INA281A4IDBVR.pdf

Features 

Wide common-mode voltage: – Operational voltage: −4 V to +110 V – Survival voltage: −20 V to +120 V 

Excellent CMRR: – 120-dB DC CMRR – 65-dB AC CMRR at 50 kHz 

Accuracy: – Gain: • Gain error: ±0.5% (maximum) • Gain drift: ±20 ppm/°C (maximum) – Offset: • Offset voltage: ±55 µV (typical) • Offset drift: ±0.1 µV/°C (typical) 

Available gains: – INA281A1, INA281B1 : 20 V/V – INA281A2, INA281B2 : 50 V/V – INA281A3, INA281B3 : 100 V/V – INA281A4, INA281B4 : 200 V/V – INA281A5, INA281B5 : 500 V/V 

High bandwidth: 1.3 MHz 

Slew rate: 2.5V/µs 

Quiescent current: 1.5 mA

Description 

The INA281-Q1 is a high-precision current sense amplifier that can measure voltage drops across shunt resistors over a wide common-mode range from – 4 V to 110 V. 

The negative common-mode voltage allows the device to operate below ground, thus accommodating precise measurement of recirculating currents in half-bridge applications. 

The combination of a low offset voltage, small gain error and high DC CMRR enables highly accurate current measurement. 

The INA281-Q1 is not only designed for DC current measurement, but also for high-speed applications (like fast overcurrent protection, for example) with a high bandwidth of 1.3 MHz and an 65-dB AC CMRR (at 50 kHz). The INA281-Q1 operates from a single 2.7-V to 20- V supply, drawing 1.5 mA of supply current. The INA281-Q1 is available with five gain options: 20 V/V, 50 V/V, 100 V/V, 200 V/V, and 500 V/V.

These gain options address wide dynamic range for currentsensing applications. 

The INA281-Q1 is specified over an operating temperature range of −40 °C to +125 °C and is offered in a space-saving SOT-23 package with two pin-out variants

Applications 

 Active antenna system mMIMO (AAS) 

 Macro remote radio unit (RRU) 

 48-V rack server 

 48-V merchant network & server power supply (PSU) 

 Solenoid control • Valve control 

 Telecom equipment 

 Power supplies