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FEATURES
High Accuracy
0.1% Typical Error
High Speed
10 MHz Full-Power Bandwidth
450 V/ s Slew Rate
200 ns Settling to 0.1% at Full Power
Low Distortion
–80 dBc from Any Input
Third-Order IMD Typically –75 dBc at 10 MHz
Low Noise
94 dB SNR, 10 Hz to 20 kHz
70 dB SNR, 10 Hz to 10 MHz
Direct Division Mode
2 MHz BW at Gain of 100
APPLICATIONS
High Performance Replacement for AD534
Multiply, Divide, Square, Square Root
Modulator, Demodulator
Wideband Gain Control, RMS-DC Conversion
Voltage-Controlled Amplifiers, Oscillators, and Filters
Demodulator with 40 MHz Input Bandwidth
PRODUCT DESCRIPTION
X1 1
X INPUT
X2 2
U0 3
DENOMINATOR
INTERFACE
U1 4
10 MHz, 4-Quadrant
Multiplier/Divider
AD734
CONNECTION DIAGRAM
14-Lead DIP
(Q Package and N Package)
14 VP POSITIVE SUPPLY
13 DD DENOMINATOR DISABLE
AD734
12 W OUTPUT
Z INPUT
TOP VIEW 11 Z1
(Not to Scale)
10 Z2
U2 5
Y1 6
9 ER REFERENCE VOLTAGE
8 VN NEGATIVE SUPPLY
Y INPUT
Y2 7
demodulator with input frequencies as high as 40 MHz as long
as the desired output frequency is less than 10 MHz.
The AD734AQ and AD734BQ are specified for the industrial
temperature range of –40°C to +85°C and come in a 14-lead
ceramic DIP. The AD734SQ/883B, available processed to
MIL-STD-883B for the military range of –55°C to +125°C, is
available in a 14-lead ceramic DIP.
PRODUCT HIGHLIGHTS
The AD734 is an accurate high speed, four-quadrant analog
multiplier that is pin-compatible with the industry-standard
AD534 and provides the transfer function W = XY/U. The
AD734 provides a low-impedance voltage output with a full-
power (20 V pk-pk) bandwidth of 10 MHz. Total static error
(scaling, offsets, and nonlinearities combined) is 0.1% of full
scale. Distortion is typically less than –80 dBc and guaranteed.
The low capacitance X, Y and Z inputs are fully differential. In
most applications, no external components are required to
define the function.
The internal scaling (denominator) voltage U is 10 V, derived
from a buried-Zener voltage reference. A new feature provides
the option of substituting an external denominator voltage,
allowing the use of the AD734 as a two-quadrant divider with a
1000:1 denominator range and a signal bandwidth that remains
10 MHz to a gain of 20 dB, 2 MHz at a gain of 40 dB and
200 kHz at a gain of 60 dB, for a gain-bandwidth product of
200 MHz.
The advanced performance of the AD734 is achieved by a
combination of new circuit techniques, the use of a high speed
complementary bipolar process and a novel approach to laser-
trimming based on ac signals rather than the customary dc
methods. The wide bandwidth (>40 MHz) of the AD734’s
input stages and the 200 MHz gain-bandwidth product of the
multiplier core allow the AD734 to be used as a low distortion
REV. C
Information furnished by Analog Devices is believed to be accurate and
reliable. However, no responsibility is assumed by Analog Devices for its
use, nor for any infringements of patents or other rights of third parties
which may result from its use. No license is granted by implication or
otherwise under any patent or patent rights of Analog Devices.
The AD734 embodies more than two decades of experience in
the design and manufacture of analog multipliers, to provide:
1. A new output amplifier design with more than twenty times
the slew-rate of the AD534 (450 V/µs versus 20 V/µs) for a
full power (20 V pk-pk) bandwidth of 10 MHz.
2. Very low distortion, even at full power, through the use of
circuit and trimming techniques that virtually eliminate all of
the spurious nonlinearities found in earlier designs.
3. Direct control of the denominator, resulting in higher
multiplier accuracy and a gain-bandwidth product at small
denominator values that is typically 200 times greater than
that of the AD534 in divider modes.
4. Very clean transient response, achieved through the use of a
novel input stage design and wide-band output amplifier,
which also ensure that distortion remains low even at high
frequencies.
5. Superior noise performance by careful choice of device
geometries and operating conditions, which provide a
guaranteed 88 dB of dynamic range in a 20 kHz bandwidth.
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A.
Tel: 781/329-4700
World Wide Web Site: http://www.analog.com
Fax: 781/326-8703
© Analog Devices, Inc., 1999
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