1997 Burr-Brown Corporation
PDS-1361B
Printed in U.S.A., February, 1998
INA125
INSTRUMENTATION AMPLIFIER
With Precision Voltage Reference
FEATURES
q
LOW QUIESCENT CURRENT: 460
A
q
PRECISION VOLTAGE REFERENCE:
1.24V, 2.5V, 5V or 10V
q
SLEEP MODE
q
LOW OFFSET VOLTAGE: 250
V max
q
LOW OFFSET DRIFT: 2
V/
C max
q
LOW INPUT BIAS CURRENT: 20nA max
q
HIGH CMR: 100dB min
q
LOW NOISE: 38nV/
Hz at f = 1kHz
q
INPUT PROTECTION TO
40V
q
WIDE SUPPLY RANGE
Single Supply: 2.7V to 36V
Dual Supply:
1.35V to
18V
q
16-PIN DIP AND SO-16 SOIC PACKAGES
APPLICATIONS
q
PRESSURE AND TEMPERATURE BRIDGE
AMPLIFIERS
q
INDUSTRIAL PROCESS CONTROL
q
FACTORY AUTOMATION
q
MULTI-CHANNEL DATA ACQUISITION
q
BATTERY OPERATED SYSTEMS
q
GENERAL PURPOSE INSTRUMENTATION
DESCRIPTION
The INA125 is a low power, high accuracy instrumen-
tation amplifier with a precision voltage reference. It
provides complete bridge excitation and precision dif-
ferential-input amplification on a single integrated
circuit.
A single external resistor sets any gain from 4 to
10,000. The INA125 is laser-trimmed for low offset
voltage (250
V), low offset drift (2
V/
C), and high
common-mode rejection (100dB at G = 100). It oper-
ates on single (+2.7V to +36V) or dual (
1.35V to
18V) supplies.
The voltage reference is externally adjustable with pin-
selectable voltages of 2.5V, 5V, or 10V, allowing use
with a variety of transducers. The reference voltage is
accurate to
0.5% (max) with
35ppm/
C drift (max).
Sleep mode allows shutdown and duty cycle operation
to save power.
The INA125 is available in 16-pin plastic DIP and
SO-16 surface-mount packages and is specified for
the 40
C to +85
C industrial temperature range.
A
1
Ref
Amp
10V
A
2
30k
10k
10k
30k
Bandgap
V
REF
13
12
1
14
15
16
4
6
9
10
11
IA
REF
5
8
7
R
G
Sense
R
R
2R
4R
INA125
V
REF
COM
V
REF
BG
V
REF
2.5
V
REF
5
V
REF
10
V
REF
Out
V
IN
V+
+
V
IN
2
SLEEP
3
V
V
O
= (V
IN
V
IN
) G
G = 4 + 60k
+
R
G
V
O
INA125
INA125
International Airport Industrial Park Mailing Address: PO Box 11400, Tucson, AZ 85734 Street Address: 6730 S. Tucson Blvd., Tucson, AZ 85706 Tel: (520) 746-1111 Twx: 910-952-1111
Internet: http://www.burr-brown.com/ FAXLine: (800) 548-6133 (US/Canada Only) Cable: BBRCORP Telex: 066-6491 FAX: (520) 889-1510 Immediate Product Info: (800) 548-6132
SBOS060
2
INA125
SPECIFICATIONS: V
S
=
15V
At T
A
= +25
C, V
S
=
15V, IA common = 0V, V
REF
common = 0V, and R
L
= 10k
, unless otherwise noted.
INA125P, U
INA125PA, UA
The information provided herein is believed to be reliable; however, BURR-BROWN assumes no responsibility for inaccuracies or omissions. BURR-BROWN assumes
no responsibility for the use of this information, and all use of such information shall be entirely at the user's own risk. Prices and specifications are subject to change
without notice. No patent rights or licenses to any of the circuits described herein are implied or granted to any third party. BURR-BROWN does not authorize or warrant
any BURR-BROWN product for use in life support devices and/or systems.
