Other Parts Discussed in Thread: UCC21710, ISO7740
Tool/software:
Hello TI,
We're using the UCC27714 to drive an HBridge with a power transformer. I'm seeing a large spike due to the Miller capacitor when the high-side transistor conducts. I tried an active Miller clamp with a PNP, but it's not effective. I tried a second time by applying a negative voltage to the COM pin (relative to VSS). I don't see much current at 1 V on the power supply, but this is no longer the case when I increase the voltage beyond 3 V. Question: can this IC support this type of configuration (negative voltage on COM pin )? I see that the DC current could not be higher than 0.25A and the voltage across Vss-COM shall be below 7V. Other limitation? This will be for the prototype only (easy to do).
For the next generation, I see the UCC21710 reference, that has an external active clamp (the power w/ SIC transistor is seperated from the controller w/ an isolation - today the design put an iso7740 IC before).
Another reference that could best fit? (Valim=150 to 200V). A dual channel will be perfect.
Best regards,
