The LP7820B is a fully integrated TWS charging case solution with MCU, charger, boost and load switches. The LP7820B has built-in an 8-bit MCU core with up to 32K-byte flash and 1K-byte RAM. A low on-resistance BUS-FET is integrated to manage the input power from the VIN pin. A bidirectional buck or boost converter is integrated to manage charging and discharging of the battery. The buck charger supports up to 1A charging current with up to 95% efficiency. The ultra-low quiescent current boost converter consumes less than 2μA quiescent current and supports up to 0.6A output current. Two independent load switches feature earphone insert detection, removal detection and provide power from the PMID pin to the VOL pin and VOR pin with ultra-low voltage drop. An NTC circuit is offered to manage the temperature range that charging or discharging is allowed. The LP7820B offers power path management that allows the system to be powered up with a fully-discharged battery. It can dynamically manage the power from the VIN input and the battery to meet the system loading needs.
Multiple features are offered for the safe operation of the system, including input voltage OVP (over voltage protection), UVLO (under voltage lockout), OTP (over temperature protection), SCP (short circuit protection), etc. When powered by a battery, LP7820B can operate with only 8µA current.
The whole System is in a 28-pin 4 X 4 QFN package.