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.