sweep modes, ramp_busy flag indicates an active sweep and will stay high between the 1st and nth ramp
increment. ramp_busy may be monitored on pin D1 by setting Reg 08h[3:0] = 8h.

Triggering
In sweep mode, the DC - 7 GHz FRACTIONAL-N DIVIDER can be triggered via one of two methods
• SPI trigger by setting Reg 0Eh[12]=1. This triggering method is asynchronous to the reference clock. To enable
SPI trigger write Reg 0Eh[13] = 0.
• or applying an external trigger on pin D4. Setting Reg 0Eh[13] = 1 and Reg 08h[13] = 0h configures
DC - 7 GHz FRACTIONAL-N DIVIDER’s pin D4 as external trigger input. External trigger on pin D4 is triggered
on the rising edge of the trigger. GPIO master enable (Reg 01h[4] = 1) is also required.

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Phone: 978-250-3343 Fax: 978-250-3373 Phone:
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 HMC983LP5E
v02.0112

DC - 7 GHz FRACTIONAL-N DIVIDER

AND FREQUENCY SWEEPER

• External triggering method can be synchronized with the reference clock, by enabling trigger delay (Reg
0Eh [7] = 1), and programming a trigger delay in Reg 05h[20:0] = number of delayed reference periods.
Writing Reg 05h[20:0] = 1 for example ensures that the trigger is applied at the instant of the rising edge of
the next reference rising edge. To disable trigger delay write Reg 0Eh [7] = 0.
Frequency Dividers & Detectors - SMT

2-Way Sweep Mode

DC - 7 GHz FRACTIONAL-N DIVIDER’s 2-Way sweep mode is shown in Figure 25. The 2-Way sweep mode can be
automatic or triggered. In automatic 2-way sweep, the trigger is generated internally based on user defined 2-way
sweep mode configuration. In a triggered 2-way sweep, frequency ramps are triggered either by external pin D4, or
SPI trigger.

Figure 25. DC - 7 GHz FRACTIONAL-N DIVIDER 2-Way Triggered Sweep

Triggered 1-Way Sweeps

DC - 7 GHz FRACTIONAL-N DIVIDER’s 1-Way sweeps is shown in Figure 26. Unlike 2-Way sweeps, 1-Way sweeps
require that the VCO hop back to the start frequency after the dwell period. Triggered 1-Way sweeps also require a
3rd trigger to start the new sweep. The 3rd trigger must be timed appropriately to allow the VCO to settle after the
large frequency hop back to the start frequency. Subsequent odd numbered triggers will start each sweep and repeat
the process.

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of patents or other Elizabeth Drive, 01824
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106
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Phone: 978-250-3343 Fax: 978-250-3373 Phone: Order781-329-4700
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 HMC983LP5E
v02.0112

DC - 7 GHz FRACTIONAL-N DIVIDER

AND FREQUENCY SWEEPER

Frequency Dividers & Detectors - SMT

Figure 26. DC - 7 GHz FRACTIONAL-N DIVIDER 1-Way Triggered Sweep
1-Way sweeps are not recommended in auto-sweep mode since in auto-sweep the new sweep will start immediately
after the 2nd trigger, as it does in 2-Way mode.

User Defined Sweep Mode

In User Defined Sweep mode, the DC - 7 GHz FRACTIONAL-N DIVIDER is able to generate various user-defined
sweep patterns by adjusting the time interval between adjacent frequency increments, which are executed by trigger
events. DC - 7 GHz FRACTIONAL-N DIVIDER’s User Defined Sweep Mode is shown in Figure 27. In this mode, an
external trigger is required for each frequency increment of the sweep.

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Phone: 978-250-3343 Fax: 978-250-3373 Phone:
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 HMC983LP5E
v02.0112

DC - 7 GHz FRACTIONAL-N DIVIDER

AND FREQUENCY SWEEPER
Frequency Dividers & Detectors - SMT

Figure 27. DC - 7 GHz FRACTIONAL-N DIVIDER User Defined Sweep

User defined sweep can function in both 1-Way or 2-Way sweep mode. In 1-Way sweep mode, the n+1 trigger will
cause the ramp to jump to the start frequency, and the n+2 trigger will restart the 1-way sweep.

Detailed Sweeper Configuration

Recommended procedure for configuring DC - 7 GHz FRACTIONAL-N DIVIDER sweeper in all three modes is shown
in Table 6.

Information furnished by Analog Devices is believed to be accurate and reliable. However, no

For price, delivery and to place orders: For price, 2delivery, and to placeChelmsford,
orders: Analog MA
Devices, Inc.,
responsibility is assumed by Analog Devices for its use, nor for anyHittite Microwave
infringements Corporation,
of patents or other Elizabeth Drive, 01824
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106
rights of third parties that may result from its use. Specifications subject to change without notice. No
Phone: 978-250-3343 Fax: 978-250-3373 Phone: Order781-329-4700
On-line at www.hittite.com
21 license is granted by implication or otherwise under any patent or patent rights of Analog Devices.
Application
• Order online at www.analog.com
Support: Phone: 1-800-ANALOG-D
Trademarks and registered trademarks are Application Support:
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 HMC983LP5E
v02.0112

DC - 7 GHz FRACTIONAL-N DIVIDER

AND FREQUENCY SWEEPER

Table 6. DC - 7 GHz FRACTIONAL-N DIVIDER Sweeper Configuration Sequence

Sweeper Modes
Steps Description
2-Way Sweep Mode User Defined Sweep Mode 1-Way Sweep Mode

Frequency Dividers & Detectors - SMT

Lock to start • set the integer (Reg 05h) and fractional (Reg 06h and Reg 07h) divider values.
1
frequency (fo) • Optionally, if required the seed (Reg 0Ah and Reg 0Bh) can also be programmed

