On-time Generator Circuit and Switching Converter

An on-time generator circuit, applied to a switching converter, wherein the switching converter comprises a main power transistor, and the on-time generator circuit comprises:

• a ramp module configured to generate a ramp signal based on a drive signal of the main power transistor and an input voltage of the switching converter;
• a compensation module configured to generate a compensation signal based on the input voltage of the switching converter and a duty cycle of the switching converter;
• and
• a timing signal generation module configured to generate a timing signal based on the ramp signal, the compensation signal, and an output feedback signal, wherein the timing signal represents turn-on time (Ton) of the main power transistor, and the output feedback signal represents an output of the switching converter;
• wherein
• the compensation signal is configured to offset delay time generated by the timing signal to keep a switching frequency of the main power transistor constant at different duty cycles.