The ISL28271 and ISL28272 are dual micropower instrumentation amplifiers (in-amps) optimized for low 2.4V to 5V single supplies. Both devices feature an Input Range Enhancement Circuit (IREC) which maintains CMRR performance for input voltages equal to the positive and negative supply rails. The input signal is capable of swinging 10% above the positive supply rail and to 100mV below the negative supply with only a slight degradation of the CMRR performance. The output operation is rail to rail. The ISL28271 is compensated for a minimum gain of 10 or more. For higher gain applications, the ISL28272 is compensated for a minimum gain of 100. The in-amps have CMOS input devices for maximum input common voltage range. The amplifiers can be operated from one lithium cell or two Ni-Cd batteries.
The ISL28271 and ISL28272 are dual micropower instrumentation amplifiers optimized for low 2.4 V to 5 V single‑supply operation. Both devices feature an Input Range Enhancement Circuit that maintains CMRR performance up to the supply rails, and they provide rail‑to‑rail input and output.
The datasheet includes absolute maximum ratings, thermal information, detailed electrical specifications, typical performance curves, package dimensions, and guidelines for preventing oscillation in unused channels.
| Typical supply current (both channels) | 120 µA |
|---|---|
| Maximum input bias current | 30 pA |
| CMRR | 100 dB |
| Offset voltage temperature coefficient | 0.7 µV/°C |
| Bandwidth (ISL28271) | 180 kHz (3 dB) |
| Bandwidth (ISL28272) | 100 kHz (3 dB) |
| Slew rate | 0.5 V/µs |
| Supply voltage range | 2.4 V to 5 V |
| Minimum gain (ISL28271) | 10 |
| Minimum gain (ISL28272) | 100 |
The ISL28271 is compensated for a minimum gain of 10.
It operates from a single supply of 2.4 V to 5 V.
Typical supply current is 120 µA for both channels.