Message:18992 In: TECH.WW
From: G8MNYDate: Tue, 17 Mar 26 07:37:00 Z
Newsgroups: TECH.WW
Subject: Splitting a floating PSU
Message-ID: <54664_GB7CIP>
Path: N2NOV|VE2PKT|VE3CGR|PI8ZTM|CX2SA|GB7CIP
R:260317/0744z @:N2NOV.#RICH.NY.USA.NOAM $:54664_GB7CIP
R:260317/0743Z 64225@VE2PKT.#TRV.QC.CAN.NOAM LinBPQ6.0.25
R:260317/0743Z 71634@VE3CGR.#SCON.ON.CAN.NOAM LinBPQ6.0.25
R:260317/0742Z @:PI8ZTM.#ZH1.NLD.EURO #:52030 [Den Haag] $:54664_GB7CIP
R:260317/0742Z @:CX2SA.SAL.URY.SOAM #:62923 [Salto] FBB7.00e $:54664_GB7CIP
R:260317/0737Z @:GB7CIP.#32.GBR.EURO #:54664 [Caterham Surrey GBR]
From: G8MNY@GB7CIP.#32.GBR.EURO
To : TECH@WW
By G8MNY (New Aug 06)
(8 Bit ASCII graphics use code page 437 or 850, Terminal Font)
Here is a simple way to spit a single floating power supply into +/- rails. It
can be for any voltage 6V-100V to give ñ3V to ñ50V.
ÚÄÄÄÄÄÄÄÄ¿ +
³ ÃÄÄÄÄÂÄÄÄÄÂÄÄÄ>+ve
³Floating³ 1K ³/
³ ³ ÃÄÄ´NPN
³ Power ³ _³_ ³\e
³ ³ D1\_/ ÃÄÄÄ>0V
³ Supply ³ ³ ³/e
³ ³ ÃÄÄ´PNP
³ ³ 1K ³\
³ ÃÄÄÄÄÁÄÄÄÄÁÄÄÄ>-ve
ÀÄÄÄÄÄÄÄÄÙ -
The asymmetrical currents & voltages will affect the components needed (e.g.
transistors have to handle peak offset current & heat), in some applications,
e.g. value of 1K R may be 39K on 100V. Higher currents may need darlingtons or
P & N ch MOSFETs.
The above circuit should provide adequate balance for testing most things that
need a balanced supply.
D1 provides some cross over bias keeping the transistors in class B, 2 diodes
in series may do better, but easy to get into class AB/A & get hot when this is
not needed!
Y Don't U send an interesting bul?
73 de John G8MNY @ GB7CIP
Return To Bulletin List