® ®

ADS-30639
Dual, 14-Bit, 6.4MHz
Sampling A/D Converter

FEATURES
• 14-bit resolution
• 6.4MHz sampling rate
• Functionally complete
• No missing codes over full military temperature range
• Edge-triggered, 1.7 Watts
• Small, 28-pin, ceramic DDIP
• Ideal for both time and frequency-domain applications INPUT/OUTPUT CONNECTIONS
PIN FUNCTION PIN FUNCTION
GENERAL DESCRIPTION
The low-cost ADS-30639 is a dual 14-bit, 6.4MHz sampling 1 INPUT "A" 28 INPUT "B"
A/D converter. This device accurately samples full-scale input 2 RANGE 27 –5V
signals up to Nyquist frequencies with no missing codes. The 3 +2.5V REFERENCE 26 +15V
dynamic performance of the ADS-30639 has been optimized to 4 ANALOG GROUND 25 +5VD
achieve a signal-to-noise ratio (SNR) of 78dB and a total 5 +5VA 24 DIGITAL GROUND
harmonic distortion (THD) of –80dB. Each channel is 6 START CONVERT "A" 23 START CONVERT "B"
completely independant allowing operation with independant 7 SELECT 22 ENABLE
analog inputs and start convert signals. 8 BIT 14 (LSB) 21 BIT 1 (MSB)
Packaged in a miniature 28-pin DDIP, the functionally complete 9 BIT 13 20 BIT 2
ADS-30639 contains two individual fast-settling sample-hold 10 BIT 12 19 BIT 3
amplifiers and subranging A/D converters, along with an 11 BIT 11 18 BIT 4
internal reference, timing/control logic, and error-correction 12 BIT 10 17 BIT 5
circuitry. Digital input and output levels are TTL. The ADS- 13 BIT 9 16 BIT 6
30639 only requires the rising edge of the start convert pulse 14 BIT 8 15 BIT 7
to operate.
Requiring only ±5V and +15V supplies, the ADS-30639 calibrating, error-correcting circuit enables the device to
dissipates 1.7 Watts. The device is offered with a bipolar achieve specified performance over the full military
(±2.0V) analog input range. Model is available for use in –55 temperature range. Typical applications include medical
to +125°C operating temperature range. A proprietary, auto- imaging, radar, sonar, communications and instrumentation.

SUBRANGING
ANALOG INPUT "A" 1 T/H A/D 8 BIT 14 (LSB)
"A"
9 BIT 13
10 BIT 12
DIGITAL CORRECTION LOGIC

3-STATE OUTPUT REGISTER

POWER AND GROUNDING 11 BIT 11

12 BIT 10
+5V ANALOG SUPPLY 5 13 BIT 9
+5V DIGITAL SUPPLY 25 14 BIT 8
15 BIT 7
+15V SUPPLY 26
16 BIT 6
–5V SUPPLY 27 17 BIT 5
ANALOG GROUND 4 18 BIT 4
19 BIT 3
DIGITAL GROUND 24
20 BIT 2
21 BIT 1 (MSB)
SUBRANGING
ANALOG INPUT "B" 28 T/H A/D
"B"

START CONVERT "A" 6 TIMING AND

CONTROL 7 SELECT
START CONVERT "B" 23 LOGIC
22 ENABLE

Figure 1. ADS-30639 Functional Block Diagram

DATEL, Inc., Mansfield, MA 02048 (USA) • Tel: (508)339-3000, (800)233-2765 Fax: (508)339-6356 • E-mail: sales@datel.com • Internet: www.datel.com
This datasheet has been downloaded from http://www.digchip.com at this page
 ® ®

ADS-30639

ABSOLUTE MAXIMUM RATINGS PHYSICAL/ENVIRONMENTAL

PARAMETERS LIMITS UNITS PARAMETERS MIN. TYP. MAX. UNITS

+5V Supply (Pins 5, 25) 0 to +6 Volts Operating Temp. Range, Case

+15V Supply (Pin 26) 12 to 17 Volts ADS-30639 –55 — +125 °C
–5V Supply (Pin 27) 0 to –6 Volts Thermal Impedance
Digital Inputs (Pins 6, 7, 22, 23 ) –0.3 to +VDD +0.3 Volts θjc — 6 — °C/Watt
θca — 23 — °C/Watt
Analog Input (Pins 1, 28) ±5 Volts Storage Temperature Range –65 — +150 °C
Lead Temperature (10 seconds) +300 °C
Package Type 28-pin, metal-sealed, ceramic DDIP
Weight

