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Circuit Note
CN-0025
Circuit Designs Using Analog Devices Products
Apply these product pairings quickly and with confidence.
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(1-800-262-5643) or visit www.analog.com/circuit.
Devices Connected/Referenced
AD5546 16-Bit Multiplying DAC
AD5556 14-Bit Multiplying DAC
AD8610 Precision Amplifier
Precision, AC Reference Signal Attenuator Using the
AD5546/AD5556 Multiplying DAC
Rev. 0
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engineers. Standard engineering practices have been employed in the design and construction of
each circuit, and their function and performance have been tested and verified in a lab environment
at room temperature. However, you are solely responsible for testing the circuit and determining its
suitability and applicability for your use and application. Accordingly, in no event shall Analog
Devices be liable for direct, indirect, special, incidental, consequential or punitive damages due to
any cause whatsoever connected to the use of any “Circuit from the Lab”. (Continued on last page)
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CIRCUIT FUNCTION AND BENEFITS
This circuit provides precision, ac signal attenuation using the
AD5546/AD5556 DAC and the AD8610 precision operational
amplifier. This circuit provides accurate, low noise, high speed
output voltage capability and is well suited for process control,
automatic test equipment, and digital calibration applications.
CIRCUIT DESCRIPTION
The AD5546/AD5556 are precision 16-/14-bit, multiplying, low
power, current output, parallel input DACs. They operate from
a single 2.7 V to 5.5 V supply with ±10 V multiplying references
for 4-quadrant outputs. Multiplying bandwidth is 4 MHz. Built
in 4-quadrant resistors facilitate resistance matching and
temperature tracking that minimize the number of components
needed for multiquadrant applications. Besides handling digital
waveforms decoded from parallel input data, the AD5546/
AD5556 handle low frequency ac reference signals for signal
attenuation, channel equalization, and waveform generation
applications.
08344-001
16/14-BIT
VDD
ROFS
ROFS
VOUT
RFB
RFB
C8
2.2pF
GND
U1
AD5546/AD5556
IOUT
R2R1
RCOMR1
16/14 DATA
REF
U2
AD8610
–
+
C4
0.1µF
C5
1µF
C6
0.1µF
C7
1µF
+12V
–12V
WR
WR
LDAC
LDAC
RS
RS
MSB
MSB
C2
0.1µF
C1
1µF
V+
V–
+5V
+10V
VIN
–10V
Figure 1. AC Signal Attenuation Configuration Using the AD5546/56 Precision DAC and the AD8610 Precision Op Amp (Simplified Schematic)