Multi-phase battery charging with boost bypass

A charging system for a portable electronic device, comprising:

• a switching converter comprising a plurality of inductors;
• and
• a control circuit configured to use the switching converter to convert a battery voltage into a set of output voltages to simultaneously power a low-voltage subsystem and a high-voltage subsystem in the portable electronic device, wherein the control circuit is further configured to:
• during discharge of a battery in a low-voltage state, power the low-voltage subsystem from the battery voltage along a first bypass path through the charging system that bypasses the plurality of inductors and power the high-voltage subsystem by up-converting the battery voltage using the plurality of inductors;
• and
• during discharge of the battery in a state above the low-voltage state, power the low-voltage subsystem from the battery voltage along the first bypass path and power the high-voltage subsystem from the battery voltage along a second bypass path that bypasses the plurality of inductors.

A portable electronic device, comprising:

• a first set of components in a high-voltage subsystem;
• a second set of components in a low-voltage subsystem;
• a battery having a battery voltage;
• a switching converter comprising a plurality of inductors;
• and
• a control circuit configured to use the switching converter to convert the battery voltage into a set of output voltages to simultaneously power the low-voltage subsystem and the high-voltage subsystem, wherein the control circuit is further configured to:
• during discharge of the battery in a low-voltage state, power the low-voltage subsystem from the battery voltage along a first bypass path through the switching converter that bypasses the plurality of inductors and power the high-voltage subsystem by up-converting the battery voltage using the plurality of inductors;
• and
• during discharge of the battery voltage in a state above the low-voltage state, power the low-voltage subsystem from the battery voltage along the first bypass path and power the high-voltage subsystem from the battery voltage along a second bypass path through the switching converter that bypasses the plurality of inductors.