Can someone explain how this part of the circuit works? Why do they use PNP (
Q5), NPN (
Q3) transistors with inductor (
L1) and diode (
D1)? The Li-ion charger is a BQ2954.
The description for pin 14,
Current-switching control output
Pulse-width modulated push/pull output used to control the charging current to the battery. MOD switches high to enable current flow and low to inhibit current flow. (The maximum duty cycle is 80%.)
Thank you for help.