250 MHz, Voltage Output,

4-Quadrant Multiplier
Data Sheet AD835
FEATURES FUNCTIONAL BLOCK DIAGRAM
Simple: basic function is W = XY + Z X1 X = X1 – X2 AD835
Complete: minimal external components required X2
Very fast: Settles to 0.1% of full scale (FS) in 20 ns XY XY + Z
X1 W OUTPUT
DC-coupled voltage output simplifies use +
+
Y1
High differential input impedance X, Y, and Z inputs
Low multiplier noise: 50 nV/√Hz Y2 Y = Y1 – Y2

00883-001
Z INPUT

APPLICATIONS Figure 1.
Very fast multiplication, division, squaring
Wideband modulation and demodulation
Phase detection and measurement
Sinusoidal frequency doubling
Video gain control and keying
Voltage-controlled amplifiers and filters

GENERAL DESCRIPTION PRODUCT HIGHLIGHTS

The AD835 is a complete four-quadrant, voltage output analog 1. The AD835 is the first monolithic 250 MHz, four-quadrant
multiplier, fabricated on an advanced dielectrically isolated voltage output multiplier.
complementary bipolar process. It generates the linear product 2. Minimal external components are required to apply the
of its X and Y voltage inputs with a −3 dB output bandwidth of AD835 to a variety of signal processing applications.
250 MHz (a small signal rise time of 1 ns). Full-scale (−1 V to 3. High input impedances (100 kΩ||2 pF) make signal source
+1 V) rise to fall times are 2.5 ns (with a standard RL of 150 Ω), loading negligible.
and the settling time to 0.1% under the same conditions is 4. High output current capability allows low impedance loads
typically 20 ns. to be driven.
Its differential multiplication inputs (X, Y) and its summing 5. State-of-the-art noise levels achieved through careful
input (Z) are at high impedance. The low impedance output device optimization and the use of a special low noise,
voltage (W) can provide up to ±2.5 V and drive loads as low as band gap voltage reference.
25 Ω. Normal operation is from ±5 V supplies. 6. Designed to be easy to use and cost effective in applications
that require the use of hybrid or board-level solutions.
Though providing state-of-the-art speed, the AD835 is simple
to use and versatile. For example, as well as permitting the
addition of a signal at the output, the Z input provides the
means to operate the AD835 with voltage gains up to about ×10.
In this capacity, the very low product noise of this multiplier
(50 nV/√Hz) makes it much more useful than earlier products.
The AD835 is available in an 8-lead PDIP package (N) and an
8-lead SOIC package (R) and is specified to operate over the
−40°C to +85°C industrial temperature range.

Rev. E Document Feedback

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AD835 Data Sheet

TABLE OF CONTENTS
Features .............................................................................................. 1 Typical Performance Characteristics ..............................................7
Applications ....................................................................................... 1 Theory of Operation ...................................................................... 10
General Description ......................................................................... 1 Basic Theory ............................................................................... 10
Functional Block Diagram .............................................................. 1 Scaling Adjustment .................................................................... 10
Product Highlights ........................................................................... 1 Applications Information .............................................................. 11
Revision History ............................................................................... 2 Multiplier Connections ............................................................. 11
Specifications..................................................................................... 3 Wideband Voltage-Controlled Amplifier ............................... 11
Absolute Maximum Ratings ............................................................ 5 Amplitude Modulator ................................................................ 11
Thermal Resistance ...................................................................... 5 Squaring and Frequency Doubling .......................................... 12
ESD Caution .................................................................................. 5 Outline Dimensions ....................................................................... 13
Pin Configuration and Function Descriptions ............................. 6 Ordering Guide .......................................................................... 14

REVISION HISTORY
12/14—Rev. D to Rev. E
Changes to Figure 1 .......................................................................... 1
Changes to Figure 20 ...................................................................... 10
Changes to Wideband Voltage-Controlled Amplifier Section
and Figure 21 ................................................................................... 11
Changes to Ordering Guide .......................................................... 14

