Re: using mosfets as rectifiers?

From: El Meda (gomerem_at_hotmail.com)
Date: 06/11/04 

Date: Fri, 11 Jun 2004 08:55:01 -0500

Albert <pass@pass.com> wrote:

>With a bipolar transistor acting as a switch, I am probably limited
>severely by the transformer step up ratio. But, the mosfet needs very
>little real power applied to the gate to make it switch, so looking
>for a higher turns ratio audio type transformer might be the answer as
>well.

You can use the same transformer that you already have, and use two
schottky diodes and two capacitors to make a voltage duplicator, then
apply that voltage to the gate of the mosfet:

                                           |
                                        ||-+
                                        ||<-
                                o-----o-||-+
                                - | |
                                ^ | |
                         || | | |
                        -||-----o | |
                         || - --- |
                                ^ --- |
        From transformer | | |
                        --------o-----o----o

created by Andy´s ASCII-Circuit v1.24.140803 Beta www.tech-chat.de 

---
El Meda.
http://ingemeda.tripod.com/

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