Place the DSM

2 • Write Reg 0Eh[11] = 1
in sweep mode

• Disable single step ramp mode (Reg

• Enable the single step ramp mode
0Eh[24] = 0), so that each frequency • Disable single step ramp mode (Reg
(Reg 0Eh[24] = 1), so that each
increment will be incremented 0Eh[24] = 0), so that each frequency
frequency increment will require a
automatically increment will be incremented
trigger
• Enable 2-way sweep mode (Disable automatically
1-way sweep mode (Reg 0Eh[25] • Enable 1-way sweep mode (Reg
Configure • Enable 1-way sweep mode (Reg
3 = 0)) 0Eh[25] = 1), or enable 2-Way
sweep mode 0Eh[25] = 1)
• ToplacetheDC-7GHzFRACTIONAL-NDIVIDER sweep mode (Reg 0Eh[25] = 1)
in automatic sweep mode write • ToplacetheDC-7GHzFRACTIONAL-NDIVIDER
• ToplacetheDC-7GHzFRACTIONAL-NDIVIDER
Reg 0Eh[2:3] = ‘11’. To place the in triggered mode write Reg 0Eh[2:3]
in triggered mode write Reg 0Eh[2:3]
DC-7GHzFRACTIONAL-NDIVIDERin = ‘00’. Automatic 1-Way Sweep
= ‘00’. Automatic User Defined
triggered mode write Reg 0Eh[2:3] = mode is not supported.
Sweep mode is not supported.
‘00’.
Program
4 Sweep • Reg 0Eh[26] = 1 begin sweep in positive direction, Reg 0Eh[26] = 0 begin sweep in negative direction
Direction
• Program ramp mode (symmetrical - Reg 0Eh[22] = 1, asymmetrical - Reg
Configure 0Eh[22] = 0). If symmetrical ramp mode is selected (Reg 0Eh[22] = 1), only
• Program Reg 0Eh[22] = 1.
symmetrical/ Up sweep parameters will be used for both positive and negative sweeps,
5 Asymmetrical sweep is not defined
asymmetrical and hence down sweep parameters don’t need to be programmed. In
in 1-Way Sweep mode
sweep symmetrical ramp mode the positive and negative ramps are identical and
opposite in direction.
Program • Set dwell time(dwell time[47:0] = Reg 10h[29:0], dwell time[17:0] = Reg 11h[17:0])
6 Up Sweep • Set step size (step size[47:18] = Reg 12h[29:0], step size[17:0] = Reg 13h[17:0])
Parameters • Set the number of steps in a sweep (number of steps[47:18] = Reg 14h[29:0], number of steps[17:0] = Reg 15h[17:0])
Program
Down Sweep • Set dwell time (dwell time[47:0] = Reg 06h[47:18], dwell time[17:0] = Reg
Parameters 07h[17:0])
(Only if using • Set step size (step size[47:18] = Reg 19h[29:0], step size[17:0] = Reg • Asymmetrical sweep is not defined
7
asymmetrical 1Ah[17:0]) in 1-Way Sweep mode
sweep (if Reg • Set the number of steps in a sweep (number of steps[47:18] = Reg 0Ch[29:0],
0Eh[22] = 0) in number of steps[17:0] = Reg 0Dh[17:0])
Step 5)
• To use SPI trigger write Reg 0Eh[13] = 0 to select SPI trigger. SPI trigger is executed by writing to Reg 0Eh[12] = 1.
• To use external trigger on pin D4 write Reg 0Eh[13] = 1 to configure pin D4 as an external trigger. Write Reg 08h[13]
= 0h to configure pin D4 to be an input. Applying master enable to GPIO pins (Reg 01h[4] = 1 ) is required.
Configure and
8 • Enable trigger delay (Reg 0Eh[7] = 1), or disable trigger delay (Reg 0Eh[7] = 0).
apply trigger
• If using trigger delay, write delay value to Reg 05h[20:0], where Reg 05h[20:0] = number of delayed reference
periods. Writing Reg 05h[20:0] = 1 for example ensures that the trigger is applied at the instant of the rising edge
of the next reference rising edge.

DC - 7 GHz FRACTIONAL-N DIVIDER sweep parameters are defined in the following way:
fo Initial frequency of the synthesizer
ff Frequency of the synthesizer at the end of the sweep
R Reference divider value(Reg 02h[13:0])

Information furnished by Analog Devices is believed to be accurate and reliable. However, no

For price, delivery and to place orders: For price, 2delivery, and to placeChelmsford,
orders: Analog MA
Devices, Inc.,
responsibility is assumed by Analog Devices for its use, nor for anyHittite Microwave
infringements Corporation,
of patents or other Elizabeth Drive, 01824
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106
rights of third parties that may result from its use. Specifications subject to change without notice. No
Phone: 978-250-3343 Fax: 978-250-3373 Phone:
license is granted by implication or otherwise under any patent or patent rights of Analog Devices.
Order781-329-4700
On-line at www.hittite.com
• Order online at www.analog.com 22
Trademarks and registered trademarks are Application Support:
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 HMC983LP5E
v02.0112

DC - 7 GHz FRACTIONAL-N DIVIDER

AND FREQUENCY SWEEPER

stepsize frequency increment step size. In case of symmetric and UP sweeps, stepsize[47:18] =
Reg 12h[29:0], stepsize[17:0] = Reg 13h[17:0]). In case of asymmetric sweeps,
(downsweep stepsize[47:18] = Reg 12h[29:0], down sweep stepsize[17:0] = Reg 13h[17:0])
Frequency Dividers & Detectors - SMT

fxtal
∆fstep Frequency step size = stepsize ⋅ ,
2L ⋅ R
L Size of the DSM (set in Reg 16h[5:0])
R
Tref Period of the divided reference (fPFD) at the phase detector. Tref =
fxtal

