REV. C
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a
AD624
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A.
Tel: 781/329-4700 www.analog.com
Fax: 781/326-8703 © Analog Devices, Inc., 1999
Precision
Instrumentation Amplifier
PRODUCT DESCRIPTION
The AD624 is a high precision, low noise, instrumentation
amplifier designed primarily for use with low level transducers,
including load cells, strain gauges and pressure transducers. An
outstanding combination of low noise, high gain accuracy, low
gain temperature coefficient and high linearity make the AD624
ideal for use in high resolution data acquisition systems.
The AD624C has an input offset voltage drift of less than
0.25 µV/°C, output offset voltage drift of less than 10 µV/°C,
CMRR above 80 dB at unity gain (130 dB at G = 500) and a
maximum nonlinearity of 0.001% at G = 1. In addition to these
outstanding dc specifications, the AD624 exhibits superior ac
performance as well. A 25 MHz gain bandwidth product, 5 V/µs
slew rate and 15 µs settling time permit the use of the AD624 in
high speed data acquisition applications.
The AD624 does not need any external components for pre-
trimmed gains of 1, 100, 200, 500 and 1000. Additional gains
such as 250 and 333 can be programmed within one percent
accuracy with external jumpers. A single external resistor can
also be used to set the 624’s gain to any value in the range of 1
to 10,000.
PRODUCT HIGHLIGHTS
1. The AD624 offers outstanding noise performance. Input
noise is typically less than 4 nV/√Hz at 1 kHz.
2. The AD624 is a functionally complete instrumentation am-
plifier. Pin programmable gains of 1, 100, 200, 500 and 1000
are provided on the chip. Other gains are achieved through
the use of a single external resistor.
3. The offset voltage, offset voltage drift, gain accuracy and gain
temperature coefficients are guaranteed for all pretrimmed
gains.
4. The AD624 provides totally independent input and output
offset nulling terminals for high precision applications.
This minimizes the effect of offset voltage in gain ranging
applications.
5. A sense terminal is provided to enable the user to minimize
the errors induced through long leads. A reference terminal is
also provided to permit level shifting at the output.
FEATURES
Low Noise: 0.2 V p-p 0.1 Hz to 10 Hz
Low Gain TC: 5 ppm max (G = 1)
Low Nonlinearity: 0.001% max (G = 1 to 200)
High CMRR: 130 dB min (G = 500 to 1000)
Low Input Offset Voltage: 25 V, max
Low Input Offset Voltage Drift: 0.25 V/ⴗC max
Gain Bandwidth Product: 25 MHz
Pin Programmable Gains of 1, 100, 200, 500, 1000
No External Components Required
Internally Compensated
FUNCTIONAL BLOCK DIAGRAM
225.3⍀
124⍀
4445.7⍀
80.2⍀
50⍀
V
B
50⍀
20k⍀ 10k⍀
10k⍀
10k⍀
AD624
–INPUT
G = 100
G = 200
G = 500
RG
1
RG
2
+INPUT
SENSE
OUTPUT
REF
20k⍀ 10k⍀
