Patent ID: 9158315
Filing Date: 2015-10-13
Classification: G05F,H02M

Abstract:
1. A constant on time (COT) mode power supply, comprising: a feedback circuit detecting an output voltage of the COT mode power supply to generate a feedback signal; a compensator connected to the feedback circuit, and generating an error signal responsive to a difference between the feedback signal and a reference value; a ramp generator providing a ramp signal; a comparator connected to the compensator and the ramp generator, and comparing the error signal with the ramp signal to generate a comparison signal; an on time generator connected to the comparator, and triggering a first constant on time responsive to the comparison signal for regulating the output voltage; and a load transient improving circuit connected to the comparator, detecting a load condition based on the ramp signal, the error signal and the comparison signal, and generating a second constant on time for regulating the output voltage when the output voltage is drooped due to a load variation, to thereby prevent the output voltage from undershooting.