12/10—Rev. C to Rev. D
Changes to Figure 1 .......................................................................... 1
Changes to Absolute Maximum Ratings and Table 2 .................. 5
Added Figure 19, Renumbered Subsequent Tables .................... 10
Added Figure 23.............................................................................. 11

10/09—Rev. B to Rev. C
Updated Format .................................................................. Universal
Changes to Figure 22 ...................................................................... 11
Updated Outline Dimensions ....................................................... 13
Changes to Ordering Guide .......................................................... 14

6/03—Rev. A to Rev. B
Updated Format .................................................................. Universal
Updated Outline Dimensions ....................................................... 10

Rev. E | Page 2 of 14
Data Sheet AD835

SPECIFICATIONS
TA = 25°C, VS = ±5 V, RL = 150 Ω, CL ≤ 5 pF, unless otherwise noted.

Table 1.
Parameter Conditions Min Typ Max Unit
TRANSFER FUNCTION ( X1 − X 2 )(Y 1 − Y 2 )
W= +Z
U
INPUT CHARACTERISTICS (X, Y)
Differential Voltage Range VCM = 0 V ±1 V
Differential Clipping Level ±1.2 1 ±1.4 V
Low Frequency Nonlinearity X = ±1 V, Y = 1 V 0.3 0.51 % FS
Y = ±1 V, X = 1 V 0.1 0.31 % FS
vs. Temperature TMIN to TMAX 2
X = ±1 V, Y = 1 V 0.7 % FS
Y = ±1 V, X = 1 V 0.5 % FS
Common-Mode Voltage Range −2.5 +3 V
Offset Voltage ±3 ±201 mV
vs. Temperature TMIN to TMAX2 ±25 mV
CMRR f ≤ 100 kHz; ±1 V p-p 701 dB
Bias Current 10 201 µA
vs. Temperature TMIN to T
MAX
2
27 µA
Offset Bias Current 2 µA
Differential Resistance 100 kΩ
Single-Sided Capacitance 2 pF
Feedthrough, X X = ±1 V, Y = 0 V −461 dB
Feedthrough, Y Y = ±1 V, X = 0 V −601 dB
DYNAMIC CHARACTERISTICS
−3 dB Small Signal Bandwidth 150 250 MHz
−0.1 dB Gain Flatness Frequency 15 MHz
Slew Rate W = −2.5 V to +2.5 V 1000 V/µs
Differential Gain Error, X f = 3.58 MHz 0.3 %
Differential Phase Error, X f = 3.58 MHz 0.2 Degrees
Differential Gain Error, Y f = 3.58 MHz 0.1 %
Differential Phase Error, Y f = 3.58 MHz 0.1 Degrees
Harmonic Distortion X or Y = 10 dBm, second and third harmonic
Fund = 10 MHz −70 dB
Fund = 50 MHz −40 dB
Settling Time, X or Y To 0.1%, W = 2 V p-p 20 ns
SUMMING INPUT (Z)
Gain From Z to W, f ≤ 10 MHz 0.990 0.995
−3 dB Small Signal Bandwidth 250 MHz
Differential Input Resistance 60 kΩ
Single-Sided Capacitance 2 pF
Maximum Gain X, Y to W, Z shorted to W, f = 1 kHz 50 dB
Bias Current 50 µA

