Zero Drift, Precision Instrumentation Amplifier with Digitally Programmable Gain

The LTC6915 is a precision programmable gain instrumentation amplifier. The gain can be programmed to 0, 1, 2, 4, 8, 16, 32, 64, 128, 256, 512, 1024, 2048, or 4096 through a parallel or serial interface. The CMRR is typically 125dB with a single 5V supply with any programmed gain. The offset is below 10µV with a temperature drift of less than 50nV/°C.

The LTC6915 uses charge balanced sampled data techniques to convert a differential input voltage into a single ended signal that is in turn amplified by a zero-drift operational amplifier.

The differential inputs operate from rail-to-rail and the single-ended output swings from rail-to-rail. The LTC6915 can be used in single power supply applications as low as 2.7V, or with dual ±5V supplies. The LTC6915 is available in a 16-lead SSOP package and a 12-lead DFN surface mount package.

Applications

* Thermocouple Amplifiers

* Electronic Scales

* Medical Instrumentation

* Strain Gauge Amplifier

* High Resolution Data Acquisition

* 14 Levels of Programmable Gain

* 125dB CMRR Independent of Gain

* Gain Accuracy 0.1% (Typ)

* Maximum Offset Voltage of 10µV

* Maximum Offset Voltage Drift: 50nV/°C

* Rail-to-Rail Input and Output

* Parallel or Serial (SPI) Interface for Gain Setting

* Supply Operation: 2.7V to ±5.5V

* Typical Noise: 2.5µVP-P (0.01Hz to 10Hz)

* 16-Lead SSOP and 12-Lead DFN Packages