SN8P2711 unlock technology
The SN8P2711 is a high-performance and low-power system with RISC-1ike. It is very cheap and has relatively few pins. It widely uses in small appliances, temperature measurement, high-end intelligent chargers, switching power supplies and other fields. This design uses SN8P27llA microcontroller as the control system of portable power.
The control circuit mainly completes functions such as collecting voltage, controlling charging and discharging working state, and power indication. Switch s1 enables the entire system to be opened and closed. Four LEDs are used to indicate the amount of charge in the charge and discharge state — controls whether the boost circuit is output to the load. P4.1 connect to the switch control terminal ON/OFF1 of the booster chip S8355, and the control chip starts or stops the boosting operation. P4.2 port to collect output voltage. The received sampling voltage is AD-converted to detect whether the output load voltage is standard. The P4.3 and P4.4 ports collect the polymer battery voltage and current signals, and the received sampling voltage is AD-converted. Check if the output load voltage is standard. The P0.0 port first detects whether there is an input voltage from the outside, and then controls whether the charging circuit works. The P0.4 port use as a signal indicating that the battery is fully charged. When the polymer battery fully charges, the STDBY port of the AP5056 outputs a low-level message, which is sent to the P0.4 port for detection, detects a low level and controls the P0.0 port output. Low level, so that the AP5056 is in a sleep state and stops charging. Because the MCU is powered by internal polymer battery, the voltage is unstable during charging and discharging. To ensure the stable power supply of the MCU, the Xc62063 low-dropout high-current regulator used for voltage regulation.