400kHz IMC-Hall® current sensor IC with dual overcurrent detection

The MLX91218 is a high-speed high-accuracy IMC-Hall® current sensor simplifying module designs with a dual OverCurrent Detection (OCD) functionality, a flexible supply 3.3V/5V and an improved SNR. With the IMC-Hall® technology - using a flexible U-shield for crosstalk immunity - currents can be measured in the ranges of 200A to 2000A.

The MLX91218 is a monolithic Hall-effect sensor based on the IMC-Hall® technology. The sensor provides an analog output voltage proportional to the applied magnetic flux density parallel to the IC surface.

The transfer characteristic of the MLX91218 is factory trimmed over temperature, and is programmable (offset, sensitivity, filtering, internal overcurrent threshold) during end-of-line customer calibration.

With its 400kHz bandwidth and fast response time, it is particularly adapted for high speed applications such as motor control, inverters and converters where fast response time, due to fast switching, is required.

Coming in a SOIC8 package, it includes a second OCD. To be noted that the on-chip overcurrent detection feature allows for board space and cost savings, by reporting an OCD event with active low open-drain output, that can be set within or outside the output linear sensing range.

In a typical current sensing application, the sensor is used in combination with a U-shaped shield which facilitates the mechanical assembly of the current sensor over traditional ferromagnetic cores. This shield is recommended to be laminated for high bandwidth applications. The MLX91218 can then be mounted over the bus bar and separated from it by the PCB. As the shield does not serve the primary purpose of concentration, it can be made smaller and lighter than ferromagnetic cores without losing signal thanks to the integrated magnetic concentrator (IMC). As a result, dense power electronics can be achieved enabling system savings and surface mount assembly.

The MLX91218 is compatible with the PTC-04 (DB-HALL05) for mass-production programming.

Application Examples

• Redundant monitoring of battery-management system (BMS)
• High Voltage Traction inverters (HV)
  • Phase current measurement
  • DC link current measurement
• 48V Boost-recuperation machines (48V)
  • Phase current measurement
  • DC link current measurement
• DCDC Converter
• Smart Battery Junction Boxes
• Smart Fuse Overcurrent Detection

XHF and VHF examples with standard shields

• MLX91218 AxV versions (Very high field): for current from 200 to 1200 A
• MLX91218 AxX versions (eXtra high field): for current from 200 to 2000 A