Isolated Integrated Hall-Effect Current Sensors for Power Conversion Applications Lower Than 50A RMS

Melexis has introduced two new isolated integrated Hall-effect current sensors, the MLX91220 (5 V) and MLX91221 (3.3 V) for automotive and industrial applications such as on-board chargers (OBC), DC/DC converters, power supplies, and small electric drives. The 300 kHz bandwidth makes them suitable for power conversion applications lower than 50A RMS. By integrating sensing elements and high accuracy signal conditioning with voltage isolation, the MLX91220/21 delivers a response time of just 2µs in a miniature SOIC8 narrow body and SOIC16 wide-body packages.

The MLX91220 improves the dual on-chip overcurrent detection (OCD) function for enabling essential dual on-chip overcurrent detection (OCD) function. The MLC91220/21 uses an internal differential sensing concept instead of the ferromagnetic concentrators for detecting the magnetic field generated by the integrated primary conductor. This differential concept provides a high level of stray field immunity and enables higher density power electronics, as the sensor is less affected by stray magnetic fields in close proximity.

The SOIC8 package is rated to 2.4 kVrms isolation as per IEC/UL-62368, and the SOIC16 wide body package doubles this to 4.8 kV rated isolation. The high pin count and increased conductor thickness of the SOIC16 package provides a lower primary conductor resistance. The lower resistivity of 0.75mohm (SOIC16) and 0.85mohm (SOIC8) helps us to differentiate the devices from discrete shunt solutions. Sample and development kits of the MLC91220/21 are available for purchase from the company website and local representatives.

Features of the MLC91220/21 Isolated Integrated Current Sensors

• Factory trimmed AC and DC current sensor
• Analog ratiometric or fixed output voltage
• Combining sensing element, signal conditioning & isolation in a miniature surface mount package
• High-speed sensing: DC to 300 kHz bandwidth; 2μs response time
• Robust against external magnetic fields
• Low ohmic losses of integrated conductor: 0.9mΩ SOIC-8;0.75mΩ SOIC-16

Note: More technical information can be found in the datasheets of MLX91220 and MLX91221 linked at the bottom of this page and on the MLX91220 isolated integrated sensor and MLX91221 isolated integrated hall current sensor product page.