Rev. E | Page 3 of 14
AD835 Data Sheet
Parameter Conditions Min Typ Max Unit
OUTPUT CHARACTERISTICS
Voltage Swing ±2.2 ±2.5 V
vs. Temperature TMIN to TMAX2 ±2.0 V
Voltage Noise Spectral Density X = Y = 0 V, f < 10 MHz 50 nV/√Hz
Offset Voltage ±25 ±751 mV
vs. Temperature 3 TMIN to T MAX
2
±10 mV
Short-Circuit Current 75 mA
Scale Factor Error ±5 ±81 % FS
vs. Temperature TMIN to T MAX
2
±9 % FS
Linearity (Relative Error) 4 ±0.5 ±1.01 % FS
vs. Temperature TMIN to TMAX2 ±1.25 % FS
POWER SUPPLIES
Supply Voltage
For Specified Performance ±4.5 ±5 ±5.5 V
Quiescent Supply Current 16 251 mA
vs. Temperature TMIN to TMAX2 26 mA
PSRR at Output vs. VP +4.5 V to +5.5 V 0.51 %/V
PSRR at Output vs. VN −4.5 V to −5.5 V 0.5 %/V
1
All minimum and maximum specifications are guaranteed. These specifications are tested on all production units at final electrical test.
2
TMIN = −40°C, TMAX = 85°C.
3
Normalized to zero at 25°C.
4
Linearity is defined as residual error after compensating for input offset, output voltage offset, and scale factor errors.

Rev. E | Page 4 of 14
Data Sheet AD835

ABSOLUTE MAXIMUM RATINGS

Table 2. THERMAL RESISTANCE
Parameter Rating
Table 3.
Supply Voltage ±6 V
Package Type θJA θJC Unit
Internal Power Dissipation 300 mW
8-Lead PDIP (N) 90 35 °C/W
Operating Temperature Range −40°C to +85°C
8-Lead SOIC (R) 115 45 °C/W
Storage Temperature Range −65°C to +150°C
Lead Temperature, Soldering 60 sec 300°C
ESD Rating ESD CAUTION
HBM 1500 V
CDM 250 V

Stresses at or above those listed under Absolute Maximum

Ratings may cause permanent damage to the product. This is a
stress rating only; functional operation of the product at these
or any other conditions above those indicated in the operational
section of this specification is not implied. Operation beyond
the maximum operating conditions for extended periods may
affect product reliability.
For more information, see the Analog Devices, Inc., Tutorial
MT-092, Electrostatic Discharge.

Rev. E | Page 5 of 14
AD835 Data Sheet

PIN CONFIGURATION AND FUNCTION DESCRIPTIONS

Y1 1 8 X1
Y2 2
AD835 7 X2
TOP VIEW
VN 3 (Not to Scale) 6 VP

00883-002
Z 4 5 W

Figure 2. Pin Configuration

Table 4. Pin Function Descriptions

Pin No. Mnemonic Description
1 Y1 Noninverting Y Multiplicand Input
2 Y2 Inverting Y Multiplicand Input
3 VN Negative Supply Voltage
4 Z Summing Input
5 W Product
6 VP Positive Supply Voltage
7 X2 Inverting X Multiplicand Input
8 X1 Noninverting X Multiplicand Input

Rev. E | Page 6 of 14
Data Sheet AD835

TYPICAL PERFORMANCE CHARACTERISTICS

DG DP (NTSC) FIELD = 1 LINE = 18 Wfm → FCC COMPOSITE
0 0.06 0.11 0.16 0.19 0.20 X, Y CH = 0dBm
0.4
RL = 150Ω
CL ≤ 5pF
DIFFERENTIAL

0.2
GAIN (%)

MIN = 0 0
0

MAGNITUDE (dB)
MAX = 0.2
p-p/MAX = 0.2 –0.1
–0.2
–0.2
–0.4
1ST 2ND 3RD 4TH 5TH 6TH
–0.3
0 0.02 0.02 0.03 0.03 0.06
0.3 –0.4
PHASE (Degrees)

0.2
DIFFERENTIAL

–0.5
0.1

00883-006
0 –0.6
–0.1 MIN = 0

00883-003
MAX = 0.06
–0.2 300k 1M 10M 100M 1G
p-p = 0.06
–0.3
1ST 2ND 3RD 4TH 5TH 6TH FREQUENCY (Hz)

Figure 3. Typical Composite Output Differential Gain and Phase, Figure 6. Gain Flatness to 0.1 dB
NTSC for X Channel; f = 3.58 MHz, RL = 150 Ω

