Multi-Cell Li-Ion ICs Offer Comprehensive Protection Features

Willich-Münchheide, Germany: Rohm Semiconductor’s new family of low-consumption, current protector ICs employ multiple-cell series-connected Li-ion battery packs (up to 13 cells). The ML5207, ML5208, ML5235, and ML5237 battery-management ICs detect the overcharge or overdischarge and overcurrent of each cell. They also integrate the gate driver for automatic On/Off control of the external PMOS-FET or N-channel FET for charge and discharge. The ICs will likely find homes in applications such as power tools.

Also part of the new family is the ML5218 Li-ion battery-management IC for hybrid-electric and electric vehicles. It handles packs of four to 14 cells and features a high-accuracy voltage measurement function to detect overcharge/overdischarge, passive cell balancing, and the possibility of four temperature measurements with externally connected sensors. In addition, the IC includes several self-diagnosis functions that are activated and analysed by an external MCU. In this way, it’s possible to detect open and short cell connections, as well as communication errors between the MCU and the IC.

Because it uses a high-voltage process, ML5218 is able to withstand a maximum input voltage of over 80V. If more than 14 cells are required, up to 32 ICs can be controlled via a multistage connection. As a result, support is available for up to 448 cells.

www.rohm.com/eu