How to increase Overvoltage shutdown limit In TOP271 JX in stackfet configuration

Posted by: Kanwar on 01/06/2017

Hello Pi-Team

I am under process of designing a buck-boost converter with a Stack FET [SIC FET + SIC DIODE pure CCM operation with large dual stack Sendust inductor] configuration along with TOP 271 JX as low side switch. My lowest input voltage would be 50VAC and highest would be 500VAC covering the industrial 3 phase range by sufficient margin. The datasheet gives value of RLS as 4M Ohm for terminating the operation of the switch at OV threshold of 451VDC. Is there any way to increase the threshold of OV to say 600VDC ??

Regards

Kanwar

Comments

Did I asked something which went over the head of PI-Neela?

in order to rising OV point, you need to apply soft zener clamp to the V pin resistor string. example can be found in DER447 design report page 14.

https://ac-dc.power.com/design-support/reference-designs/design-examples/der-447-184-w-llc-cv-cc-power-supply/

Thanks Pi-Blue , appreciated