PARAMETER
CONDITIONS
MIN
TYP
MAX
MIN
TYP
MAX
UNITS
INPUT
Offset Voltage, RTI
Initial
50
250
T
500
V
vs Temperature
0.25
2
T
5
V/
C
vs Power Supply
V
S
=
1.35V to
18V, G = 4
3
20
T
50
V/V
Long-Term Stability
0.2
T
V/mo
Impedance, Differential
10
11
|| 2
T
|| pF
Common-Mode
10
11
|| 9
T
|| pF
Safe Input Voltage
40
T
V
Input Voltage Range
See Text
T
Common-Mode Rejection
V
CM
= 10.7V to +10.2V
G = 4
78
84
72
T
dB
G = 10
86
94
80
T
dB
G = 100
100
114
90
T
dB
G = 500
100
114
90
T
dB
BIAS CURRENT
V
CM
= 0V
10
25
T
50
nA
vs Temperature
60
T
pA/
C
Offset Current
0.5
2.5
T
5
nA
vs Temperature
0.5
T
pA/
C
NOISE, RTI
R
S
= 0
Voltage Noise, f = 10Hz
40
T
nV/
Hz
f = 100Hz
38
T
nV/
Hz
f = 1kHz
38
T
nV/
Hz
f
= 0.1Hz to 10Hz
0.8
T
Vp-p
Current Noise, f = 10Hz
170
T
fA/
Hz
f
= 1kHz
56
T
fA/
Hz
f = 0.1Hz to 10Hz
5
T
pAp-p
GAIN
Gain Equation
4 + 60k
/R
G
T
V/V
Range of Gain
4
10,000
T
T
V/V
Gain Error
V
O
= 14V to +13.3V
G = 4
0.01
0.075
T
0.1
%
G = 10
0.03
0.3
T
0.5
%
G = 100
0.05
0.5
T
1
%
G = 500
0.1
T
%
Gain vs Temperature
G = 4
1
15
T
T
ppm/
C
G > 4
(1)
25
100
T
T
ppm/
C
Nonlinearity
V
O
= 14V to +13.3V
G = 4
0.0004
0.002
T
0.004
% of FS
G = 10
0.0004
0.002
T
0.004
% of FS
G = 100
0.001
0.01
T
T
% of FS
G = 500
0.002
T
% of FS
OUTPUT
Voltage: Positive
(V+)1.7
(V+)0.9
T
T
V
Negative
(V)+1
(V)+0.4
T
T
V
Load Capacitance Stability
1000
T
pF
Short-Circuit Current
9/+12
T
mA
VOLTAGE REFERENCE
V
REF
= +2.5V, +5V, +10V
Accuracy
I
L
= 0
0.15
0.5
T
1
%
vs Temperature
I
L
= 0
18
35
T
100
ppm/
C
vs Power Supply, V+
V+ = (V
REF
+ 1.25V) to +36V
20
50
T
100
ppm/V
vs Load
I
L
= 0 to 5mA
3
75
T
T
ppm/mA
Dropout Voltage, (V+) V
REF
(2)
Ref Load = 2k
1.25
1
T
T
V
Bandgap Voltage Reference
1.24
T
V
Accuracy
I
L
= 0
0.5
T
%
vs Temperature
I
L
= 0
18
T
ppm/
C
3
INA125
INA125P, U
INA125PA, UA
PARAMETER CONDITIONS
MIN
TYP
MAX
MIN
TYP
MAX
UNITS
FREQUENCY RESPONSE
Bandwidth, 3dB
G = 4
150
T
kHz
G = 10
45
T
kHz
G = 100
4.5
T
kHz
G = 500
0.9
T
kHz
Slew Rate
G = 4, 10V Step
0.2
T
V/
s
Settling Time, 0.01%
G = 4, 10V Step
60
T
s
G = 10, 10V Step
83
T
s
G = 100, 10V Step
375
T
s
G = 500, 10V Step
1700
T
s
Overload Recovery
50% Overdrive
5
T
s
POWER SUPPLY
Specified Operating Voltage
15
T
V
Specified Voltage Range
1.35
18
T
T
V
Quiescent Current, Positive
I
O
= I
REF
= 0mA
460
525
T
T
A
Negative
I
O
= I
REF
= 0mA
280
325
T
T
A
Reference Ground Current
(3)
180
T
A
Sleep Current (V
SLEEP
100mV)
R
L
= 10k
, Ref Load = 2k
1
25
T
T
A
SLEEP MODE PIN
(4)
V
IH
(Logic high input voltage)
+2.7
V+
T
T
V
V
IL
(Logic low input voltage)
0
+0.1
T
T
V
I
IH
(Logic high input current)
15
T
A
I
IL
(Logic low input current)
0
T
A
Wake-up Time
(5)
150
T
s
TEMPERATURE RANGE
Specification Range
40
+85
T
T
C
Operation Range
55
+125
T
T
C
Storage Range
55
+125
T
T
C
Thermal Resistance,
JA
16-Pin DIP
80
T
C/W
SO-16 Surface-Mount
100
T
C/W
T
Specification same as INA125P, U.
NOTES: (1) Temperature coefficient of the "Internal Resistor" in the gain equation. Does not include TCR of gain-setting resistor, R
G
. (2) Dropout voltage is the
positive supply voltage minus the reference voltage that produces a 1% decrease in reference voltage. (3) V
REF
COM pin. (4) Voltage measured with respect to
Reference Common. Logic low input selects Sleep mode. (5) IA and Reference, see Typical Performance Curves.
SPECIFICATIONS: V
S
=
15V
(CONT)
At T
A
= +25
C, V
S
=
15V, IA common = 0V, V
REF
common = 0V, and R
L
= 10k
, unless otherwise noted.