N Total number of frequency step increments in a single sweep. N [47:18] = Reg 14h[29:0],
N[17:0] = Reg 15h[17:0]
Tramp Total time of one frequency sweep from fo to ff. Tramp = Tref x N
Then final frequency ff is given by: ff = fo + (∆fstep x N)
Setting autoseed (Reg 0Eh[8] = 1) ensures that different sweeps have identical phase profile. This is achieved
by loading the seed (seed[47:18] = Reg 0Ah[29:0], seed[17:0] = Reg 0Bh[17:0]) into the phase accumulator at the
beginning of each ramp.
Example: Calculate sweep parameters for an asymmetric 2-Way sweep from f0 = 3000 MHz to ff = 3105 MHz with
positive Tramp ≈ 2 ms, and negative Tramp ≈ 4 ms, and positive dwell time = negative dwell time = 2 µs, with fPD = 50
MHz, and a 48-bit delta-sigma modulator size. Assuming R = 1.
1. Calculate the integer and fractional divider values for initial start frequency f0
• Start Nint = Reg 05h = 60d
• Start Nfrac = Reg 06h = Reg 07h = 0d
2. Calculate the number of divided (R = 1) reference periods in the sweep = number of frequency increments N
• Nup = 2 ms/(1/50 MHz) = 100000
• Ndown = 4 ms/(1/50 MHz) = 200000
3. Calculate stepsize (size of frequency increments)
• stepssize up = abs(ff - f0)/Nup = abs(3000 MHz - 3105 MHz)/100000 = 1050 Hz. Then as per Table 6, Reg
12h[29:0] = 0h, Reg 13h[17:0] = 1050d = 41Ah
• stepsize down = abs(ff - f0)/Ndown = abs(3000 MHz - 3105 MHz)/200000 = 525 Hz Then as per Table 6,
Reg 19h[29:0] = 0h, Reg 1Ah[17:0] = 1050d = 41Ah
Note that it is possible to have a case where the frequency ff cannot be generated exactly. In that case it is
required to approximate the final frequency to ff = fo + (∆fstep x N) ≈ desired final frequency.
4. Calculate number of divided (R = 1) reference periods in required dwell time
• Up dwell time (Reg 10h[29:0], Reg 11h[17:0]) = down dwell time (Reg 06h[29:0], Reg 07h[17:0]) = dwell
time/ (1/ 50 MHz) = 2 µs/(1/50 MHz) = 100. Then as per Table 6, Reg 10h[29:0] = Reg 06h[29:0] = 0h, and
Reg 11h[17:0] = Reg 07h[17:0] = 100d = 64h.
Then proceed to configure the sweep according to the steps outlined in Table 6.

Serial Port Interface

The DC - 7 GHz FRACTIONAL-N DIVIDER features a four wire serial port for simple communication with the host
controller. Typical serial port operation can be run with SCK at speeds up to 30 MHz.
The details of SPI access for the DC - 7 GHz FRACTIONAL-N DIVIDER is provided in the following sections. Note that
the READ operation below is always preceded by a WRITE operation to Register 0 to define the register to be queried.
Also note that every READ cycle is also a WRITE cycle in that data sent to the SPI while reading the data will also be
stored by the DC - 7 GHz FRACTIONAL-N DIVIDER when SENb goes high. If this is not desired then it is suggested
to write to Register 0 during the READ operation so that the status of the device will be unaffected.
Information furnished by Analog Devices is believed to be accurate and reliable. However, no
For price, delivery and to place orders: For price, 2delivery, and to placeChelmsford,
orders: Analog MA
Devices, Inc.,
responsibility is assumed by Analog Devices for its use, nor for anyHittite Microwave
infringements Corporation,
of patents or other Elizabeth Drive, 01824
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106
rights of third parties that may result from its use. Specifications subject to change without notice. No
Phone: 978-250-3343 Fax: 978-250-3373 Phone: Order781-329-4700
On-line at www.hittite.com
23 license is granted by implication or otherwise under any patent or patent rights of Analog Devices.
Application
• Order online at www.analog.com
Support: Phone: 1-800-ANALOG-D
Trademarks and registered trademarks are Application Support:
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 HMC983LP5E
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DC - 7 GHz FRACTIONAL-N DIVIDER

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Power on Reset and Soft Reset

The DC - 7 GHz FRACTIONAL-N DIVIDER has a built in Power On Reset (POR) and a serial port accessible Soft
Reset (SR). POR is accomplished when power is cycled for the DC - 7 GHz FRACTIONAL-N DIVIDER while SR is

Frequency Dividers & Detectors - SMT

accomplished via the SPI by writing Reg 00h = 80h, followed by writing Reg 00h =00h. All chip registers will be reset
to default states approximately 250 us after power up.

Serial Port WRITE Operation

The host changes the data on the falling edge of SCK and the DC - 7 GHz FRACTIONAL-N DIVIDER reads the data
on the rising edge.
A typical WRITE cycle is shown in Figure 28. It is 40 clock cycles long.
1. The host both asserts SENb (active low Serial Port Enable) and places the MSB of the data on SDI followed
by a rising edge on SCK.
2. DC - 7 GHz FRACTIONAL-N DIVIDER reads SDI (the MSB) on the 1st rising edge of SCK after SENb.
3. DC - 7 GHz FRACTIONAL-N DIVIDER registers the data bits, D29:D0, in the next 29 rising edges of SCK
(total of 30 data bits).
4. Host places the 5 register address bits, A6:A0, on the next 7 falling edges of SCK (MSB to LSB) while the
DC - 7 GHz FRACTIONAL-N DIVIDER reads the address bits on the corresponding rising edge of SCK.
5. Host places the 3 chip address bits, CA2:CA0=[110], on the next 3 falling edges of SCK (MSB to LSB). Note
the DC - 7 GHz FRACTIONAL-N DIVIDER chip address is fixed as “7d” or “111b”.
6. SENb goes from low to high after the 40th rising edge of SCK. This completes the WRITE cycle.
7. DC - 7 GHz FRACTIONAL-N DIVIDER also exports data back on the SDO line. For details see the section
on READ operation.

