UCC28C44: What is the minimum controllable on-time for this device?

Hi Kurt Schmidt,

You will notice from the datasheet that the minimum ON pulse width is about 35ns (tD) set by the delay of the CS comparator and gate drive.

To the best of my knowledge this is the only limitation imposed by the controller itself.

If you operate the part in current control mode you will find that you need to filter or blank the current sense signal before connecting it to the CS pin. This is needed otherwise the part will terminate the pulse early due to the current spike that occurs when charging the MOSFET gate and discharging the Drain node capacitance.

In practice the filtering or blanking needed extract this turn-on current spike will define your minimum controllable pulse width and hence duty cycle.

I hope this answers your question.

Thanks

Joe Leisten