INA125P, U
INA125PA, UA
PARAMETER
CONDITIONS
MIN
TYP
MAX
MIN
TYP
MAX
UNITS
INPUT
Offset Voltage, RTI
Initial
75
500
T
750
V
vs Temperature
0.25
T
V/
C
vs Power Supply
V
S
= +2.7V to +36V
3
20
T
50
V/V
Input Voltage Range
See Text
T
Common-Mode Rejection
V
CM
= +1.1V to +3.6V
G = 4
78
84
72
T
dB
G = 10
86
94
80
T
dB
G = 100
100
114
90
T
dB
G = 500
100
114
90
T
dB
GAIN
Gain Error
V
O
= +0.3V to +3.8V
G = 4
0.01
T
%
OUTPUT
Voltage, Positive
(V+)1.2
(V+)0.8
T
T
V
Negative
(V)+0.3
(V)+0.15
T
T
V
POWER SUPPLY
Specified Operating Voltage
+5
T
V
Operating Voltage Range
+2.7
+36
T
T
V
Quiescent Current
I
O
= I
REF
= 0mA
460
525
T
T
A
Sleep Current (V
SLEEP
100mV)
R
L
= 10k
, Ref Load = 2k
1
25
T
T
A
T
Specification same as INA125P, U.
SPECIFICATIONS: V
S
= +5V
At T
A
= +25
C, V
S
= +5V, IA common at V
S
/2, V
REF
common = V
S
/2, V
CM
= V
S
/2, and R
L
= 10k
to V
S
/2, unless otherwise noted.
4
INA125
PIN CONFIGURATION
Top View
16-Pin DIP, SO-16
Power Supply Voltage, V+ to V ........................................................ 36V
Input Signal Voltage ..........................................................................
40V
Output Short Circuit ................................................................. Continuous
Operating Temperature ................................................. 55
C to +125
C
Storage Temperature ..................................................... 55
C to +125
C
Lead Temperature (soldering, 10s) ............................................... +300
C
NOTE: Stresses above these ratings may cause permanent damage.
ABSOLUTE MAXIMUM RATINGS
(1)
V+
SLEEP
V
V
REF
OUT
IA
REF
V
IN
V
IN
R
G
V
REF
10
V
REF
5
V
REF
2.5
V
REF
BG
V
REF
COM
Sense
V
O
R
G
1
2
3
4
5
6
7
8
16
15
14
13
12
11
10
9
+
ELECTROSTATIC
DISCHARGE SENSITIVITY
This integrated circuit can be damaged by ESD. Burr-Brown
recommends that all integrated circuits be handled with ap-
propriate precautions. Failure to observe proper handling and
installation procedures can cause damage.
ESD damage can range from subtle performance degradation
to complete device failure. Precision integrated circuits may
be more susceptible to damage because very small parametric
changes could cause the device not to meet its published
specifications.
PACKAGE INFORMATION
PACKAGE DRAWING
PRODUCT
PACKAGE
NUMBER
(1)
INA125PA
16-Pin Plastic DIP
180
INA125P
16-Pin Plastic DIP
180
INA125UA
SO-16 Surface-Mount
265
INA125U
SO-16 Surface-Mount
265
NOTES: (1) For detailed drawing and dimension table, please see end of data
sheet, or Appendix C of Burr-Brown IC Data Book.
5
INA125
TYPICAL PERFORMANCE CURVES
At T
A
= +25
C and V
S
=
15V, unless otherwise noted.
GAIN vs FREQUENCY
60
50
40
30
20
10
0
Gain (dB)
Frequency (Hz)
1
10
100
1k
10k
100k
1M
G = 500
G = 100
G = 10
G = 4
COMMON-MODE REJECTION vs FREQUENCY
120
100
80
60
40
20
0
Common-Mode Rejection (dB)
Frequency (Hz)
1
10
100
1k
10k
100k
1M
G = 100, 500
G = 4
G = 10
G = 500
G = 100
INPUT COMMON-MODE VOLTAGE
vs OUTPUT VOLTAGE, V
S
= 5V
Output Voltage (V)
Input Common-Mode Voltage (V)
5
4
5
3
2
1
0
1
2
3
4
5
4
3
2
1
0
1
2
3
4
5
Limited by A
2
output swing--see text
Limited by A
2
output swing--see text
V
S
= 5V
V
S
= +5V
IA
REF
= 0V
POSITIVE POWER SUPPLY REJECTION
vs FREQUENCY
140
120
100
80
60
40
20
Power Supply Rejection (dB)
Frequency (Hz)
1
10
100
1k
10k
100k
1M
G = 4
G = 10
G = 500
G = 100
NEGATIVE POWER SUPPLY REJECTION
vs FREQUENCY
120
100
80
60
40
20
0
Power Supply Rejection (dB)
Frequency (Hz)
1
10
100
1k
10k
100k
1M
G = 4
G = 10
G = 100
G = 500
INPUT COMMON-MODE VOLTAGE
vs OUTPUT VOLTAGE, V
S
= 15V
Output Voltage (V)
Input Common-Mode Voltage (V)
15
10
0
5
15
5
15
10
5
0
5
10
15
10
V
D/2
+
+
V
CM
V
O
V
D/2
IA
REF
15V
+15V
+
Limited by A
2
output swing--see text
Limited by A
2
output swing--see text
PDF 
ZIP