Serial Port READ Operation

The SPI can read from the internal registers in the chip. The data is available on SDO pin. This pin itself is tri-stated
when the device is not being addressed. However when the device is active and has been addressed by the SPI
master, the DC - 7 GHz FRACTIONAL-N DIVIDER controls the SDO pin and exports data on this pin during the next
SPI cycle.
DC - 7 GHz FRACTIONAL-N DIVIDER changes the data to the host on the rising edge of SCK and the host reads the
data from DC - 7 GHz FRACTIONAL-N DIVIDER on the falling edge.
A typical READ cycle is shown in Figure 28. Read cycle is 40 clock cycles long. To specifically read a register, the
address of that register must be written to dedicated Reg 0h. This requires two full cycles, one to write the
required address, and a 2nd to retrieve the data. A read cycle can then be initiated as follows;
1. The host asserts SENb (active low Serial Port Enable) followed by a rising edge SCK.
2. DC - 7 GHz FRACTIONAL-N DIVIDER reads SDI (the MSB) on the 1st rising edge of SCK after SENb.
3. DC - 7 GHz FRACTIONAL-N DIVIDER registers the data bits in the next 29 rising edges of SCK (total of 30
data bits). The LSBs of the data bits represent the address of the register that is intended to be read.
4. Host places the 7 register address bits on the next7 falling edges of SCK (MSB to LSB) while the
DC - 7 GHz FRACTIONAL-N DIVIDER reads the address bits on the corresponding rising edge of SCK. For
a read operation this is “0000000”.
5. Host places the 3 chip address bits [111] on the next 3 falling edges of SCK (MSB to LSB).
6. SENb goes from low to high after the 40th rising edge of SCK. This completes the first portion of the READ
cycle.
7. The host asserts SENb (active low Serial Port Enable) followed by a rising edge SCK.

Information furnished by Analog Devices is believed to be accurate and reliable. However, no

For price, delivery and to place orders: For price, 2delivery, and to placeChelmsford,
orders: Analog MA
Devices, Inc.,
responsibility is assumed by Analog Devices for its use, nor for anyHittite Microwave
infringements Corporation,
of patents or other Elizabeth Drive, 01824
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106
rights of third parties that may result from its use. Specifications subject to change without notice. No
Phone: 978-250-3343 Fax: 978-250-3373 Phone:
license is granted by implication or otherwise under any patent or patent rights of Analog Devices.
Order781-329-4700
On-line at www.hittite.com
• Order online at www.analog.com 24
Trademarks and registered trademarks are Application Support:
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 HMC983LP5E
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DC - 7 GHz FRACTIONAL-N DIVIDER

AND FREQUENCY SWEEPER

8. DC - 7 GHz FRACTIONAL-N DIVIDER places the 30 data bits, 7 address bits, and 3 chip id bits, on the SDO,
on each rising edge of the SCK, commencing with the first rising edge beginning with MSB.
9. The host de-asserts SENb (i.e. sets SENb high) after reading the 40 bits from the SDO output. The 40 bits
Frequency Dividers & Detectors - SMT

consists of 30 data bits, 7 address bits, and the 3 chip id bits. This completes the read cycle.
Note that the data sent to the DC - 7 GHz FRACTIONAL-N DIVIDER SPI during this portion of the READ
operation is stored in the SPI when SENb is de-asserted. It is recommended that during the second phase
of the READ operation that Reg 00h is addressed with either the same address or the address of another
register to be read during the next cycle.

Figure 28. SPI Timing Diagram

DVDD = 5 V ±10%, GND = 0 V

Table 7. Main SPI Timing Characteristics

Parameter Conditions Min Typ Max Units

t1 SDI to SCK Setup Time 8 nsec

t2 SDI to SCK Hold Time 8 nsec

t3 SCK High Duration [1] 10 nsec

t4 SCK Low Duration 10 nsec

t5 SENb Low Duration 20 nsec

t6 SENb High Duration 20 nsec

t7 SCK to SENb [2] 8 nsec

t8 SCK to SDO out [3] 8 nsec

[1] The SPI is relatively insensitive to the duty cycle of SCK.

[2] SENb must rise after the 32nd falling edge of SCK but before the next rising SCK edge. If SCK is shared amongst several devices this timing
must be respected.
[3] Typical load to SDO is 10 pF, maximum 20 pF

Information furnished by Analog Devices is believed to be accurate and reliable. However, no

For price, delivery and to place orders: For price, 2delivery, and to placeChelmsford,
orders: Analog MA
Devices, Inc.,
responsibility is assumed by Analog Devices for its use, nor for anyHittite Microwave
infringements Corporation,
of patents or other Elizabeth Drive, 01824
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106
rights of third parties that may result from its use. Specifications subject to change without notice. No
Phone: 978-250-3343 Fax: 978-250-3373 Phone: Order781-329-4700
On-line at www.hittite.com
25 license is granted by implication or otherwise under any patent or patent rights of Analog Devices.
Application
• Order online at www.analog.com
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 HMC983LP5E
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DC - 7 GHz FRACTIONAL-N DIVIDER

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Register Map

Table 8. Reg 00h Chip ID, Soft Reset, Read Register

Frequency Dividers & Detectors - SMT

BIT TYPE NAME W DEFLT DESCRIPTION

[6:0] R/W Read Register Address 7 0 Address of the register to be read in the next cycle.

