RT9451
Description
The RT9451 integrates a high efficiency USB friendly switch mode charger with On-The-Go (OTG) support for single cell Li-ion and Li-polymer batteries, D+D- detection, and a 50m A LDO regulator into a single chip.
The charger features a synchronous 375k Hz PWM controller with integrated power MOSFETs, input current sensing and regulation, Minimum Input Voltage Regulation (MIVR), high accuracy charge current and voltage regulation, and charge termination. It charges the battery in three phases : low current pre-charge, constant current fast charge, and constant voltage trickle charge. The input current is automatically limited to the value set by the host. The charger can be configured to terminate charge based on user-selectable minimum current level and automatically restart the charge cycle if the battery voltage falls below the recharge threshold. A safety timer with reset control provides a safety backup for I2C interface. The charger automatically enters sleep mode or...
