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Help with power supply?

5/1/1999 12:38 PM
FuzzyFruit	Help with power supply? I'm getting ready to build a couple distortion circuits that use -16 and +16 voltages on the power pins of the 741 IC. My question is: How can I use a normal 12 volt AC or DC adapter to provide me with +12 and -12 volts DC? Can I use 2 zener diodes (1n5353?) and a couple 470uf caps in the circuit below to give me my power? 12 volts in ---------------- + 12 ~p~ ~p~ - -- ^ / ~p~ ~p~ GROUND----------------- GROUND ~p~ ~p~ - -- ^ / ~p~ ~p~ ----------------- - 12 (???) Any help would be very much appreciated!

5/1/1999 12:38 PM

FuzzyFruit

Help with power supply?

I'm getting ready to build a couple distortion circuits that use -16 and +16 voltages on the power pins of the 741 IC. My question is:

How can I use a normal 12 volt AC or DC adapter to provide me with +12 and -12 volts DC?

Can I use 2 zener diodes (1n5353?) and a couple 470uf caps in the circuit below to give me my power?

12 volts in ---------------- + 12
 
                 ~p~    ~p~
 
                 -    --
 
                 ^    /
 
                 ~p~    ~p~
 
       GROUND----------------- GROUND
 
                 ~p~    ~p~
 
                 -    --
 
                 ^    /
 
                 ~p~    ~p~
 
            ----------------- - 12 (???)

Any help would be very much appreciated!

5/1/1999 1:38 PM
R.G.	You'll have to use a half wave rectifier for each polarity. Hook one side of the AC adapter to ground, the other to the junction of two diodes, one cathode and one anode. The free anode connects to the (-) end of a capacitor to ground, the free cathode connects to the (+) end of a capacitor to ground. The capacitor voltages will be 12* 1.414 Volts DC. Use big caps (1000's of uF) if you have any current draw at all or ripple will be bad.

5/1/1999 1:38 PM

R.G.

You'll have to use a half wave rectifier for each polarity.

Hook one side of the AC adapter to ground, the other to the junction of two diodes, one cathode and one anode. The free anode connects to the (-) end of a capacitor to ground, the free cathode connects to the (+) end of a capacitor to ground. The capacitor voltages will be 12* 1.414 Volts DC. Use big caps (1000's of uF) if you have any current draw at all or ripple will be bad.

5/1/1999 1:43 PM
FuzzyFruit	Thanks RG,... I will try that,.....your help is invaluble! Jeff

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