Precision Picoampere Input Current
Quad Operational Amplifier
OP497
FEATURES
Low offset voltage: 75 μV maximum
Low offset voltage drift: 1.0 μV/°C maximum
Very low bias current
25°C: 150 pA maximum
−40°C to +85°C: 300 pA maximum
Very high open-loop gain: 2000 V/mV minimum
Low supply current (per amplifier): 625 μA maximum
Operates from ±2 V to ±20 V supplies
High common-mode rejection: 114 dB minimum
PIN CONNECTIONS
OUT A
–IN A
+IN A
V+
+IN B
–IN B
OUT B
NC
1
2
3
4
5
6
7
8
16
15
14
OUT D
–IN D
+IN D
V–
+IN C
–IN C
OUT C
00309-001
00309-002
OP497
13
12
11
10
9
NC
NC = NO CONNECT
Figure 1. 16-Lead Wide Body SOIC (RW-16)
APPLICATIONS
Strain gage and bridge amplifiers
High stability thermocouple amplifiers
Instrumentation amplifiers
Photocurrent monitors
High gain linearity amplifiers
Long-term integrators/filters
Sample-and-hold amplifiers
Peak detectors
Logarithmic amplifiers
Battery-powered systems
INPUT CURRENT (pA)
OUT A
–IN A
+IN A
V+
+IN B
–IN B
OUT B
1
2
3
4
5
6
7
14
13
12
OUT D
–IN D
+IN D
V–
+IN C
–IN C
OUT C
OP497
11
10
9
8
Figure 2. 14-Lead PDIP (N-14)
1k
V
S
= ±15V
V
CM
= 0V
GENERAL DESCRIPTION
The OP497 is a quad op amp with precision performance in
the space-saving, industry standard 16-lead SOlC package.
Its combination 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
(<50 μV) and low drift (<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 its common-
mode rejection of >120 dB. The OP497 has a power supply
rejection of >120 dB which minimizes offset voltage changes
experienced in battery-powered systems. The supply current
of the OP497 is <625 μA per amplifier, and it can operate with
supply voltages as low as ±2 V.
The OP497 uses a superbeta input stage with bias current
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 25°C but double for every 10°C
rise in temperature to reach the nanoamp range above 85°C.
The input bias current of the OP497 is <100 pA at 25°C.
100
–I
B
+I
B
I
OS
–50
–25
0
25
50
75
100
125
00309-003
10
–75
TEMPERATURE (°C)
Figure 3. Input Bias, Offset Current vs. Temperature
Combining precision, low power, and low bias current, the OP497
is ideal for a number of applications, including instrumentation
amplifiers, log amplifiers, photodiode preamplifiers, and long-
term integrators. For a single device, see the
OP97
data sheet,
and for a dual device, see the
OP297
data sheet.
Rev. E
Information furnished by Analog Devices is believed to be accurate and reliable. However, no
responsibility is assumed by Analog Devices for its use, nor for any infringements of patents or other
rights of third parties that may result from its use. Specifications subject to change without notice. No
license is granted by implication or otherwise under any patent or patent rights of Analog Devices.
Trademarks and registered trademarks are the property of their respective owners.
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A.
Tel: 781.329.4700
www.analog.com
Fax: 781.461.3113 ©1991–2009 Analog Devices, Inc. All rights reserved.
