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Power management module tips

time2006/05/19

After the default configuration is started, the phone will generate a BBWAKEUP signal to return to the PMIC to confirm, and then successfully boot, so you need to keep PWRKEY in the pressed state to know that the BBWAKEUP signal is received.
一.Three wake-ups can turn on the phone or wake up the system
1. Press PWRKEY, the phone starts the boot process. After the default configuration is started, the phone will generate a BBWAKEUP signal to return to the PMIC to confirm, and then successfully boot, so you need to keep PWRKEY in the pressed state to know that the BBWAKEUP signal is received. 
2.The RTC module will generate a BBWAKEUP signal to wake up the system. For example, if rtc alarm is set, after the system enters the sleep state and the alarm time arrives, rtc generates BBWAKUP to wake up the system and enter the alarm operation.
3. Plugging in the charger will wake up the system.

二. The normal voltage status of the mobile phone.
1. UVLO:
If the battery voltage is lower than 3.2v, the phone is turned off and enters the UVLO mode. In this mode, the RTC module works normally.
2. DDLO
If the battery voltage is lower than 2.5v, the phone enters DDLO mode and the rtc module stops working.

三. In charging mode
1. If the chip's charging detector detects that the charger input voltage is higher than 7V or lower than 4.3V, the charging will be removed and charging will stop.
2. The chip charge controller can control the charging mode:
(1) Pre-charge mode (battery voltage is less than 3.2v, the phone is off).
(2) Fast charging mode, also called constant current charging mode (battery voltage between 3.2v and 4.2v).
(3) Constant voltage mode (after the battery voltage reaches 4.2V).
3. Charger charging process:
(1) First plug in the charger to determine whether the battery voltage has reached 2.2v. If not, wait for 5 minutes, then judge, if the battery voltage exceeds 2.2v, go to the next step. If not, then charge off, prove the charger. has a problem.
(2) Continue to judge whether the battery has exceeded 4.3v. If it is exceeded, the controller will disconnect the charger.
(3) If the charger is not disconnected, continue to judge whether the battery voltage exceeds 3.3v. If it is lower than 3.3v, enter Precc (precharge mode). After 35 minutes, judge whether the voltage is lower than 3.3v. Below 3.3V, the charger is turned off (if it has not been used for 35 minutes, it proves that there is a problem with the battery). If it is greater than 3.3v, it will enter the fast charging mode.
(4) After entering the fast charging mode, it is determined whether the battery voltage is greater than 4.1v, and the direct current is greater than 4.1v, and enters the constant voltage charging mode.
(5) In the constant voltage charging mode, it is determined whether the battery voltage has reached 4.2v until it reaches 4.2v, and then gradually reduces the charging current until it is less than the minimum chargeable current.
(6) Then disconnect the charger and stop charging. If the charger is not removed, the cycle determines that the battery voltage is less than 4.05v, and then re-enters the fast charging mode.