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σ25 and σ26 dual rail supply +/- 92 VDC

PostPosted: November 5th, 2019, 1:11 pm
by Rinman77
Hi,
I want a regulated dual rail supply at +/- 92VDC. Is it possible to add a Zener diode to the base of the σ78/σ79 in order to up the control voltage?
Thanks,
Ron

Re: σ25 and σ26 dual rail supply +/- 92 VDC

PostPosted: November 5th, 2019, 11:19 pm
by amb
No, that is not advisable. The voltage regulator chips were not designed to be used in this way.

P.S. I deleted your other post in the σ78/σ79 subforum because the question there is redundant to this one.

Re: σ25 and σ26 dual rail supply +/- 92 VDC

PostPosted: November 6th, 2019, 9:57 am
by Rinman77
Thanks for the response.
Are there then any options for regulation of higher voltage rails?
Ron

Re: σ25 and σ26 dual rail supply +/- 92 VDC

PostPosted: November 6th, 2019, 12:04 pm
by amb
Without doing a parametric search I am not aware of any monolithic IC voltage regulators that could handle that much voltage. You'll probably need to implement a discrete voltage regulator circuit using high voltage parts. Something like a high voltage version of σ22, but it's not trivial to do.

Re: σ25 and σ26 dual rail supply +/- 92 VDC

PostPosted: November 7th, 2019, 3:36 am
by amb
What application is this for anyway? Power amplifier?