Hello,
Two LM5017 have failed so far. It doesn't always happens but when it does part of the IC burn out. The Vin is around 60V and the output is 12V. That 12V is used to power some 5V IC and MOSFET gate drivers for a SIX phase motor controller. I had monitored the 12V current consumption and I got an average value of about 25 mA. I know that there are some pick current when the MOSFET gate is driven (about 1.2 A since I use a 10 ohm resistor between the driver and the gate). But I use very well sized low size and bootstrap capacitors for each drivers so I think the MOSFET gate peak current shouldn't be an issue.
I think the problem could be related to the big size capacitors on the 12V side and the LM5017 start-up. Actually I use a 10 uF bootstrap capacitor and a 100 uF low side capacitor (maybe quite too large) for every of the six drivers and two 22 uF capacitors on the LM5017 Vout side.
I am thinking about adding the soft start feature to the LM5017 design. Could that be the solution to the problem?
Many thanks in advance.
Best Regards.