Micropower, Single Supply Rail-to-Rail Output Instrumentation Amplifier

The LT1789-1/LT1789-10 are micropower, precision instrumentation amplifiers that are optimized for single supply operation from 2.2V to 36V. The quiescent current is 95μA max, the inputs common mode to ground and the output swings within 110mV of ground. The gain is set with a single external resistor for a gain range of 1 to 1000 for the LT1789-1 and 10 to 1000 for the LT1789-10.

The high accuracy of the LT1789-1 (40ppm maximum nonlinearity and 0.25% max gain error) is unmatched by other micropower instrumentation amplifiers. The LT1789-10 maximizes both the input common mode range and dynamic output range when an amplification of 10 or greater is required, allowing precise signal processing where other instrumentation amplifiers fail to operate. The LT1789-1/LT1789-10 are laser trimmed for very low input offset voltage, low input offset voltage drift, high CMRR and high PSRR. The output can handle capacitive loads up to 400pF (LT1789-1), 1000pF (LT1789-10) in any gain configuration while the inputs are ESD protected up to 10kV (human body).

The LT1789-1/LT1789-10 are offered in the 8-pin SO package, requiring significantly less PC board area than discrete multi op amp and resistor designs.

Applications

* Portable Instrumentation

* Bridge Amplifiers

* Strain Gauge Amplifiers

* Thermocouple Amplifiers

* Differential to Single-Ended Converters

* Medical Instrumentation

* Micropower: 95μA Supply Current Max

* Low Input Offset Voltage: 100μV Max

* Low Input Offset Voltage Drift: 0.5μV/°C Max

* Single Gain Set Resistor:

* G = 1 to 1000 (LT1789-1)

* G = 10 to 1000 (LT1789-10)

* Inputs Common Mode to V–

* Wide Supply Range: 2.2V to 36V Total Supply

* CMRR at G = 10: 96dB Min

* Gain Error: G = 10, 0.25% Max

* Gain Nonlinearity: G = 10, 40ppm Max

* Input Bias Current: 40nA Max

* PSRR at G = 10: 100dB Min

* 1kHz Voltage Noise: 48nV/√Hz

* 0.1Hz to 10Hz Noise: 1.5μVP-P