RT9422A Datasheet | Richtek

Description The RT9422A Li-Ion/Li-Polymer battery fuel gauge is a microcontroller peripheral that provides fuel gauging for single-cell battery packs. The RT9422A resides within the battery pack and manages a non-removable battery or removable battery pack. The RT9422A reports State Of Charge, State Of Health, Full Charge Capacity, Time To Empty and Cycle Count based on the Voltaic Gauge with Current Sensing (VGCS) algorithm by using the voltage difference between battery voltage and OCV to calculate the increasing or decreasing SOC, with current sensing pensation to report battery SOC. Voltaic Gauge with Current Sensing algorithm can support smoothly SOC and does not accumulate error with time and current. That is an advantage pared to coulomb counter which suffer from SOC drift caused by current sense error and battery self-discharge. The RT9422A provides plete battery status monitor with interrupt alarm function. It could alert to host processor actively when condition of battery over/under-voltage and over-temperature in charging/over-temperature in discharging. Especially for high C-rate battery charging application, it can measure battery voltage by kelvin sense connection to eliminate the IR drop effect for optimal charging profile and safety. More useful alarm functions are Under SOC alert and SOC Change. The secondary safety features of the RT9422A can be used to indicate more serious faults via the SAFE pin. This pin can be used to blow an in-line fuse to permanently disable the battery pack from charging or discharging. The SAFE pin also can used to detect secondary protection IC status and log battery status in the NVM when protection be triggered. To prevent battery pack cloning, the RT9422A integrates SHA-1/HMAC authentication with a 128-bit secret key. Features - Support Pack Side Fuel Gauging - Battery Fuel Gauge for 1-Series (1s Xp) Li-Ion/Li-Polymer Applications - State of Charge (SOC) Calculated by Voltaic Gauge TM with Current Sensing (VGCS) - No...