| 主权项 |
1. A switched-mode power supply (SMPS) controlling circuit for controlling an output voltage of a main circuit of a SMPS, the SMPS controlling circuit comprising:
a switching status selecting unit configured to generate a switching status selecting signal according to a voltage feedback signal reflecting a voltage change of the main circuit; a reference voltage generating unit connected with the switching status selecting unit, and configured to output a reference voltage according to a voltage output status selected from a plurality of voltage output statuses according to the switching status selecting signal; a first comparator connected with the reference voltage generating unit, and configured to output a pulse width modulation (PWM) controlling signal according to the reference voltage, and according to a current feedback signal that reflects a current change of the main circuit; a pulse frequency modulation (PFM) controlling unit connected with the switching status selecting unit, and configured to output a PFM controlling signal with a frequency according to a frequency output status selected from a plurality of frequency output statuses according to the switching status selecting signal; a logic unit connected with the first comparator and the PFM controlling unit, and configured to output a switching controlling signal according to the PWM controlling signal and the PFM controlling signal; and a driving unit connected with the logic unit, and configured to control a power switch of the main circuit to switch on or switch off to thereby stabilize the output voltage of the main circuit according to the switching controlling signal.
|
