To ensure the safety and isolation of Class 3 high-voltage power supplies, such as 800V battery packs and electric vehicle chargers, two isolation barriers are required to reduce the risk to a low level. Until now, the MLX91220 and MLX91221 were only rated as basic (i.e., standalone) isolation devices, requiring engineers to incorporate additional elements, such as an isolation amplifier, into their designs.

With the new UL/IEC 62368-1 (material group I) certification, engineers can now use Melexis Hall effect sensors, knowing that their reinforced insulation is sufficient to protect the end user from the risk of high voltage without the need for additional insulation barriers. The new voltage ratings are (for pollution degree 2):

For the SOIC16 package: 1415V for basic insulation (BI) and 707V for reinforced insulation (RI).
For the SOIC8 package: 715V for basic insulation (BI) and 307V for reinforced insulation (RI).
Engineers currently using the MLX91220 or MLX91221 with an additional insulation barrier can now eliminate the unnecessary insulation components. Furthermore, for designs that currently only have basic insulation, it offers the possibility of requalifying as a reinforced insulated system without any changes to the Bill of Materials (BoM).

The introduction of this "upgrade," solely in the form of additional technical qualification, enhances the value of the already well-established Hall effect sensors by streamlining designs and reducing associated engineering efforts and costs. This solution not only maintains their highly accurate, flexible, and plug-and-play nature but also provides enhanced safety measures for a variety of applications, including on-board car chargers (OBCs), DC/DC converters, high-voltage chargers, renewable energy inverters, household appliances, and robotics.

"With the new MLX91220 and MLX91221 qualifications, we are providing engineers with the simplest route to enhanced insulation," says Bruno Boury, Product Line Manager at Melexis. "We have effectively improved 50 product variants at no cost to the customer, helping them meet critical safety requirements with a single component, thus alleviating production costs and packaging limitations."

The MLX91220 and MLX91221 sensors , with their proven reliability in industrial and automotive applications, further strengthen their market position thanks to this additional safety qualification. These current sensors are available in cost-effective, miniaturized, narrow-body SOIC8 packages with a 4 mm creepage distance and wide-body SOIC16 packages with an 8 mm creepage distance. Both devices feature a 300 kHz bandwidth, a short response time of 2 µs, and are available with a current range of 0–50 A RMS.