FUNCTIONAL SPECIFICATIONS
(TA = +25°C, +VDD = +5V, –VDD = –5V, +Vcc = +15V, 6.4MHz sampling rate, ±2V input range, and a minimum 3 minute warmup À , Á unless otherwise specified.)
+25°C 0 to +70°C –55 to +125°C
ANALOG INPUT MIN. TYP. MAX. MIN. TYP. MAX. MIN. TYP. MAX. UNITS
Bipolar Input Voltage Range  — ±2 — — ±2 — — ±2 — Volts
Input Resistance (Vin A), (Vin B) 380 400 420 380 400 420 380 400 420 Ω
Input Capacitance — 6 15 — 6 15 — 6 15 pF

DIGITAL INPUT

Logic Levels
Logic "1" +2.0 — — +2.0 — — +2.0 — — Volts
Logic "0" — — +0.8 — — +0.8 — — +0.8 Volts
Logic Loading "1" — — +20 — — +20 — — +20 µA
Logic Loading "0" — — –20 — — –20 — — –20 µA
Start Convert Positive Pulse Width à — 50 — — 50 — — 50 — ns
Input Capacitance CIN — 10 15 — 10 15 — 10 15 pf

STATIC PERFORMANCE

Resolution — 14 — — 14 — — 14 — Bits
Integral Nonlinearity (DC Input) — ±1 — — ±2 — — ±3 — LSB
Differential Nonlinearity (fin = 10kHz) –0.90 ±0.5 +1 –0.90 ±0.5 +1 –0.99 ±0.5 +1.25 LSB
Full Scale Absolute Accuracy — ±0.1 ±0.3 — ±0.15 ±0.5 — ±0.5 ±0.8 %FSR
Bipolar Zero Error (Tech Note 2) — ±0.3 ±0.5 — ±0.3 ±0.5 — ±0.5 ±0.9 %FSR
Gain Error (Tech Note 2) — ±0.3 ±0.5 — ±0.3 ±0.5 — ±0.5 ±0.9 %FSR
No Missing Codes (fin = 10kHz) 14 — — 14 — — 14 — — Bits

DYNAMIC PERFORMANCE

Peak Harmonics (–0.5dB)

dc to 975kHz — –80 –78 — –80 –78 — –80 –76 dB
975kHz to 2.4MHz — –76 –70 — –76 –70 — –76 –68 dB
Total Harmonic Distortion (–0.5dB)
dc to 975kHz — –80 –77 — –80 –77 — –80 –74 dB
975kHz to 2.4MHz — –75 –69 — –75 –69 — –75 –67 dB
Signal-to-Noise Ratio
(w/o distortion, –0.5dB)
dc to 975kHz 76 78 — 76 78 — 75 77 — dB
975kHz to 2.4MHz 75 77 — 75 77 — 74 76 — dB
Signal-to-Noise Ratio Ä
(& distortion, –0.5dB)
dc to 975kHz 74 74 — 74 74 — 73 73 — dB
975kHz to 2.4MHz 68 72 — 68 72 — 67 72 — dB
Noise — 150 — — 150 — — 150 — µVrms
Two-tone Intermodulation
Distortion (fin = 240kHz, 200kHz
fs = 6.4MHz, –0.5dB) — –76 –70 — –76 –70 — –76 –70 dB
Input Bandwidth (–3dB)
Small Signal (–20dB input) — 30 — — 30 — — 30 — MHz
Large Signal (–0.5dB input) — 20 — — 20 — — 20 — MHz
Feedthrough Rejection (fin = 500kHz) — 78 — — 78 — — 78 — dB
Slew Rate — ±450 — — ±450 — — ±450 — V/µs
Aperture Delay Time — +1 — — +1 — — +1 — ns
Aperture Uncertainty — 5 — — 5 — — 5 — ps rms

2
 ® ®

ADS-30639

+25°C 0 to +70°C –55 to +125°C

DYNAMIC PERFORMANCE (Cont.) MIN. TYP. MAX. MIN. TYP. MAX. MIN. TYP. MAX. UNITS
S/H Acquisition Time
( to ±0.003%FSR, 5V step) — 45 — — 45 — — 45 — ns
Overvoltage Recovery Time — 175 — — 175 — — 175 — ns
A/D Conversion Rate 6.4 — — 6.4 — — 6.4 — — MHz

DIGITAL OUTPUTS

Logic Levels
Logic "1" +2.4 — Vcc +2.4 — Vcc +2.4 — Vcc Volts
Logic "0" GND — +0.4 GND — +0.4 GND — +0.4 Volts
Logic Loading "1" — — –4 — — –4 — — –4 mA
Logic Loading "0" — — +4 — — +4 — — +4 mA
Output Coding Two’s Complement
Output Capacitance COUT — — 15 — — 15 — — 15 pf

