Texas Instruments DRV421 Closed-Loop Current Sensing IC

Texas Instruments DRV421 Closed-Loop Current Sensing IC is designed for magnetic closed-loop current sensing solutions. This enables isolated, precise dc- and ac-current measurements. This provides both, a proprietary integrated fluxgate sensor, and the required analog signal conditioning, thus minimizing component count and cost. The low offset and drift of the fluxgate sensor, along with an optimized front-end circuit results in unrivaled measurement precision. This device provides all the necessary circuit blocks to drive the current-sensing feedback loop. The sensor front-end circuit is followed by a filter that can be configured to work with a wide range of magnetic cores. The integrated 250mA H-Bridge drives the compensation coil while doubling the current measurement range, compared to conventional single-ended drive methods. The device also provides a precision voltage reference and shunt sense amplifier. This allows the device to generate and drive the analog output signal.

Features

  • High-precision integrated fluxgate sensor
  • ±8µT max, ±5nT/°C typ offset and drift
  • Extended Current Measurement Range
    • ±250mA typ at 5V H-bridge output drive
  • Precision Shunt Sense Amplifier
    • ±75µV, ±2µV/°C offset and drift (max)
    • ±0.3%, ±5ppm/°C gain error and drift (max)
  • Precision Reference
    • ±2%, ±50ppm/°C accuracy and drift (max)
    • 2.5V or 1.65V pin-selectable voltage
    • VDD/2 selectable ratiometric mode
  • Magnetic core degaussing feature
  • Diagnostic features
    • Overrange and error flags
  • 3V to 5.5V supply voltage range
  • Fully specified over the extended industrial temperature range of –40°C to +125°C

Applications

  • Closed-loop DC- and AC-current sensor modules
  • Leakage current sensors
  • Industrial monitoring and control systems
  • Overcurrent detection
  • Frequency, voltage, and solar inverters

TI Reference Designs Library

TI Reference Designs - Texas Instruments DRV421 Closed-Loop Current Sensing IC
Publicado: 2015-10-01 | Actualizado: 2023-10-31