How to reduce VIPER17 start-up voltage (from the default 100 Vdc to 50 Vdc)

[emontllo]

Posted on August 23, 2013 at 11:08

Hello,

I would like to operate a flyback converter at a wide rectified voltage range (from 50 Vdc to 380 Vdc).

Is there any way to reduce the Flyback start-up voltage of a VIPER? Although the Brown out protection can be deactivated and the flyback can effectively work at 50VDC rectified voltage (I have test it and it does work properly), it is not possible to start the driver at low voltage.

Any recommendation, external power-up circuit suggestion would be greatly appreciated.

Ernest

#viper #viper17 #brown-out

[emontllo]

Posted on August 26, 2013 at 15:51

I have tried to supply the Vdd externally but it still does not start. I guess there is no other way than providing > 80 V to the drain. I will need to find another flyback controller - switch...