what is the best way to get a vref in HV process?

Can you give some suggestion ? thanks in advance.
the suppy voltage is a big wide.

How many amp ? Look for current source or voltage source based on mosfet.

thanks Sec.
amp have only 3, if care about driver capibility , a buffer may be added

i have a 50amp 148volt dc mosfet motor drive circuit that i needed to do this with.

if you dont need much current, what i did:
a voltage divider, just two resistors , to give your voltage.... with the highest resistance possible while providing amps you need,
then a zener or tvs across to catch anything nasty... then a very low resistance, large capacitor across, and another tiny ceramic across.

i was tapping not only HV, but a high power square wave with some nasty spikes in it.
your application may need much less filtering... or you may need more amps of low voltage

the less resistence, the larger, lower resistence caps you need.


if your HV isnt as nasty as mine, and you need <500ma low voltage, just use a voltage divider, then a voltage regulator, lm7808 lm7812 etc. also use a lm317 as a current regulator if you need(if the resistors are low enough ohms to let enough current go thru to burn up)..

5 components. 3 resistors, lm78xx, lm317 ...