The BQ24078RGTT is a linear Li-Ion battery charger for single-cell packs, drawing power from a USB port. It terminates at 4.35 V and delivers up to 1.5 A charge current. The device integrates over-temperature, over-voltage, reverse-current, and short-circuit fault protection, which reduces the external component count for a safety-compliant charger circuit. Charge current and safety timer are programmable via external resistors, so one BOM can cover multiple cell capacities without firmware changes.
Supply voltage and input interface
Maximum supply voltage is 6.4 V, which gives headroom above the nominal 5 V USB bus and allows the charger to operate from a 5.5 V regulated rail without an external LDO. The USB interface designation means the part handles the input current negotiation and power-path management typical of USB-charged devices.