Precision Picoampere Input Current
Quad Operational Amplifier
a
OP497
FEATURES
PIN CONNECTIONS
Low Offset Voltage: 50 V max
Low Offset Voltage Drift: 0.5 V/؇C max
Very Low Bias Current
16-Lead Wide Body SOIC
(S-Suffix)
25؇C: 100 pA max
–55؇C to +125؇C: 450 pA max
OUT D
–IN D
+IN D
OUT A
–IN A
1
2
3
4
5
16
15
14
13
12
11
Very High Open-Loop Gain: 2000 V/mV min
Low Supply Current (per Amplifier): 625 A max
Operates from ؎2 V to ؎20 V Supplies
High Common-Mode Rejection: 120 dB min
–
–
+
+
+
–
–
+IN A
V+
V–
OP497
+IN C
+IN B
–IN B
OUT B
NC
APPLICATIONS
+
–IN C
6
7
8
Strain Gage and Bridge Amplifiers
High Stability Thermocouple Amplifiers
Instrumentation Amplifiers
Photo-Current Monitors
10 OUT C
NC
9
NC = NO CONNECT
High Gain Linearity Amplifiers
Long-Term Integrators/Filters
Sample-and-Hold Amplifiers
Peak Detectors
Logarithmic Amplifiers
Battery-Powered Systems
14-Lead Plastic Dip
(P-Suffix)
14-Lead Ceramic Dip
(Y-Suffix)
GENERAL DESCRIPTION
OUT A
1
2
3
4
5
6
7
14 OUT D
The OP497 is a quad op amp with precision performance in the
space-saving, industry standard 16-lead SOlC package. Its com-
bination of exceptional precision with low power and extremely
low input bias current makes the quad OP497 useful in a wide
variety of applications.
–IN A
+IN A
V+
–IN D
13
12
–
–
+
+
–
–
+IN D
11 V–
OP497
+IN C
+IN B
–IN B
OUT B
10
9
+
+
–IN C
Precision performance of the OP497 includes very low offset,
under 50 µV, and low drift, below 0.5 µV/°C. Open-loop gain
exceeds 2000 V/mV ensuring high linearity in every application.
Errors due to common-mode signals are eliminated by the OP497’s
common-mode rejection of over 120 dB. The OP497’s power
supply rejection of over 120 dB minimizes offset voltage changes
experienced in battery-powered systems. Supply current of the
OP497 is under 625 µA per amplifier, and it can operate with
supply voltages as low as 2 V.
OUT C
8
1000
V
V
= ؎15V
= 0V
S
CM
The OP497 utilizes a superbeta input stage with bias current can-
cellation to maintain picoamp bias currents at all temperatures.
This is in contrast to FET input op amps whose bias currents start
in the picoamp range at 25°C, but double for every 10°C rise in
temperature, to reach the nanoamp range above 85°C. Input bias
current of the OP497 is under 100 pA at 25°C and is under 450
pA over the military temperature range.
100
–I
B
+I
B
I
OS
10
Combining precision, low power, and low bias current, the
OP497 is ideal for a number of applications, including instru-
mentation amplifiers, log amplifiers, photo-diode preamplifiers,
and long-term integrators. For a single device, see the OP97; for a
dual device, see the OP297.
–75
–50
–25
0
25
50
75
100
125
TEMPERATURE –
C
Input Bias, Offset Current vs. Temperature
REV. D
Information furnished by Analog Devices is believed to be accurate and
reliable. However, no responsibility is assumed by Analog Devices for its
use, norforanyinfringementsofpatentsorotherrightsofthirdpartiesthat
may result from its use. No license is granted by implication or otherwise
under any patent or patent rights of Analog Devices.
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Tel: 781/329-4700
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www.analog.com
© Analog Devices, Inc., 2002