DG DP (NTSC) FIELD = 1 LINE = 18 Wfm → FCC COMPOSITE

0 0.01 0 0 –0.01 –0.20 X, Y CH = 5dBm
0.3
RL = 150Ω
0.2 MIN = –0.02 CL < 5pF
DIFFERENTIAL

MAX = 0.01
GAIN (%)

0.1 p-p/MAX = 0.03 –10

0 MAGNITUDE (dB)
–0.1 –20

–0.2 –30 Y FEEDTHROUGH

–0.3
1ST 2ND 3RD 4TH 5TH 6TH –40 X FEEDTHROUGH
0 0.03 0.04 0.07 0.10 0.16 –50
0.20 X FEEDTHROUGH
PHASE (DEGREES)
DIFFERENTIAL

–60
0.10
Y FEEDTHROUGH

00883-007
0 MIN = 0
MAX = 0.16
00883-004

–0.10 p-p = 0.16 1M 10M 100M 1G

–0.20 FREQUENCY (Hz)

1ST 2ND 3RD 4TH 5TH 6TH

Figure 4. Typical Composite Output Differential Gain and Phase, Figure 7. X and Y Feedthrough vs. Frequency
NTSC for Y Channel; f = 3.58 MHz, RL = 150 Ω

X, Y, Z CH = 0dBm
RL = 150Ω
CL ≤ 5pF
2 180 +0.2V
MAGNITUDE (dB)

PHASE (Degrees)

GAIN
0 90

–2 0 GND
PHASE
–4 –90

–6 –180 –0.2V

–8
00883-008
00883-005

–10 100mV 10ns

1M 10M 100M 1G
FREQUENCY (Hz)

Figure 5. Gain and Phase vs. Frequency of X, Y, Z Inputs Figure 8. Small Signal Pulse Response at W Output, RL = 150 Ω, CL ≤ 5 pF,
X Channel = ±0.2 V, Y Channel = ±1.0 V

Rev. E | Page 7 of 14
AD835 Data Sheet

10MHz

+1V

GND 10dB/DIV

–1V
30MHz
20MHz

00883-012
00883-009
500mV 10ns

Figure 9. Large Signal Pulse Response at W Output, RL = 150 Ω, CL ≤ 5 pF, Figure 12. Harmonic Distortion at 10 MHz; 10 dBm Input to X or Y Channels,
X Channel = ±1.0 V, Y Channel = ±1.0 V RL = 150 Ω, CL = ≤ 5 pF

50MHz

20
CMRR (dB)

40 10dB/DIV
100MHz 150MHz
60

80
00883-010

00883-013
1M 10M 100M 1G
FREQUENCY (Hz)

Figure 10. CMRR vs. Frequency for X or Y Channel, RL = 150 Ω, CL ≤ 5 pF Figure 13. Harmonic Distortion at 50 MHz, 10 dBm Input to X or Y Channel,
RL = 150 Ω, CL ≤ 5 pF

0dBm ON SUPPLY
X, Y = 1V
100MHz
PSSR ON V+
–10

–20
PSSR (dB)

–30
200MHz
300MHz
–40 10dB/DIV

–50 PSSR ON V–
–60
00883-011

00883-014

300k 1M 10M 100M 1G

FREQUENCY (Hz)

Figure 11. PSRR vs. Frequency for V+ and V– Supply Figure 14. Harmonic Distortion at 100 MHz, 10 dBm Input to X or Y Channel,
RL = 150 Ω, CL ≤ 5 pF

Rev. E | Page 8 of 14
Data Sheet AD835
35

X CH = 6dBm
30 Y CH = 10dBm
RL = 100Ω

THIRD ORDER INTERCEPT (dBm)

+2.5V 25

20
10dB/DIV

15

–2.5V 10

00883-015

00883-017
1V 10ns

0
0 20 40 60 80 100 120 140 160 180 200
RF FREQUENCY INPUT TO X CHANNEL (MHz)

