Ultra-precise current sense amplifiers in a compact footprint

06-08-2020 | Texas Instruments | Power

Texas Instruments INA290 Ultra-Precise Current Sense Amplifiers are capable of measuring voltage drops across shunt resistors over a broad common-mode range from 2.7V to 120V. The device is in a highly space-efficient SC-70 package with a PCB footprint of just 2mm x 2.1mm. The ultra-precise current measurement accuracy is accomplished thanks to the combination of an ultra-low offset voltage of ±12µV (maximum), a small gain error of ±0.1% (maximum), and a high DC CMRR of 160dB (typical). The device is not just designed for DC current measurement but also high-speed applications (including fast overcurrent protection, for example) with high bandwidth of 1MHz (at a gain of 20V/V) and an 85dB AC CMRR (at 50kHz).

The device runs from a single 2.7V to 20V supply and draws a 370µA supply current (typical). It is offered with five gain options: 20V/V, 50V/V, 100V/V, 200V/V, and 500V/V. The low offset of the zero-drift architecture allows current sensing with low ohmic shunts as specified over the wide operating temperature range (−40C to +125C).

Typical applications include active antenna systems mMIMO (AAS), macro remote radio units (RRU), 48V rack servers, 48V merchant network and server power supplies, and test and measurement fields.

By Natasha Shek