The dynamic power path management (DPPM) of the BQ25120A will separate the charging current from system current. When you have a valid IN source, current is shared at the PMID between charging the battery and providing system load. The device internal loops (VINDPM, DPPM) will monitor and control the input voltage and current constantly to detect faults and take any needed action to support both charging and the load at PMID, SYS, and LS/LDO. The following summarizes both modes, for a more detail explanation refer to the datasheet.
Input Voltage Based Dynamic Power Management (VINDPM): If the input source is not able to support the charging current and system load once the VIN approaches the set VINDPM threshold, the input current will be reduced to prevent further drop of the supply.
Dynamic Power Path Management Mode (DPPM): With a valid input source the input current is shared between charging the battery and powering the systems loads. If the sum of systems and charging current exceeds the VIN capabilities the VINDPM loop will reduce the PMID current, which will drop the PMID voltage. if the PMID voltage drops below the DPPM threshold, the charging current will be reduced to stabilize PMID. If PMID continue to drop even without charge current, the device will enter supplement mode.
The dynamic power path management (DPPM) can improve the battery charging performance by avoiding system crashes and maximizing the power available from the adapter.