Figure 15. Maximum Output Voltage Swing, RL = 50 Ω, CL ≤ 5 pF Figure 17. Fixed LO on Y Channel vs. RF Frequency Input to X Channel

15 35
OUTPUT OFFSET DRIFT WILL
TYPICALLY BE WITHIN SHADED AREA X CH = 6dBm
30 Y CH = 10dBm
10 RL = 100Ω

THIRD ORDER INTERCEPT (dBm)

VOS OUTPUT DRIFT (mV)

25
5

20
0
15

–5
10

–10
5
00883-016

00883-018
OUTPUT VOS DRIFT, NORMALIZED TO 0 AT 25°C
–15 0
–55 –35 –15 5 25 45 65 85 105 125 0 20 40 60 80 100 120 140 160 180 200
TEMPERATURE (°C) LO FREQUENCY ON Y CHANNEL (MHz)

Figure 16. VOS Output Drift vs. Temperature Figure 18. Fixed IF vs. LO Frequency on Y Channel

Rev. E | Page 9 of 14
AD835 Data Sheet

THEORY OF OPERATION
The AD835 is a four-quadrant, voltage output analog multiplier, avoid the needless use of less intuitive subscripted variables
fabricated on an advanced dielectrically isolated complementary (such as, VX1). All variables as being normalized to 1 V.
bipolar process. In its basic mode, it provides the linear product For example, the input X can either be stated as being in the −1 V
of its X and Y voltage inputs. In this mode, the −3 dB output to +1 V range or simply –1 to +1. The latter representation is found
voltage bandwidth is 250 MHz (with small signal rise time of 1 ns). to facilitate the development of new functions using the AD835.
Full-scale (−1 V to +1 V) rise to fall times are 2.5 ns (with a The explicit inclusion of the denominator, U, is also less helpful, as
standard RL of 150 Ω), and the settling time to 0.1% under the in the case of the AD835, if it is not an electrical input variable.
same conditions is typically 20 ns.
SCALING ADJUSTMENT
As in earlier multipliers from Analog Devices a unique
summing feature is provided at the Z input. As well as providing The basic value of U in Equation 1 is nominally 1.05 V. Figure 20,
independent ground references for the input and the output and which shows the basic multiplier connections, also shows how
enhanced versatility, this feature allows the AD835 to operate the effective value of U can be adjusted to have any lower
with voltage gain. Its X-, Y-, and Z-input voltages are all voltage (usually 1 V) through the use of a resistive divider
nominally ±1 V FS, with an overrange of at least 20%. The between W (Pin 5) and Z (Pin 4). Using the general resistor
inputs are fully differential at high impedance (100 kΩ||2 pF) values shown, Equation 1can be rewritten as
and provide a 70 dB CMRR (f ≤ 1 MHz). XY
W= + kW + (1 − k )Z ' (3)
The low impedance output is capable of driving loads as small U
as 25 Ω. The peak output can be as large as ±2.2 V minimum where Z' is distinguished from the signal Z at Pin 4. It follows that
for RL = 150 Ω, or ±2.0 V minimum into RL = 50 Ω. The AD835
XY
has much lower noise than the AD534 or AD734, making it W= + Z' (4)
attractive in low level, signal processing applications, for
(1 − k )U
example, as a wideband gain control element or modulator. In this way, the effective value of U can be modified to
BASIC THEORY U’ = (1 − k)U (5)
The multiplier is based on a classic form, having a translinear core, without altering the scaling of the Z' input, which is expected because
supported by three (X, Y, and Z) linearized voltage-to-current the only ground reference for the output is through the Z' input.
converters, and the load driving output amplifier. The scaling Therefore, to set U' to 1 V, remembering that the basic value of
voltage (the denominator U in the equations) is provided by a U is 1.05 V, R1 must have a nominal value of 20 × R2. The values
band gap reference of novel design, optimized for ultralow noise. shown allow U to be adjusted through the nominal range of
Figure 19 shows the functional block diagram. 0.95 V to 1.05 V. That is, R2 provides a 5% gain adjustment.
In general terms, the AD835 provides the function In many applications, the exact gain of the multiplier may not
( X1 − X 2 )(Y 1 − Y 2 ) be very important; in which case, this network may be omitted
W= +Z (1)
U entirely, or R2 fixed at 100 Ω.
FB 4.7µF TANTALUM
where the variables W, U, X, Y, and Z are all voltages. Connected as +5V
+