OP497
TABLE OF CONTENTS
Features .............................................................................................. 1
Applications ....................................................................................... 1
General Description ......................................................................... 1
Pin Connections ............................................................................... 1
Revision History ............................................................................... 2
Specifications..................................................................................... 3
Absolute Maximum Ratings............................................................ 4
Thermal Resistance ...................................................................... 4
ESD Caution .................................................................................. 4
Typical Performance Characteristics ............................................. 5
Applications Information .............................................................. 10
AC Performance ......................................................................... 10
Guarding And Shielding ........................................................... 11
Open-Loop Gain Linearity ....................................................... 11
Applications Circuit ....................................................................... 12
Precision Absolute Value Amplifier ......................................... 12
Precision Current Pump ............................................................ 12
Precision Positive Peak Detector .............................................. 12
Simple Bridge Conditioning Amplifier ................................... 12
Nonlinear Circuits ...................................................................... 13
Outline Dimensions ....................................................................... 14
Ordering Guide .......................................................................... 15
REVISION HISTORY
2/09—Rev. D to Rev. E
Deleted 14-Lead CERDIP............................................. Throughout
Changes to Features Section and General Description
Section ................................................................................................ 1
Delete Military Processed Devices Text, SMD Part Number,
ADI Part Number Table, and Dice Characteristics Figure ......... 3
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
11/01—Rev. C to Rev. D
Edits to Pin Connection Headings ..................................................1
Deleted Wafer Test Limits ................................................................3
Edits to Absolute Maximum Ratings ..............................................5
Edits to Outline Dimensions......................................................... 16
Edits to Ordering Guide ................................................................ 17
Rev. E | Page 2 of 16
OP497
SPECIFICATIONS
T
A
= 25°C, V
S
= ±15 V, unless otherwise noted.
Table 1.
Parameter
INPUT CHARACTERISTICS
Offset Voltage
Average Input Offset Voltage Drift
Long-Term Input Offset Voltage
Stability
Input Bias Current
Average Input Bias Current Drift
Input Offset Current
Average Input Offset Current Drift
Input Voltage Range
1
Common-Mode Rejection
Large Signal Voltage Gain
Input Resistance Differential Mode
Input Resistance Common Mode
Input Capacitance
OUTPUT CHARACTERISTICS
Output Voltage Swing
Symbol
V
OS
TCV
OS
−40°C ≤ +85°C
T
MIN
− T
MAX
Condition
F Grade
Min
Typ
Max
40
70
0.4
0.1
40
60
0.3
30
50
0.3
±14
±13.5
135
120
4000
2000
30
500
3
±13.7
±14
±13.5
±25
135
120
525
580
75
150
1.0
G Grade
Min
Typ
Max
80
120
0.6
0.1
60
80
0.3
50
80
0.4
±14
±13.5
135
120
4000
2000
30
500
3
±13.7
±14
±13.5
±25
135
120
525
750
150
250
1.5
Unit
μV
μV
μV/°C
μV/Month
pA
pA
pA/°C
pA
pA
pA/°C
V
V
dB
dB
V/mV
V/mV
MΩ
GΩ
pF
V
V
V
mA
dB
dB
μA
μA
V
V
V/μs
kHz
dB
μV/p-p
nV/√Hz
nV/√Hz
fA/√Hz
I
B
TC
IB
I
OS
T
C
I
OS
IVR
CMR
A
VO
R
IN
R
INCM
C
IN
V
O
V
CM
= 0 V
−40° ≤ T
A
≤ +85°C
−40° ≤ T
A
≤ +85°C
V
CM
= 0 V
−40° ≤ T
A
≤ +85°C
±13
±13
114
108
1500
800
150
200
150
200
±13
±13
114
108
1200
800
200
300
200
300
T
MIN
− T
MAX
V
CM
= ±13 V
T
MIN
− T
MAX
V
O
= ±10 V, R
L
= 2 kΩ
−40° ≤ T
A
≤ +85°C
R
L
= 2 kΩ
R
L
= 10 kΩ, T
MIN
− T
MAX
R
L
= 10 kΩ
±13
±13
±13
±13
±13
±13
Short Circuit
POWER SUPPLY
Power Supply Rejection Ratio
Supply Current (per Amplifier)
Supply Voltage Range
DYNAMIC PERFORMANCE
Slew Rate
Gain Bandwidth Product
Channel Separation
NOISE PERFORMANCE
Voltage Noise
Voltage Noise Density
Current Noise Density
1
I
SC
PSRR
I
SY
V
S
V
S
= ±2 V to ±20 V
V
S
= ±2.5 V to ±20 V, T
MIN
− T
MAX
No load
T
MIN
− T
MAX
Operating range
T
MIN
− T
MAX
114
108
114
108
625
750
±20
±20
580
±2
±2.5
0.05
625
±20
±20
±2
±2.5
0.05
0.15
500
150
0.3
17
15
20
SR
GBW
CS
e
n
p-p
e
n
i
n
V
O
= 20 V p-p, f
O
= 10 Hz
0.1 Hz to 10 Hz
e
n
= 10 Hz
e
n
= 1 kHz
i
n
= 10 Hz
0.15
500
150
0.3
17
15
20
Guaranteed by CMR test.
