Part Number:TPS54560
We would like to use the TPS54560 for a buck-converter with an input voltage from 35-55 VDC. The TPS54560 switches very fast which generates spikes at the SW-pin when the internal FET switches off. Even with very careful layout and an RC-snubber across the freewheeling-diode, we measured spikes >10Vpk. This means that we cannot use the TPS54560, because the maximum voltage on the SW-pin is specified with 65V in the datasheet.
Questions:
At which voltage does the internal FET avalanche?
Is it allowed, that the SW-pin goes above 65V (e.g 70Vpk-spike due to leakage inductance) when the internal FET switches off?
If not, is there a way to slow down the switching speed of the internal FET?
Best regards
Christian