REV. D
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a
OP497
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., 2002
Precision Picoampere Input Current
Quad Operational Amplifier
FEATURES
Low Offset Voltage: 50 V max
Low Offset Voltage Drift: 0.5 V/ⴗC max
Very Low Bias Current
25ⴗC: 100 pA max
–55ⴗC to +125ⴗC: 450 pA max
Very High Open-Loop Gain: 2000 V/mV min
Low Supply Current (per Amplifier): 625 A max
Operates from ⴞ2 V to ⴞ20 V Supplies
High Common-Mode Rejection: 120 dB min
APPLICATIONS
Strain Gage and Bridge Amplifiers
High Stability Thermocouple Amplifiers
Instrumentation Amplifiers
Photo-Current Monitors
High Gain Linearity Amplifiers
Long-Term Integrators/Filters
Sample-and-Hold Amplifiers
Peak Detectors
Logarithmic Amplifiers
Battery-Powered Systems
GENERAL DESCRIPTION
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.
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.
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.
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.
PIN CONNECTIONS
16-Lead Wide Body SOIC
(S-Suffix)
1
2
3
4
5
6
7
8
16
15
14
13
12
11
10
9
–
+
NC = NO CONNECT
OUT A
–IN A
+IN A
V+
+IN B
–IN B
OUT B
OUT D
–IN D
+IN D
V–
+IN C
–IN C
OUT C
NC
NC
–
+
–
+
–
+
OP497
14-Lead Plastic Dip
(P-Suffix)
14-Lead Ceramic Dip
(Y-Suffix)
1
2
3
4
5
6
7
14
13
12
11
10
9
8
OUT A
–IN A
+IN A
V+
+IN B
–IN B
OUT B
OUT D
–IN D
+IN D
V–
+IN C
–IN C
OUT C
–
+
–
+
–
+
–
+
OP497
V
S
= ⴞ15V
V
CM
= 0V
1000
100
10
–75 –50 –25 0 25 50 75 100 125
INPUT CURRENT – PA
TEMPERATURE – C
–I
B
+I
B
I
OS
Input Bias, Offset Current vs. Temperature
