About "on time generator" of Constant on Time and Adaptive on Time control in the buck feedback

GARAM AN

Hello,

I could find the tech document.

I cannot find the different of COT and AOT

What is the difference between Constant on Time and Adaptive on Time control?

How are the "on time generator" of COT and AOT composed, and how they work with the output of loop compensation?

Thank you

0 Robert Taylor1 over 5 years ago

Hi Garam An,

The major difference between COT and AOT is the change with input/output voltages.

The COT maintains a constant on time regardless of input and output conditions and adjusts the off time to maintain output voltage regulation.

The AOT looks at the input voltage, output voltage and sets the on time accordingly to maintain a pseudo fixed frequency.

Hopefully this helps.

Thanks,

Robert

0 Bernd Geck over 5 years ago in reply to Robert Taylor1

Hello Garam,

as Robert mentioned the ON time is modulated by Vin to keep Fsw almost constant,

here is the video:

best regards, Bernd

Power management forum