Precision Picoampere Input Current
Quad Operational Amplifier
OP497
FEATURES PIN CONNECTIONS
Low offset voltage: 75 V maximum OUT A 1 16
OUT D
Low offset voltage drift: 1.0 V/C maximum IN A 2 15 IN D
3
Very low bias current +IN A 14 +IN D
V+ 4 13 V
25C: 150 pA maximum OP497
5
+IN B 12 +IN C
40C to +85C: 300 pA maximum
IN B 6 11
IN C
Very high open-loop gain: 2000 V/mV minimum
OUT B 7 10 OUT C
Low supply current (per amplifier): 625 A maximum
8
NC 9 NC
Operates from 2 V to 20 V supplies
High common-mode rejection: 114 dB minimum NC = NO CONNECT
Figure 1. 16-Lead Wide Body SOIC (RW-16)
APPLICATIONS
OUT A 1 14
OUT D
Strain gage and bridge amplifiers
IN A 2 13 IN D
High stability thermocouple amplifiers
3
+IN A 12 +IN D
Instrumentation amplifiers
V+ 4 11 V
OP497
Photocurrent monitors
+IN B 5 10 +IN C
High gain linearity amplifiers IN B 6 9
IN C
Long-term integrators/filters OUT B 7 8 OUT C
Sample-and-hold amplifiers
Figure 2. 14-Lead PDIP (N-14)
Peak detectors
1k
Logarithmic amplifiers
V = 15V
S
V = 0V
CM
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.
100
Its combination of exceptional precision with low power and
extremely low input bias current makes the quad OP497 useful I
B
in a wide variety of applications.
+I
B
Precision performance of the OP497 includes very low offset
I
(<50 V) and low drift (<0.5 V/C). Open-loop gain exceeds OS
10
2000 V/mV ensuring high linearity in every application. Errors
75 50 25 0 25 50 75 100 125
due to common-mode signals are eliminated by its common-
TEMPERATURE (C)
mode rejection of >120 dB. The OP497 has a power supply
Figure 3. Input Bias, Offset Current vs. Temperature
rejection of >120 dB which minimizes offset voltage changes
Combining precision, low power, and low bias current, the OP497
experienced in battery-powered systems. The supply current
is ideal for a number of applications, including instrumentation
of the OP497 is <625 A per amplifier, and it can operate with
amplifiers, log amplifiers, photodiode preamplifiers, and long-
supply voltages as low as 2 V.
term integrators. For a single device, see the OP97 data sheet,
The OP497 uses a superbeta input stage with bias current
and for a dual device, see the OP297 data sheet.
cancellation 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 25C but double for every 10C
rise in temperature to reach the nanoamp range above 85C.
The input bias current of the OP497 is <100 pA at 25C.
Rev. E
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INPUT CURRENT (pA)
00309-002 00309-001
00309-003OP497
TABLE OF CONTENTS
Features .............................................................................................. 1 AC Performance ......................................................................... 10
Applications ....................................................................................... 1 Guarding And Shielding ........................................................... 11
General Description ......................................................................... 1 Open-Loop Gain Linearity ....................................................... 11
Pin Connections ............................................................................... 1 Applications Circuit ....................................................................... 12
Revision History ............................................................................... 2 Precision Absolute Value Amplifier ......................................... 12
Specif icat ions ..................................................................................... 3 Precision Current Pump ............................................................ 12
Absolute Maximum Ratings ............................................................ 4 Precision Positive Peak Detector .............................................. 12
Thermal Resistance ...................................................................... 4 Simple Bridge Conditioning Amplifier ................................... 12
ESD Caution .................................................................................. 4 Nonlinear Circuits ...................................................................... 13
Typical Performance Characteristics ............................................. 5 Outline Dimensions ....................................................................... 14
Applications Information .............................................................. 10 Ordering Guide .......................................................................... 15
REVISION HISTORY
2/09Rev. D to Rev. E 11/01Rev. C to Rev. D
Deleted 14-Lead CERDIP ............................................. Throughout Edits to Pin Connection Headings .................................................. 1
Changes to Features Section and General Description Deleted Wafer Test Limits ................................................................ 3
Section ................................................................................................ 1 Edits to Absolute Maximum Ratings .............................................. 5
Delete Military Processed Devices Text, SMD Part Number, Edits to Outline Dimensions ......................................................... 16
ADI Part Number Table, and Dice Characteristics Figure ......... 3 Edits to Ordering Guide ................................................................ 17
Changes to Table 1 ............................................................................ 3
Changes to Absolute Maximum Ratings Section ......................... 4
Changes to Figure 12 ........................................................................ 6
Changes to Figure 18 and Figure 19 ............................................... 7
Changes to Figure 26 and Figure 28 ............................................... 8
Deleted OP497 Spice Macro-Model Section ............................... 10
Changes to Applications Information Section ............................ 10
Moved Figure 33 ............................................................................. 10
Deleted Table I. OP497 SPICE Net-List....................................... 11
Changes to Open-Loop Gain Linearity Section and
Figure 35 .......................................................................................... 11
Changes to Figure 40 ...................................................................... 13
Updated Outline Dimensions ....................................................... 14
Changes to Ordering Guide .......................................................... 15
Rev. E | Page 2 of 16