Soft Reset. Writing 1 generates soft reset. Resets all the digital and
[7] R/W Soft Reset 1 0
registers to default states. Writing 0 resumes normal chip operation.

[31:8] R/W Chip ID 24 97330h Part Number, Description. Read reg00h returns chip ID.

Table 9. Reg 01h - Settings Register

BIT TYPE NAME W DEFLT DESCRIPTION

[0] R/W VCO Buffer Enable 1 1 Enables VCO input RF buffer.

[1] R/W Reserved 1 1 Write 0 to this bit.

[2] R/W AUXSPI Enable 1 1 Enables Auxiliary SPI.

[3] R/W Sigma Delta Enable 1 1 Enables Sigma Delta Function.

[4] R/W GPIO Enable 1 1 Enables output from all GPIO pins.

[5] R/W RF Divider Enable 1 1 Enables RF Divider.

[6] R/W Output Buffer Enable 1 1 Enables Divider Output Driver.

[7] R/W Bias Enable 1 1 Enables bias generator for all blocks.

[8] R/W PSCLK to Digital Enable 1 1 Enable Prescaler clock going to digital counters.

[9] R/W Unused 1 1

Table 10. Reg 02h R-Divider Register

BIT TYPE NAME W DEFLT DESCRIPTION

[13:0] R/W R Divider Ratio 14 1h Local value for reference division ratio.

Auxiliary SPI Registers

The following two registers define the communication through the AUXSPI. If the AUXSPI is enabled (Reg 04h[4]
= 0), writes to AUXSPI are executed via Reg 03h. The auxiliary device address is expected in Reg 04h[2:0]. If
DC - 7 GHz FRACTIONAL-N DIVIDER is working as a standalone frequency divider the AUXSPI clock is expected on
the DNSAT pin, and Reg 04h[15] must be set to 1. It is recommended to disable AUXSPI when not used.

Table 11. Reg 03h AUX. VCO Data Register

BIT TYPE NAME W DEFLT DESCRIPTION

[3:0] R/W AUXSPI Register Address 4 0h 4-bit Register address for the auxiliary device SPI.

[12:4] R/W AUXSPI Data 9 000h 9-bit long Register Data for the auxiliary device SPI.

Information furnished by Analog Devices is believed to be accurate and reliable. However, no

For price, delivery and to place orders: For price, 2delivery, and to placeChelmsford,
orders: Analog MA
Devices, Inc.,
responsibility is assumed by Analog Devices for its use, nor for anyHittite Microwave
infringements Corporation,
of patents or other Elizabeth Drive, 01824
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106
rights of third parties that may result from its use. Specifications subject to change without notice. No
Phone: 978-250-3343 Fax: 978-250-3373 Phone:
license is granted by implication or otherwise under any patent or patent rights of Analog Devices.
Order781-329-4700
On-line at www.hittite.com
• Order online at www.analog.com 26
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 HMC983LP5E
v02.0112

DC - 7 GHz FRACTIONAL-N DIVIDER

AND FREQUENCY SWEEPER

Table 12. Reg 04h - AUX. VCO Settings Register

BIT TYPE NAME W DEFLT DESCRIPTION
Frequency Dividers & Detectors - SMT

[2:0] R/W Auxiliary Device Address 3 000h Chip address used by AUXSPI.

0 = Use XTAL for AUXSPI clock.

[3] R/W Divide Clock by 4 for AUXSPI 1 0
1 = Use XTAL divided by 4 for AUXSPI clock.

0 = Start AUXSPI when data is written to Reg03h.

[4] R/W Start AUXSPI 1 0
1 = reserved.

[7:5] R/W Reserved 3 4h

[9:8] R/W Reserved 2 2h

[13:10] R/W Reserved 4 8h

[14] R/W Reserved 1 0

When 1, keeps the XTAL gate open to get XTAL from the
[15] R/W Keep Xtal Gate Open 1 0
companion PFD/CP chip HMC984LP4E.

[18:16] R/W Reserved 3 0h

Table 13. Reg 05h Integer Set-Point, Trigger Delay Register

BIT TYPE NAME W DEFLT DESCRIPTION

Sigma-Delta Modulator integer set point. Specifies the integer

Integer Division Ratio part of the division ratio for the RF Divider in fractional mode or
[19:0] R/W 20 200d the integer division ration in integer mode.

Also used as delay counter for hardware ramp trigger (Pin D4) in
Ramp Trigger Delay
ramp mode. This value is valid when Reg 0Eh [11] = 1.

Table 14. Reg 06h Fractional Set-Point, Down Dwell Register (MSB)
BIT TYPE NAME W DEFLT DESCRIPTION

Most significant 30 bits to specify fractional set point for Sigma-

Fractional Division Ratio (MSB)
Delta Modulator. Total Fractional bits are 48.
[29:0] R/W 30 0
Down Dwell for Asymmetric Defines the MSB portion of the dwell down time in the
Frequency. Ramp (MSB) asymmetric frequency sweep mode, valid when Reg 0Eh[11]=1.

Table 15. Reg 07h Fractional Set-Point, Down Dwell Register (LSB)
BIT TYPE NAME W DEFLT DESCRIPTION

Least significant 18 bits to specify fractional set point for Sigma-

Fractional Division Ratio (LSB)
Delta Modulator. Total Fractional bit are 48.
[17:0] R/W 18 0
Down Dwell for Asymmetric Defines the LSB portion of the dwell down time in the asymmetric
Frequency. Ramp (LSB) frequency sweep mode, valid when Reg0E[11]=1.

