Re: power supply 2

On Mon, 17 Jul 2006 19:18:39 -0400, "Ken O" <lera@xxxxxxxxx> wrote:

HI,

I am working on a power supply. The transformer is getting hot after 30
minutes of use. I can touch it , but not more then a few seconds in a row. I
guess this is because of too much current.??

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So far, who knows?
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I use a 120v to 25v AC transformer, to a Bridge rectifier, then to a 2000uF
110 v capacitor .

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So the output of the supply, after the filter, will be about 35VDC
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This capacitor is then discharge through a transistor,
with a timer at 2% duty cycle to its base. The transistor too get very hot,
hotter then the tranformer.
The following is the rest of the circuit.
Should I be adding a resistor to decrease the current ?

---
Post the circuit.


--
John Fields
Professional Circuit Designer
.

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