Adaptive ramp time modulation

A controller for a power converter, comprising:

• a drive circuit configured to generate a drive signal to control switching of a power switch to a control a transfer of energy from an input-side of the power converter to an output-side of the power converter in response to a request signal including request events representative of an output of the power converter, wherein the drive circuit is configured to turn on the power switch in response to the request events in the request signal;
• and
• an adaptive current limit generator configured to generate a current limit signal in response to the drive signal and the request signal, wherein the drive circuit is configured to turn off the power switch when a current sense signal representative of a current through the power switch reaches the current limit signal, wherein the adaptive current limit generator further comprises:
• an upper threshold generator configured to generate an upper threshold of a current limit range of the current limit signal in response to a comparison between a switching frequency of the power switch and a frequency threshold,
• a ramp generator coupled to the upper threshold generator, wherein the ramp generator is configured to generate the current limit signal that increases and then decreases within the current limit range in response to the power switch turning OFF.

A controller for a power converter, comprising:

• a drive circuit configured to generate a drive signal to control switching of a power switch to a control a transfer of energy from an input-side of the power converter to an output-side of the power converter in response to a request signal including request events representative of an output of the power converter, wherein the drive circuit is configured to turn on the power switch in response to the request events in the request signal;
• and
• an adaptive current limit generator configured to generate a current limit signal in response to the drive signal and the request signal, wherein the drive circuit is configured to turn off the power switch when a current sense signal representative of a current through the power switch reaches the current limit signal, wherein the adaptive current limit generator further comprises:
• an upper threshold generator configured to generate an upper threshold of a current limit range of the current limit signal in response to a comparison between a switching frequency of the power switch and a frequency threshold, wherein the upper threshold generator comprises:
• an amplifier stage configured to compare a switching frequency of the power switch and a frequency threshold to generate an output, wherein the output of the amplifier stage is configured to vary in response to a difference between the switching frequency of the power switch and the frequency threshold;
• and
• an integrator configured to generate the upper threshold of the current limit range of the current limit signal in response to the output of the amplifier stage and the request signal.