Information furnished by Analog Devices is believed to be accurate and reliable. However, no

For price, delivery and to place orders: For price, 2delivery, and to placeChelmsford,
orders: Analog MA
Devices, Inc.,
responsibility is assumed by Analog Devices for its use, nor for anyHittite Microwave
infringements Corporation,
of patents or other Elizabeth Drive, 01824
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106
rights of third parties that may result from its use. Specifications subject to change without notice. No
Phone: 978-250-3343 Fax: 978-250-3373 Phone: Order781-329-4700
On-line at www.hittite.com
27 license is granted by implication or otherwise under any patent or patent rights of Analog Devices.
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 HMC983LP5E
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DC - 7 GHz FRACTIONAL-N DIVIDER

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Table 16. Reg 08h GPIO Configuration Register

BIT TYPE NAME W DEFLT DESCRIPTION

Frequency Dividers & Detectors - SMT

Selects exported output signals to GPIO pins. See Table 5 for
[3:0] R/W GPO Output Select 4 0h
details. Master enable for GPIO Reg 01h[4] = 1 is required..

Static GPIO test signals for output (D4,D3,D2,D1,D0). Writing

[8:4] R/W GPO Static Test Value 5 00000b these value and reading them back test the GPIO functionality.
Master enable for GPIO Reg 01h[4] = 1 is required..

Independent GPIO pin enables.

Reg08[13] = 0 - D4 input
Reg08[13] = 1 - D4 output
Reg08[12] = 0, D3 input
Reg08[12] =1, D3 output
Reg08[11] = 0, D2 input
[13:9] R/W GPO Pin Enable 5 11111b
Reg08[11] = 1, D2 output
Reg08[10] = 0, D1 input
Reg08[10] = 1, D1 output
Reg08[9] = 0, D0 input
Reg08[9] = 1, D0 output
Master enable for GPIO Reg 01h[4] = 1 is required.

Table 17. Reg 09h Companion Chip Address Local Register

BIT TYPE NAME W DEFLT DESCRIPTION

Counterpart HMC984LP4E Chip

[2:0] R/W 3 2h Chip address of the companion chip HMC984LP4E.
Address

Table 18. Reg 0Ah Sigma Delta Modulator Seed MSB Register
BIT TYPE NAME W DEFLT DESCRIPTION

Most significant bits of the Seed for the 1st accumulator in

[29:0] R/W Seed MSB 30 4241h
Sigma-Delta Modulator.

Table 19. Reg 0Bh Sigma Delta Modulator Seed LSB Register
BIT TYPE NAME W DEFLT DESCRIPTION

Least significant bits of the Seed for the 1st accumulator in

[17:0] R/W Seed LSB 18 10081h
Sigma-Delta Modulator.

Table 20. Reg 0Ch Ramp NSTEP Down MSB Register

BIT TYPE NAME W DEFLT DESCRIPTION

Down Ramp Number of Steps Most significant bits of the number of steps for the frequency
[29:0] R/W 30 0h
(MSB) ramp in down direction in sweep mode.

Table 21. Reg 0Dh Ramp NSTEP Down LSB Register

BIT TYPE NAME W DEFLT DESCRIPTION

Down Ramp Number of Steps Least significant bits of the number of steps for the frequency
[17:0] R/W 18 0h
(LSB) ramp in down direction in sweep mode.

Information furnished by Analog Devices is believed to be accurate and reliable. However, no

For price, delivery and to place orders: For price, 2delivery, and to placeChelmsford,
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Order781-329-4700
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 HMC983LP5E
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DC - 7 GHz FRACTIONAL-N DIVIDER

AND FREQUENCY SWEEPER

Table 22. Reg 0Eh Sigma Delta Modulator Configuration Register

BIT TYPE NAME W DEFLT DESCRIPTION
Frequency Dividers & Detectors - SMT

DSM Type.
00 = MASH1 - Reserved
[1:0] R/W SD Modulator Type 2 11b 01 = MASH11 - Reserved
10 = MASH111 - Delta Sigma Modulator Mode B
11 - Delta Sigma Modulator Mode A

Recommended to write 1 to this bit in ramp mode. When this bit

Ramp Auto Repeat Control from
[2] R/W 1 0 is 1, the ramp will repeat itself if ramp_auto_repeat_on/off_from_
SPI
spi is 1 at the end of the each sweep.

Ramp Auto Repeat Control from Ramp will automatically repeat itself if this bit is 1 and bit 2 is
[3] R/W 1 0
SPI On/Off also set to 1.

Delay through the integer signal path to compensate for the

fractional path.
[6:4] R/W Integer Path Delay 3 111 000 = no delay.
110 = 6 clock cycles delay.
111 = Automatic.

[7] R/W Ramp Start Delay Enable 1 0 Delay the start of sweep as defined in Reg 05h

[8] R/W Autoseed Mode Enable 1 1 Reseed when changing the frac setpoint.

1 = Enable Phase Step feature. Autoseed Mode must be

disabled for Phase Step (Reg 0Eh [8] = 0. Seed Reg Ah &
Reg Bh set the phase advance/retard in 2’s complement
[9] R/W Phase Step 1 0
formate. Phase Step takes effect when Reg 0Ah is written.
Each time registers are written phase will advance/retard by the
amount specified.

[10] R/W Maintain DSM State Enable 1 0 Maintain DSM state within the same integer boundary.

[11] R/W Ramp Mode Enable 1 0 Puts DSM in frequency sweeper (ramp) mode.

[12] R/W Ramp Start from SPI 1 0 Start ramp signal from SPI.

[13] R/W Start Ramp from Ext. Trigger 1 0 Allow external trigger to manipulate ramp.

Bypass Delta Sigma Modulator. Place synthesizer in Integer

[14] R/W Bypass All 1 0
Mode without disabling the DSM.