a simple multiplier, with X = X1 − X2, Y = Y1 − Y2, and Z = 0

and with a scale factor adjustment (see Figure 19) that sets U = 1 V, 0.01µF CERAMIC
X
the output can be expressed as W
8 7 6 5
W = XY (2) X1 X2 VP W
AD835 R1 = (1–k) R
2kΩ
X1 X = X1 – X2 AD835 Y1 Y2 VN Z
1 2 3 4
X2
Y
XY XY + Z +
X1 W OUTPUT
+ FB 4.7µF TANTALUM R2 = kR
+
+5V 200Ω
Y1
0.01µF CERAMIC
Y2 Y = Y1 – Y2 Z’
00883-020
00883-025

Z INPUT

Figure 19. Functional Block Diagram Figure 20. Multiplier Connections

Simplified representations of this sort, where all signals are

presumed expressed in V, are used throughout this data sheet to

Rev. E | Page 10 of 14
Data Sheet AD835

APPLICATIONS INFORMATION
The AD835 is easy to use and versatile. The capability for adding The ac response of this amplifier for gains of 0 dB (VG = 0.25 V),
another signal to the output at the Z input is frequently valuable. 6 dB (VG = 0.5 V), and 12 dB (VG = 1 V) is shown in Figure 22.
Three applications of this feature are presented here: a wideband In this application, the resistor values have been slightly adjusted to
voltage-controlled amplifier, an amplitude modulator, and a reflect the nominal value of U = 1.05 V. The overall sign of the
frequency doubler. Of course, the AD835 may also be used as a gain may be controlled by the sign of VG.
square law detector (with its X inputs and Y inputs connected in 21

parallel). In this mode, it is useful at input frequencies to well 18

over 250 MHz because that is the bandwidth limitation of the 15
12dB
output amplifier only. (VG = 1V)
12
MULTIPLIER CONNECTIONS 9

GAIN (dB)
6dB
Figure 20 shows the basic connections for multiplication. The 6
(VG = 0.5V)

inputs are often single sided, in which case the X2 and Y2 inputs 3 0dB
are normally grounded. Note that by assigning Pin 7 (X2) and (VG = 0.25V)
0
Pin 2 (Y2), respectively, to these (inverting) inputs, an extra
measure of isolation between inputs and output is provided. –3

The X and Y inputs may be reversed to achieve some desired –6

overall sign with inputs of a particular polarity, or they may be

00883-022
–9
10k 100k 1M 10M 100M
driven fully differentially. FREQUENCY (Hz)

