SI9730

Si9730 Vishay Siliconix Dual-Cell Lithium Ion Battery Control IC FEATURES D D D D D D Over-Charge Protection Over-Discharge Protection Short Circuit Current Limiting Battery Open-Circuit Center Tap Protection Cell Voltage Balancing Undervoltage Lockout D D D D D D Individual Cell Voltage Monitoring Low Operating Current (30 mA) and Shutdown Current (1 mA) Internal N-Channel MOSFET Driver High Noise Immunity Accurate ("1.19%) Over-Charge Voltage Detection Four Different Cell Types Covered DESCRIPTION The Si9730 monitors the charging and discharging of dual-cell lithium-ion battery packs (carbon or coke chemistry) ensuring that battery capacity is fully utilized while ensuring safe operation. The Si9730 provides protection against overcharge, over-discharge, and short circuit conditions which are hazardous to the battery and the environment. Battery voltages of each individual cell are monitored at the center-tap connection by an internal A/D converter through the VC pin. If one or both of the cells is determined to be overcharged, an internal cell balancing network “bleeds” off current at 15 mA until both cells are charged to the same maximum level. Depending on the condition of each cell, the Si9730 will switch two external source-connected n-channel MOSFETs on or off to allow the cells to be charged or to provide current to the load. The Si9730 is available in an 8-pin SOIC package with an operating temperature range of −25 to 85°C. The Si9730 is available in both standard...