Texas Instruments INA791A Current Sense Amplifier

Texas Instruments INA791A Current Sense Amplifier is designed to monitor bidirectional current over a common-mode range of -4V to 110V, independent of the supply voltage. This amplifier is a voltage output, current sense amplifier with an integrated shunt resistor of 400μΩ. The INA791A amplifier operates at 1 MHz with a high small-signal bandwidth. This current sense amplifier features an excellent Common Mode Rejection Ratio (CMRR) of 160dB DC CMRR and 114dB AC CMRR at 50kHz. The INA791A device operates from a single 2.7V to 5.5V power supply, drawing a maximum of 4.25mA of supply current. This amplifier operates at an extended temperature range of -40°C to 125°C and is available in a 15-pin VQFN package. The INA791A amplifier is ideal for 48V DC/DC converters, 48V Battery Management Systems (BMS), test and measurement, 48V rack servers, and 48V merchant networks.

Features

  • Precision design with integrated shunt resistor:
    • ±75A continuous current at 25°C
    • ±50A continuous current at 125°C
    • 400µΩ shunt resistor
    • 2nH shunt inductance
  • -4V to 110V wide common-mode voltage range
  • 1MHz high small signal bandwidth
  • Excellent CMRR:
    • 160dB DC CMRR
    • 114dB AC CMRR at 50kHz
  • High measurement accuracy:
    • ±0.35%, ±35ppm/°C drift 100 system gain error (maximum)
    • ±40mA, ±70mA over temperature offset current (maximum)
  • 20mV/A to 400mV/A adjustable gain with external resistor divider network
  • Open-drain temperature alert at TJ of 160°C

Applications

  • 48V DC/DC converters
  • 48V Battery Management Systems (BMS)
  • Test and measurement
  • Macro Remote Radio Unit (RRU)
  • 48V rack server
  • 48V merchant network and server Power Supply Unit (PSU)

Block Diagram

Block Diagram - Texas Instruments INA791A Current Sense Amplifier

Application Diagram

Application Circuit Diagram - Texas Instruments INA791A Current Sense Amplifier

Perfornance Graph

Performance Graph - Texas Instruments INA791A Current Sense Amplifier
Published: 2025-11-30 | Updated: 2025-12-16