Titles

INA1

®

28

INA128
INA129

INA1

29

INA1

28

INA1

29

Precision, Low Power
INSTRUMENTATION AMPLIFIERS
FEATURES

DESCRIPTION

q LOW OFFSET VOLTAGE: 50µV max

The INA128 and INA129 are low power, general
purpose instrumentation amplifiers offering excellent
accuracy. Their versatile 3-op amp design and small
size make them ideal for a wide range of applications.Current-feedback input circuitry provides wide bandwidth even at high gain (200kHz at G = 100).

q LOW DRIFT: 0.5µV/°C max
q LOW INPUT BIAS CURRENT: 5nA max
q HIGH CMR: 120dB min
q INPUTS PROTECTED TO ±40V
q WIDE SUPPLY RANGE: ±2.25 to ±18V

A single external resistor sets any gain from 1 to
10,000. INA128 provides an industry standard gain
equation; INA129’s gain equation is compatiblewith
the AD620.

q LOW QUIESCENT CURRENT: 700µA
q 8-PIN PLASTIC DIP, SO-8

The INA128/INA129 is laser trimmed for very low
offset voltage (50µV), drift (0.5µV/°C) and high common-mode rejection (120dB at G ≥ 100). It operates
with power supplies as low as ±2.25V, and quiescent
current is only 700µA—ideal for battery operated
systems. Internal input protection can withstand up to
±40Vwithout damage.

APPLICATIONS
q BRIDGE AMPLIFIER
q THERMOCOUPLE AMPLIFIER
q RTD SENSOR AMPLIFIER
q MEDICAL INSTRUMENTATION
q DATA ACQUISITION

The INA128/INA129 is available in 8-pin plastic
DIP, and SO-8 surface-mount packages, specified for
the –40°C to +85°C temperature range. The INA128
is also available in dual configuration, the INA2128.
V+
7

–

2

VIN

G=1+

A3
8VIN

INA129:

40kΩ

25kΩ(1)

RG

3

G=1+

A1
40kΩ

1

+

INA128:

INA128, INA129
Over-Voltage
Protection

6

50kΩ
RG
49.4kΩ
RG

VO

25kΩ(1)

Over-Voltage
Protection

5

A2
40kΩ

NOTE: (1) INA129: 24.7kΩ

Ref

40kΩ

4
V–

International Airport Industrial Park • Mailing Address: PO Box 11400, Tucson, AZ 85734 • Street Address: 6730 S. TucsonBlvd., 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

©1995 Burr-Brown Corporation

PDS-1296C

Printed in U.S.A. October, 1996

SPECIFICATIONS
At TA = +25°C, VS = ±15V, RL = 10kΩ, unless otherwisenoted.
INA128P, U
INA129P, U
PARAMETER

CONDITIONS

INPUT
Offset Voltage, RTI
Initial
TA = +25°C
vs Temperature
TA = TMIN to TMAX
vs Power Supply
VS = ±2.25V to ±18V
Long-Term Stability
Impedance, Differential
Common-Mode
VO = 0V
Common-Mode Voltage Range(1)
Safe Input Voltage
Common-Mode Rejection

VCM = ±13V, ∆RS = 1kΩ
G=1
G=10
G=100
G=1000

MIN

TYP

MAX

±50±500/G
±0.5 ± 20/G
±1 ±100/G

(V+) – 2
(V–) + 2

±10 ±100/G
±0.2 ± 2/G
±0.2 ±20/G
±0.1 ±3/G
1010 || 2
1011 || 9
(V+) – 1.4
(V–) + 1.7

80
100
120
120

86
106
125
130
±2
±30
±1
±30

BIAS CURRENT
vs Temperature
Offset Current
vs Temperature
NOISE VOLTAGE, RTI
f = 10Hz
f = 100Hz
f = 1kHz
fB = 0.1Hz to 10Hz
Noise Current
f=10Hz
f=1kHz
fB = 0.1Hz to 10Hz
GAINGain Equation, INA128
INA129
Range of Gain
Gain Error

Gain vs Temperature(2)
50kΩ (or 49.4kΩ) Resistance(2, 3)
Nonlinearity

OUTPUT
Voltage: Positive
Negative
Load Capacitance Stability
Short-Circuit Current

INA128PA, UA
INA129PA, UA
MIN

T
T
±40
73
93
110
110
±5

TYP

±25 ±100/G ±125 ±1000/G
±0.2 ± 5/G
±1 ± 20/G
T
±2 ±200/G
T
T
T
T
T
T
T
T
T
T
T
T
TT

±5

G = 1000, RS = 0Ω

MAX

UNITS

µV
µV/°C
µV/V
µV/mo
Ω || pF
Ω || pF
V
V
V
dB
dB
dB
dB

±10
±10

nA
pA/°C
nA
pA/°C

10
8
8
0.2

VO = ±13.6V, G=1
G=10
G=100
G=1000
RL = 10kΩ
RL = 10kΩ

(V+) – 1.4
(V–) + 1.4

T
T
T

pA/√Hz
pA/√Hz
pAp-p

1 + (50kΩ/RG)
1 + (49.4kΩ/RG)
1

nV/√Hz
nV/√Hz
nV/√Hz
µVp-p

0.9
0.3
30

G=1
G=10
G=100...