Cycle Slip Prevention (CSP) step size. In a PLL configuration

[18:15] R/W CSP Step Size 4 1111b with the HMC984LP4E one step is equivalent to one divided
VCO cycle, and step size is the number of VCO cycles.

[19] R/W External DSM Sequence Enable 1 0 Use external DSM sequence imported through GPIO Port.

Use Falling Edge of DSM Clock

[20] R/W 1 0 Use falling edge of SD clock to get the external sequence.
for External Sequence

Allow external trigger to start locking process. Writing to the

Integer or Fractional Division ratio registers does not have any
[21] R/W Lock using External Trigger Pin 1 0
effect when this bit is set to 1. PLL will lock only when external
trigger goes high.
Use symmetric frequency sweeping for up and down directions
[22] R/W Symmetrical Ramp Mode 1 1 otherwise DN parameters are taken from Registers Reg 0Ch,
Reg 0Dh, Reg 19h and Reg 1Ah for asymmetric mode.

[23] R/W Integer Mode Lock Strobe 1 0 Re-lock when integer set-point Reg 06h is updated.

Single-step the ramp. Each step of the ramp must be popped by

[24] R/W Singlestep Ramp Mode Enable 1 0
strobe (either SPI or Hardware pin).

Single Direction Ramp Mode Single direction mode for ramp (ramp one way, pop to base the
[25] R/W 1 0
Enable other way).

Starting direction of ramp. It is only loaded while rampmode = 0.

[26] R/W Ramp Start Direction 1 1 1 = Positive
0 = Negative

Information furnished by Analog Devices is believed to be accurate and reliable. However, no

For price, delivery and to place orders: For price, 2delivery, and to placeChelmsford,
orders: Analog MA
Devices, Inc.,
responsibility is assumed by Analog Devices for its use, nor for anyHittite Microwave
infringements Corporation,
of patents or other Elizabeth Drive, 01824
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106
rights of third parties that may result from its use. Specifications subject to change without notice. No
Phone: 978-250-3343 Fax: 978-250-3373 Phone: Order781-329-4700
On-line at www.hittite.com
29 license is granted by implication or otherwise under any patent or patent rights of Analog Devices.
Application
• Order online at www.analog.com
Support: Phone: 1-800-ANALOG-D
Trademarks and registered trademarks are Application Support:
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 HMC983LP5E
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DC - 7 GHz FRACTIONAL-N DIVIDER

AND FREQUENCY SWEEPER

[27] R/W Use External Clock for DSM 1 0 1 = Use external clock from GPIO pin to clock DSM.

[28] R/W Reserved 1 0

1 = Increase the CSP step size given in bits [18:15] by a factor

Frequency Dividers & Detectors - SMT

[29] R/W Use x16 CSP Step 1 0
of 16.

Table 23. Reg 0Fh VCO Divider Configuration Register

BIT TYPE NAME W DEFLT DESCRIPTION

Increase Divider Pulse width Increase the width of the clock pulse going to DSM (available
[0] R/W 1 0
to DSM only when division ratio > 64).

Increase Divider Pulsewidth to

[1] R/W 1 1 Increase pulse width (low duration) of the clock going to PFD.
PFD

Sets current for divider output buffer. Helps to control voltage

swing for various impedance options.
000 = 5mA
001 = 7.5mA
010 = 10mA
[4:2] R/W Output Buffer Current Select 2 011b
011 = 12.5mA
100 = 10mA
101 = 12.5mA
110 = 15mA
111 = 17.5mA

[5] R/W Reset RF Divider 1 0 Resets the RF Divider.

Bias current setting for divider resync. Default value

[8:6] R/W Divider Resynch Bias Select 3 011b
recommended.

Bias current setting for input RF buffer. Default value

[11:9] R/W RF Buffer Bias Select 3 001b
recommended.

Divider output pulse width control.

000 = 5 VCO cycles.
001 = 13 VCO cycles.
010 = 21 VCO cycles.
[14:12] R/W Divider Pulsewidth Select 3 011b 011 = 29 VCO cycles.
100 = 37 VCO cycles.
101 = 45 VCO cycles.
110 = 53 VCO cycles.
111 = 61 VCO cycles.

Table 24. Reg 10h Ramp DWELL Symmetrical or Up MSB Register

BIT TYPE NAME W DEFLT DESCRIPTION

Represents MSB’s for ramp dwell time in up and down directions

[29:0] R/W Symmetric Ramp Dwell (MSB) 30 0 for symmetric frequency sweep mode. In asymmetric mode it
represents the up dwell time only.

Table 25. Reg 11h Ramp DWELL Symmetrical or Up LSB Register

BIT TYPE NAME W DEFLT DESCRIPTION

Represents LSB’s for ramp dwell time in up and down directions

[17:0] R/W Symmetric Ramp Dwell (LSB) 18 0 for symmetric frequency sweep mode. In asymmetric mode it
represents the up dwell time only.

Information furnished by Analog Devices is believed to be accurate and reliable. However, no

For price, delivery and to place orders: For price, 2delivery, and to placeChelmsford,
orders: Analog MA
Devices, Inc.,
responsibility is assumed by Analog Devices for its use, nor for anyHittite Microwave
infringements Corporation,
of patents or other Elizabeth Drive, 01824
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106
rights of third parties that may result from its use. Specifications subject to change without notice. No
Phone: 978-250-3343 Fax: 978-250-3373 Phone:
license is granted by implication or otherwise under any patent or patent rights of Analog Devices.
Order781-329-4700
On-line at www.hittite.com
• Order online at www.analog.com 30
Trademarks and registered trademarks are Application Support:
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respective owners. Application Support: Phone: 1-800-ANALOG-D
or apps@hittite.com
 HMC983LP5E
v02.0112

DC - 7 GHz FRACTIONAL-N DIVIDER

AND FREQUENCY SWEEPER

Table 26. Reg 12h Ramp Step Size Symmetrical or Up MSB Register
BIT TYPE NAME W DEFLT DESCRIPTION
Frequency Dividers & Detectors - SMT

Represents the MSB for ramp step size in up and down

Symmetric Ramp Step Size
[29:0] R/W 30 0 directions for symmetric frequency sweep mode. In asymmetric
(MSB)
mode it represents the up step size only.