Power supply decoupling and careful board layout are always Figure 22. AC Response of VCA
important in applying wideband circuits. The decoupling AMPLITUDE MODULATOR
recommendations shown in Figure 20 should be followed
closely. In Figure 21, Figure 23, and Figure 24, these power Figure 23 shows a simple modulator. The carrier is applied to the
supply decoupling components are omitted for clarity but should Y input and the Z input, while the modulating signal is applied to
be used wherever optimal performance with high speed inputs the X input. For zero modulation, there is no product term so the
is required. However, if the full, high frequency capabilities of the carrier input is simply replicated at unity gain by the voltage
AD835 are not being exploited, these components can be omitted. follower action from the Z input. At X = 1 V, the RF output is
doubled, while for X = –1 V, it is fully suppressed. That is, an
WIDEBAND VOLTAGE-CONTROLLED AMPLIFIER X input of approximately ±1 V (actually ±U or about 1.05 V)
Figure 21 shows the AD835 configured to provide a gain of corresponds to a modulation index of 100%. Carrier and
nominally 0 dB to 12 dB. (In fact, the control range extends from modulation frequencies can be up to 300 MHz, somewhat
well under –12 dB to about +14 dB.) R1 and R2 set the gain to beyond the nominal −3 dB bandwidth.
be nominally ×4. The attendant bandwidth reduction that comes Of course, a suppressed carrier modulator can be implemented
with this increased gain is partially offset by the addition of the by omitting the feedforward to the Z input, grounding that
peaking capacitor C1. Although this circuit shows the use of pin instead.
dual supplies, the AD835 can operate from a single 9 V supply
+5V
(such as a 9 V battery) with a slight revision. For G = 0 dB, omit
R1 and R2, and connect Pin Z directly to ground. Pin Z must be MODULATION
SOURCE 8 7 6 5 MODULATED
connected to a reference; otherwise, the output W floats to a rail. X1 X2 VP W CARRIER
OUTPUT
+5V AD835
Y1 Y2 VN Z
VG VOLTAGE 1 2 3 4
(GAIN CONTROL) OUTPUT
8 7 6 5
X1 X2 VP W R1
–5V
97.6Ω
AD835
C1 CARRIER
00883-026

Y1 Y2 VN Z 33pF SOURCE
1 2 3 4

VIN
Figure 23. Simple Amplitude Modulator Using the AD835
00883-021

(SIGNAL) R2
301Ω
–5V

Figure 21. Voltage-Controlled 50 MHz Amplifier Using the AD835

Rev. E | Page 11 of 14
AD835 Data Sheet
SQUARING AND FREQUENCY DOUBLING VG
+5V
C1
Amplitude domain squaring of an input signal, E, is achieved VOLTAGE
OUTPUT
simply by connecting the X and Y inputs in parallel to produce 8 7 6 5
X1 X2 VP W
an output of E2/U. The input can have either polarity, but the AD835 R2
97.6Ω
output in this case is always positive. The output polarity can be Y1 Y2 VN Z
reversed by interchanging either the X or Y inputs. 1 2 3 4

When the input is a sine wave E sin ωt, a signal squarer behaves
as a frequency doubler because R3

00883-024
R1
–5V 301Ω

( E sin ωt )2 E2
= (1 − cos 2ωt ) (6) Figure 24. Broadband Zero-Bounce Frequency Doubler
U 2U
This circuit is based on the identity
While useful, Equation 6 shows a dc term at the output, which
varies strongly with the amplitude of the input, E. 1
cos θ sin θ = sin 2θ (7)
2
Figure 24 shows a frequency doubler that overcomes this
limitation and provides a relatively constant output over a At ωO = 1/C1R1, the X input leads the input signal by 45° (and is
moderately wide frequency range, determined by the time attenuated by √2, while the Y input lags the input signal by 45°
constant R1C1. The voltage applied to the X and Y inputs is and is also attenuated by √2. Because the X and Y inputs are 90°
exactly in quadrature at a frequency f = ½πC1R1, and their out of phase, the response of the circuit is
amplitudes are equal. At higher frequencies, the X input becomes 1 E E E2
smaller while the Y input increases in amplitude; the opposite W= (sin ωt − 45°) (sin ωt + 45°) = (sin 2ωt ) (8)
U 2 2 2U
happens at lower frequencies. The result is a double frequency
output centered on ground whose amplitude of 1 V for a 1 V which has no dc component, R2 and R3 are included to restore
input varies by only 0.5% over a frequency range of ±10%. the output to 1 V for an input amplitude of 1 V (the same gain
Because there is no squared dc component at the output, sudden adjustment as previously mentioned). Because the voltage across
changes in the input amplitude do not cause a bounce in the dc level. the capacitor (C1) decreases with frequency, while that across
the resistor (R1) increases, the amplitude of the output varies
only slightly with frequency. In fact, it is only 0.5% below its full
value (at its center frequency ωO = 1/C1R1) at 90% and 110% of
this frequency.

