ISL94200

Description

The ISL94200 is an overcurrent protection device and analog front end for a microcontroller in a multi-cell Li-ion battery pack. The ISL94200 supports battery pack configurations consisting of 4-cells to 7-cells in series and 1 or more cells in parallel. The ISL94200 provides integral overcurrent protection circuitry, short circuit protection, an internal 3.3V voltage regulator, cell voltage monitor level shifters, and drive circuitry for external FET devices for control of pack charge and discharge. Selectable overcurrent and short circuit thresholds reside in internal RAM registers. An external microcontroller sets the thresholds by setting register values through an I2C serial interface. Internal registers also contain the detection delays for overcurrent and short circuit conditions. Using an internal analog multiplexer the ISL94200 provides monitoring of each cell voltage plus internal and external temperature by a separate microcontroller with an A/D converter. Software on this microcontroller implements all battery pack control functionality, except for overcurrent and short circuit shutdown.