Table 27. Reg 13h Ramp Step Size Symmetrical or Up LSB Register
BIT TYPE NAME W DEFLT DESCRIPTION

Represents the LSB for ramp step size in up and down directions
Symmetric Ramp Step Size
[17:0] R/W 18 0 for symmetric frequency sweep mode. In asymmetric mode it
(LSB)
represents the up step size only.

Table 28. Reg 14h Ramp NSTEP Symmetrical or Up MSB Register

BIT TYPE NAME W DEFLT DESCRIPTION

Represents the MSB of the number of steps for the frequency

Symmetric Ramp Number of ramp in up and down directions in symmetric frequency sweep
[29:0] R/W 30 0
Steps (MSB) mode. In asymmetric mode it represents the number of steps in
up direction only.

Table 29. Reg 15h Ramp NSTEP Symmetrical or Up LSB Register

BIT TYPE NAME W DEFLT DESCRIPTION

Represents the LSB of the number of steps for the frequency

Symmetric Ramp Number of ramp in up and down directions in symmetric frequency sweep
[17:0] R/W 18 0
Steps (LSB) mode. In asymmetric mode it represents the number of steps in
up direction only.

Information furnished by Analog Devices is believed to be accurate and reliable. However, no

For price, delivery and to place orders: For price, 2delivery, and to placeChelmsford,
orders: Analog MA
Devices, Inc.,
responsibility is assumed by Analog Devices for its use, nor for anyHittite Microwave
infringements Corporation,
of patents or other Elizabeth Drive, 01824
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106
rights of third parties that may result from its use. Specifications subject to change without notice. No
Phone: 978-250-3343 Fax: 978-250-3373 Phone: Order781-329-4700
On-line at www.hittite.com
31 license is granted by implication or otherwise under any patent or patent rights of Analog Devices.
Application
• Order online at www.analog.com
Support: Phone: 1-800-ANALOG-D
Trademarks and registered trademarks are Application Support:
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respective owners. or apps@hittite.com
 HMC983LP5E
v02.0112

DC - 7 GHz FRACTIONAL-N DIVIDER

AND FREQUENCY SWEEPER

Table 30. Reg 16h DSM Configuration Register

BIT TYPE NAME W DEFLT DESCRIPTION

Frequency Dividers & Detectors - SMT

DSM 1st accumulator width.
00 = 48 bits
[1:0] R/W DSM 1st Accumulator Size 2 00b 01 = 32 bits
10 = 24 bits
11 = 16 bits

DSM 2nd accumulator width.

00 = 48 bits
[3:2] R/W DSM 2nd Accumulator Size 2 00b 01 = 32 bits
10 = 24 bits
11 = 16 bits

DSM 3rd accumulator width.

00 = 48 bits
[5:4] R/W DSM 3rd Accumulator Size 2 00b 01 = 32 bits
10 = 24 bits
11 = 16 bits

Clock gates for the 3 accumulators (fractional part), 1 disables

[8:6] R/W Disable Frac. Register Clock 3 000b
the clock.

Clock gates for the 3 accumulators (integer part), 1 disables the

[11:9] R/W Disable Integer Register Clock 3 000b
clock.

[12] R/W Disable DSM Mode A Clock 1 0 1 = Disable Delta Sigma Modulator Mode A Clock

[13] R/W Disable DSM Mode B Clock 1 0 1 = Disable Delta Sigma Modulator Mode B Clock

[14] R/W Reserved 1 0

[15] R/W Disable Integer Path Clock 1 0 1 = Disables Integer Path Clock

[16] R/W Disable Input Buffer Clock 1 0 1 = Disables Input Buffer Clock

[17] R/W Disable Output Buffer Clock 1 0 1 = Disables Output Buffer Clock

[18] R/W Reserved 1 0

[19] R/W Reserved 1 0

Table 31. Reg 17h This Register does not exist

BIT TYPE NAME W DEFLT DESCRIPTION

This Register does not exist

Table 32. Reg 19h Ramp Down Step Size MSB Register
BIT TYPE NAME W DEFLT DESCRIPTION

Represents MSB’s to define the step size for the ramp in down
[29:0] R/W Ramp Step Down MSB. 30 0
direction in ramp mode.

Table 33. Reg 1Ah Ramp Down Step Size LSB Register
BIT TYPE NAME W DEFLT DESCRIPTION

Represents LSB’s to define the step size for the ramp in down
[17:0] R/W Ramp Step Down LSB. 18 0
direction in ramp mode.

Information furnished by Analog Devices is believed to be accurate and reliable. However, no

For price, delivery and to place orders: For price, 2delivery, and to placeChelmsford,
orders: Analog MA
Devices, Inc.,
responsibility is assumed by Analog Devices for its use, nor for anyHittite Microwave
infringements Corporation,
of patents or other Elizabeth Drive, 01824
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106
rights of third parties that may result from its use. Specifications subject to change without notice. No
Phone: 978-250-3343 Fax: 978-250-3373 Phone:
license is granted by implication or otherwise under any patent or patent rights of Analog Devices.
Order781-329-4700
On-line at www.hittite.com
• Order online at www.analog.com 32
Trademarks and registered trademarks are Application Support:
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