Rev. E | Page 12 of 14
Data Sheet AD835

OUTLINE DIMENSIONS
0.400 (10.16)
0.365 (9.27)
0.355 (9.02)

8 5 0.280 (7.11)
0.250 (6.35)
1 0.240 (6.10)
4
0.325 (8.26)
0.310 (7.87)
0.100 (2.54) 0.300 (7.62)
BSC 0.060 (1.52) 0.195 (4.95)
0.210 (5.33) MAX 0.130 (3.30)
MAX 0.115 (2.92)
0.015
0.150 (3.81) (0.38) 0.015 (0.38)
0.130 (3.30) MIN GAUGE
0.115 (2.92) PLANE 0.014 (0.36)
SEATING
PLANE 0.010 (0.25)
0.022 (0.56) 0.008 (0.20)
0.005 (0.13) 0.430 (10.92)
0.018 (0.46) MIN MAX
0.014 (0.36)

0.070 (1.78)
0.060 (1.52)
0.045 (1.14)

COMPLIANT TO JEDEC STANDARDS MS-001

CONTROLLING DIMENSIONS ARE IN INCHES; MILLIMETER DIMENSIONS

070606-A
(IN PARENTHESES) ARE ROUNDED-OFF INCH EQUIVALENTS FOR
REFERENCE ONLY AND ARE NOT APPROPRIATE FOR USE IN DESIGN.
CORNER LEADS MAY BE CONFIGURED AS WHOLE OR HALF LEADS.

Figure 25. 8-Lead Plastic Dual In-Line Package [PDIP]

Narrow Body
(N-8)
Dimensions shown in inches and (millimeters)

5.00 (0.1968)
4.80 (0.1890)

8 5
4.00 (0.1574) 6.20 (0.2441)
3.80 (0.1497) 1 5.80 (0.2284)
4

1.27 (0.0500) 0.50 (0.0196)

BSC 45°
1.75 (0.0688) 0.25 (0.0099)
0.25 (0.0098) 1.35 (0.0532)
8°
0.10 (0.0040) 0°
COPLANARITY 0.51 (0.0201)
0.10 1.27 (0.0500)
0.31 (0.0122) 0.25 (0.0098)
SEATING 0.40 (0.0157)
PLANE 0.17 (0.0067)

COMPLIANT TO JEDEC STANDARDS MS-012-AA

CONTROLLING DIMENSIONS ARE IN MILLIMETERS; INCH DIMENSIONS
012407-A

(IN PARENTHESES) ARE ROUNDED-OFF MILLIMETER EQUIVALENTS FOR

REFERENCE ONLY AND ARE NOT APPROPRIATE FOR USE IN DESIGN.
Figure 26. 8-Lead Standard Small Outline Package [SOIC_N]
Narrow Body
(R-8)
Dimensions shown in millimeters and (inches)

Rev. E | Page 13 of 14
AD835 Data Sheet
ORDERING GUIDE
Model 1 Temperature Range Package Description Package Option
AD835ANZ −40°C to +85°C 8-Lead Plastic Dual In-Line Package [PDIP] N-8
AD835AR −40°C to +85°C 8-Lead Standard Small Outline Package [SOIC_N] R-8
AD835AR-REEL7 −40°C to +85°C 8-Lead Standard Small Outline Package [SOIC_N] R-8
AD835ARZ −40°C to +85°C 8-Lead Standard Small Outline Package [SOIC_N] R-8
AD835ARZ-REEL −40°C to +85°C 8-Lead Standard Small Outline Package [SOIC_N] R-8
AD835ARZ-REEL7 −40°C to +85°C 8-Lead Standard Small Outline Package [SOIC_N] R-8
1
Z = RoHS Compliant Part.

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registered trademarks are the property of their respective owners.
D00883-0-12/14(E)

Rev. E | Page 14 of 14