ISL88739B

The ISL88739B is a highly versatile battery charger configurable as a Hybrid Power Boost (HPB) charger, supporting 2-, 3-, or 4-cell batteries. The configuration allows the battery to work with the adapter to supply the system load when it exceeds the adapter capability, referred to as Turbo mode. The HPB charger configuration reverse-boosts battery energy to the system bus to help the adapter provide the system power in Turbo mode. The ISL88739B uses N-channel MOSFETs (NFETs) for all the switches to achieve the best performance and lowest BOM cost. The internal charge pump can turn on all the NFETs quickly or slowly, depending on the circumstance or the need. The ability to quickly turn on NFETs prevents system bus voltage drop when the battery is suddenly removed in Turbo mode or in Battery Learn mode. The ISL88739B provides many protection features including a PROCHOT# indicator for system low voltage, adapter overcurrent, battery overcurrent, or overheating, with an array of SMBus programmable parameters for maximum flexibility. The ISL88739B also features hardware-based adapter-current limit and battery-current limit in addition to SMBus programmable limits. The ISL88739B provides a high accuracy adapter current monitor, battery current monitor, and system power monitor outputs. Several configurable current-sense resistor value options provide maximum flexibility for working with high and low power systems, to achieve the best trade-off of current sensing accuracy vs power loss.