Other Parts Discussed in Thread: UCC21750, , UCC21710
We are using your UCC21750QDWEVM-025 evaluation board to determine the feasibility of the UCC21750 for our application and have some questions.
(1) Figure 14 in your SLUUBX2B user's guide shows the short circuit waveform. Why does it take 2.5us to turn-off when your datasheet indicates several hundred nanoseconds at worst case? The only difference I can see between the two cases is that the datasheet specifies a load of 100pF where as the evaluation board is 10nF.
(2) Our requirement is a turn-off time of less than 1.3us. How do we achieve this with the UCC21750? The desat capacitance in the evaluation board is 27pF (plus the capacitance of the Schottky and Zener diodes D8 and D7 respectively). How can we meet our requirements if the desat capacitance is already very low?
(3) I have conducted an experiment with the UCC21750QDWEVM-025 to replicate the waveform of Figure 14. I am observing similar turn-off times however, I am observing the desat threshold exceeding the 10V maximum specified in the datasheet. In fact, it appears to be over 11V. Are you able to comment on this?