This post explains for the PMIC.
The Part Number is RK818.
The function of this semiconductor is High Performance PMIC.
The package is 7mm x 7mm, QFN 68 Pin type.
Manufacturer: Fuzhou Rockchip Electronics
Preview images :
This is Power management integrated circuit.
The RK818 is a high performance PMIC for multi-core processor applications that require multiple outputs in a single-cell Li-Ion battery (including lithium and lithium polymers), providing a complete power solution and a simple external application.
The device integrates a synchronous buck DC-DC converter that charges the battery while supplying power to the system load. USB can be used as this IC power input, the input current limit can be set to 450mA or 820mA to meet the USB2.0 and USB3.0 requirements, the maximum can be set to 3A to meet the high current charging USB applications. Charge management includes input current limiting, trickle charge, constant current / constant voltage charging, charge termination, charge overtime security protection and other functions. All the specific values of these functions can be easily set via the I2C interface.
1. Switch mode Li-ion battery charger providing charging current up to 3A.
2. Power path controller with 5A current path.
3. Accurate battery fuel gauge.
4. Real time clock（RTC）
5. Low standby current of less than 40uA (at 32KHz clock frequency)
6. Fast transient response due to the current mode architecture
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