Tri-State Output Leakage Current IOZ — — ±20 — — ±20 — — ±20 µA

POWER REQUIREMENTS

Power Supply Ranges

+5V Supply Å +4.9 +5.0 +5.25 +4.9 +5.0 +5.25 +4.9 +5.0 +5.25 Volts
–5V Supply –4.5 –5.0 –5.5 –4.5 –5.0 –5.5 –4.5 –5.0 –5.5 Volts
+15V Supply +13.5 +15 +16.5 +13.5 +15 +16.5 +13.5 +15 +16.5 Volts
Power Supply Currents
+5V Supply — 220 270 — 220 270 — 220 270 mA
–5V Supply — 25 35 — 25 35 — 25 35 mA
+15V Supply — 20 35 — 20 35 — 20 35 mA
Power Dissipation — 1.7 1.9 — 1.7 1.9 — 1.7 1.9 Watts
Power Supply Rejection — — ±0.05 — — ±0.05 — — ±0.05 %FSR/%V

Footnotes:

À All power supplies should be on before applying a start convert pulse. All Ä Effective bits is equal to:
Full Scale Amplitude
supplies and the clock (start convert pulses) must be present during warmup (SNR + Distortion) – 1.76 + 20 log
periods. The device must be continuously converting during this time. Actual Input Amplitude

Á During the 3-minute warm up period there is a slight offset and gain drift but 6.02
the dynamic specifications of the ADS-30639 are not affected. Å +5 VA and 5 VD supplies are connected internally.
 Contact DATEL for other input voltage ranges.
à A 50% duty cycle start convert pulse is used for all production testing. For
applications requiring less than an 6.4MHz sampling rate, wider start convert pulses
can be used. A 50% duty cycle is recommended for all sampling fequencies.

TECHNICAL NOTES
1. Obtaining fully specified performance from the ADS-30639 2. The ADS-30639 achieves its specified accuracies without
requires careful attention to pc card layout and power the need for external calibration. It is recommended that
supply decoupling. The device’s analog and digital ground the +5VA and +5VD supplies should be powered up from
systems are connected to each other internally. For optimal the same source.
performance, tie all ground pins (4 and 24) directly to a
large analog ground plane beneath the package. 3. A passive bandpass filter is used at the input of the A/D for
all production testing.
Bypass all power supplies to ground with 4.7 F tantalum
capacitors in parallel with 0.1 F ceramic capacitors. Locate
the bypass capacitors as close to the unit as possible.

3
 ® ®

ADS-30639

THERMAL REQUIREMENTS
All DATEL sampling A/D converters are fully characterized and See Ordering Information for the assigned part number. See
specified over operating temperature (case) range of page 1-183 of the DATEL Data Acquisition Components Catalog
–55 to +125°C. All room temperature (TA = +25°C) production for more information on the HS Series. Request DATEL
testing is performed without the use of heat sinks or forced air Application Note AN8, "Heat Sinks for DIP Data Converters", or
cooling. Thermal impedance figures for each device are listed contact DATEL directly, for additional information.
in their respective specification tables.
These devices do not normally require heat sinks, however, Table 1. Output Coding
standard precautionary design and layout procedures should
be used to ensure devices do not overheat. The ground and INPUT VOLT. BIPOLAR
power planes beneath the package, as well as all pcb signal MSB LSB ±2V SCALE
runs to and from the device, should be as heavy as possible to
01 1111 1111 1111 +1.99976 +FS – 1LSB
help conduct heat away from the package.
01 1000 0000 0000 +1.50000 +3/4FS
Electrically-insulating, thermally-conductive "pads" may be 01 0000 0000 0000 +1.00000 +1/2FS
installed underneath the package. Devices should be soldered 00 0000 0000 0000 0.00000 0
to boards rather than socketed, and of course, minimal air flow 11 0000 0000 0000 –1.00000 –1/2FS
over the surface can greatly help reduce the package 10 1000 0000 0000 –1.50000 –3/4FS
temperature. 10 0000 0000 0001 –1.99976 –FS+1LSB
10 0000 0000 0000 –2.00000 –FS
In more severe ambient conditions, the package/junction
temperature of a given device can be reduced dramatically
TWO’S COMP
(typically 35%) by using one of DATEL's HS Series heat sinks.

