LT1168_06 Datasheet, PDF (1/20 Pages) Linear Technology – Low Power, Single Resistor Gain Programmable, Precision Instrumentation Amplifier

LT1168
FEATURES
Low Power, Single
Resistor Gain Programmable,
Precision Instrumentation Amplifier
DESCRIPTIO
■ _{Supply Current: 530µA Max}
■ _{Meets IEC 1000-4-2 Level 4 (±15kV) ESD Tests}
with Two External 5k Resistors
■ _{Single Gain Set Resistor: G = 1 to 10,000}
■ _{Gain Error: G = 10, 0.4% Max}
■ _{Input Offset Voltage Drift: 0.3µV/°C Max}
■ _{Gain Nonlinearity: G = 10, 20ppm Max}
■ _{Input Offset Voltage: 40µV Max}
■ _{Input Bias Current: 250pA Max}
■ _{PSRR at AV =1: 103dB Min}
■ _{CMRR at AV = 1: 90dB Min}
■ _{Wide Supply Range: ±2.3V to ±18V}
■ _{1kHz Voltage Noise: 10nV/√Hz}
■ _{0.1Hz to 10Hz Noise: 0.28µVP-P}
■ _{Available in 8-Pin PDIP and SO Packages}
U
APPLICATIO S
■ _{Bridge Amplifiers}
■ _{Strain Gauge Amplifiers}
■ _{Thermocouple Amplifiers}
■ _{Differential to Single-Ended Converters}
■ _{Differential Voltage to Current Converters}
■ _{Data Acquisition}
■ _{Battery-Powered and Portable Equipment}
■ _{Medical Instrumentation}
■ _Scales
The LT ^®1168 is a micropower, precision instrumentation am-
plifier that requires only one external resistor to set gains of
1 to 10,000. The low voltage noise of 10nV/√Hz (at 1kHz) is
not compromised by low power dissipation (350µA typical for
±15V supplies). The wide supply range of ±2.3V to ±18V allows
the LT1168 to fit into a wide variety of industrial as well as
battery-powered applications.
The high accuracy of the LT1168 is due to a 20ppm maximum
nonlinearity and 0.4% max gain error (G = 10). Previous mono-
lithic instrumentation amps cannot handle a 2k load resistor
whereas the nonlinearity of the LT1168 is specified for loads
as low as 2k. The LT1168 is laser trimmed for very low input
offset voltage (40µV max), drift (0.3µV/°C), high CMRR (90dB,
G = 1) and PSRR (103dB, G = 1). Low input bias currents of
250pA max are achieved with the use of superbeta process-
ing. The output can handle capacitive loads up to 1000pF in
any gain configuration while the inputs are ESD protected up
to 13kV (human body). The LT1168 with two external 5k
resistors passes the IEC 1000-4-2 level 4 specification.
The LT1168 is a pin-for-pin improved second source for the
AD620 and INA118. The LT1168, offered in 8-pin PDIP and
SO packages, requires significantly less PC board area than
discrete op amp resistor designs. These advantages make
the LT1168 the most cost effective solution for precision
instrumentation amplifier applications.
, LT, LTC and LTM are registered trademarks of Linear Technology Corporation.
All other trademarks are the property of their respective owners.
TYPICAL APPLICATIO
Single Supply* Pressure Monitor
BI TECHNOLOGIES
5V
67-8-3 R40KQ, (0.02% RATIO MATCH)
Gain Nonlinearity
1
3₊
40k
8
7
3.5k
3.5k
R1
G = 200
6
LT1168
249Ω
3.5k
3.5k
1
5
2_–
4
20k
3₊
1/2
1
40k
LT1112
2_–
*See Theory of Operation section
REF
IN
ADC
LTC^®1286
DIGITAL
DATA
OUTPUT
AGND
1168 TA01
G = 1000
R_L = 2k
V_OUT = ±10V
OUTPUT VOLTAGE (2V/DIV)
1168 TA01a
1168fa
1