Rev. E | Page 3 of 16
OP497
ABSOLUTE MAXIMUM RATINGS
Absolute maximum ratings apply to packaged parts.
Table 2.
Parameter
Supply Voltage
Input Voltage
1
Differential Input Voltage
1
Output Short-Circuit Duration
Storage Temperature Range
Operating Temperature Range
Junction Temperature Range
Lead Temperature (Soldering, 60 sec)
1
THERMAL RESISTANCE
θ
JA
is specified for the worst-case mounting conditions, that is,
θ
JA
is specified for a device in socket for the PDIP package, and
θ
JA
is specified for a device soldered to the printed circuit board
(PCB) for the SOIC package.
Table 3.
Package Type
14-Lead PDIP (N-14)
16-Lead SOIC (RW-16)
θ
JA
76
92
θ
JC
33
23
Unit
°C/W
°C/W
Rating
±20 V
20 V
40 V
Indefinite
−65°C to +150°C
−40°C to +85°C
−65°C to +150°C
300°C
For supply voltages less than ±20 V, the absolute maximum input voltage is
equal to the supply voltage.
–
1/4
OP497
+
2kΩ
V
1
20V p-p @ 10Hz
50kΩ
50Ω
–
Stresses above those listed under Absolute Maximum Ratings
may cause permanent damage to the device. This is a stress
rating only; functional operation of the device at these or any
other conditions above those indicated in the operational
section of this specification is not implied. Exposure to absolute
maximum rating conditions for extended periods may affect
device reliability.
OP497
+
1
(
V
2
/10,000
)
1/4
V
2
V
CHANNEL SEPARATION = 20 log
Figure 4. Channel Separation Test Circuit
ESD CAUTION
Rev. E | Page 4 of 16
00309-004
OP497
TYPICAL PERFORMANCE CHARACTERISTICS
T
A
= 25°C, V
S
= ±15 V, unless otherwise noted.
50
50
T
A
= 25°C
V
S
= ±15V
V
CM
= 0V
V
S
= ±15V
V
CM
= 0V
40
PERCENTAGE OF UNITS
00309-006
40
PERCENTAGE OF UNITS
30
30
20
20
10
10
–80
–60
–40
–20
0
20
40
60
80
100
0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
INPUT OFFSET VOLTAGE (µV)
TCV
OS
(µV/°C)
Figure 5. Typical Distribution of Input Offset Voltage
Figure 8. Typical Distribution of TCV
OS
50
1k
T
A
= 25°C
V
S
= ±15V
V
CM
= 0V
V
S
= ±15V
V
CM
= 0V
40
PERCENTAGE OF UNITS
INPUT CURRENT (pA)
30
100
20
–I
B
+I
B
I
OS
10
00309-007
–80
–60
–40
–20
0
20
40
60
80
100
–50
–25
0
25
50
75
100
125
INPUT BIAS CURRENT (pA)
TEMPERATURE (°C)
Figure 6. Typical Distribution of Input Bias Current
Figure 9. Input Bias, Offset Current vs. Temperature
60
70
50
T
A
= 25°C
V
S
= ±15V
V
CM
= 0V
INPUT BIAS CURRENT (pA)
T
A
= 25°C
V
S
= ±15V
–I
B
60
50
40
30
20
10
0
–15
PERCENTAGE OF UNITS
40
30
+I
B
20
10
0
00309-008
0
10
20
30
40
50
60
–10
–5
0
5
10
15
INPUT OFFSET CURRENT (pA)
COMMON-MODE VOLTAGE (V)
Figure 7. Typical Distribution of Input Offset Current
Figure 10. Input Bias Current vs. Common-Mode Voltage
Rev. E | Page 5 of 16
00309-011
00309-010
0
–100
10
–75
00309-009
0
–100
0