Original Specification
VDD = +5V, CL=60pF Min(ns) Max(ns) Typ(ns)
Tpwh Minimum convert pulse width high 45 — 80
Tpwl Minimum convert pulse width low 45 — 80
Tnctdv New conversion to internal data valid (Internal) 8 20 12
Toetdv Output enable to data valid 20 40 30
Tseltdv Select change to data valid 20 40 25
Tdctdv Internal data to data valid (Internal) 8 18 12
Todtdz Output disable to high-impedence 30 45 35
Tctdv Conversion to data valid 16 38 24

sample (n)
taken on
rising edge Tpwh Tpwl

START
CONVERT
A&B

ENABLE

SELECT
Tctdv Tseltdv Tseltdv Tctdv Todtdz Toetdv

DATA ON An-3 Bn-3 An-3 An-2 An-2

BUS

Channel Channel Channel

A Selected B Selected A Selected

Figure 2. Timing Diagram

4
 ®
Male BNC

P1
DC25S
13
Male BNC 100
1 28

®
Input A Input B 74AS573
21 19 MSB
2 MSB D1 Q1
20 18
100 Range B2 D2 Q2
10uF 3 19 17
+ +2.5V REF B3 D3 Q3
18 16
+ 10uF B4 D4 Q4
17 15
ADS-30639
ADS-30465 B5
16
D5 Q5
14
B6 D6 Q6
15 13
B7 D7 Q7
14
B8 EN VCC OE
26 13
+15V B9 11 20 1.10
10uF 27 12
+15V + B10
–5V 11
–5V 10uF 6 B11 +5V
+ Start Con A 10 2 19
B12 D1 Q1
23 9
Start Con B B13 3 18
8 D2 74AS573 Q2
7 Select LSB 4 17
D3 Q3
A, B 5 16
Gnd Enable +5VA +5VD D4 Q4 14
6 15 1
5 25 D5 Q5
4 24 22 7 14
5

D6 Q6
8 13 LSB
D7 Q7
+5V + 9 12
12 10uF EN VCC OE
9 11
1 8 74S86 20 1.10
4 3 74S86 11
6 74S86 + +5V
74S86 13 +5V
2 10
10uF +5V
5 7 14

+5V +5V

14
+5V 10 74ACT74
+5V
12
Select A
74ACT74 D PR Q 9
14 4
2 5 11 C Q 8
D PR Q CL Select B
XTAL
8 3
12.8M C 6
MHz Q 7 13 200
CL
7 1 200 +5V

ADS-30639
+5V

Figure 3. ADS-30639 Connection Diagram

 ® ®

ADS-30639

MECHANICAL DIMENSIONS
INCHES (mm)

1.570 MAX.
(39.88) Dimension Tolerances (unless otherwise indicated):
2 place decimal (.XX) ±0.010 (±0.254)
3 place decimal (.XXX) ±0.005 (±0.127)
Lead Material: Kovar alloy
28 15
Lead Finish: 50 microinches (minimum) gold plating
0.80 MAX. over 100 microinches (nominal) nickel plating
(20.32)

1 14

0.100 TYP.
(2.540)

1.300 TYP.
(33.00)

0.210 MAX.
(5.334) PIN 1 INDEX
( ON TOP)
0.200 MAX.
(5.080)

0.012 ±0.003
(0.305)
0.185 MAX.
(4.70)
0.018 ±0.002 0.100 0.100 0.100
(0.457) (2.540) (2.540) 0.600 ±0.010 (2.540)
SEATING
0.040 PLANE (15.240)
(10.160) 0.025
(0.635)

ORDERING INFORMATION
OPERATING 28-PIN
MODEL TEMP. RANGE PACKAGE
ADS-30639 –55 to +125°C DDIP

® ®

INNOVATION and EXCELLENCE

ISO 9001
R E G I S T E R E D
DS-0438D 03/00

DATEL, Inc. 11 Cabot Boulevard, Mansfield, MA 02048-1151 DATEL (UK) LTD. Tadley, England Tel: (01256)-880444
Tel: (508) 339-3000 (800) 233-2765 Fax: (508) 339-6356 DATEL S.A.R.L. Montigny Le Bretonneux, France Tel: 1-34-60-01-01
Internet: www.datel.com E-mail:sales@datel.com DATEL GmbH München, Germany Tel: 89-544334-0
Data Sheet Fax Back: (508) 261-2857 DATEL KK Tokyo, Japan Tel: 3-3779-1031, Osaka Tel: 6-354-2025
DATEL makes no representation that the use of its products in the circuits described herein, or the use of other technical information contained herein, will not infringe upon existing or future patent rights. The descriptions contained herein
do not imply the granting of licenses to make, use, or sell equipment constructed in accordance therewith. Specifications are subject to change without notice. The DATEL logo is a registered DATEL, Inc. trademark.