Re: 2N3055 failure (power supply)


Phil Allison wrote:

<cbarn24050@xxxxxxx


I cant read this circuit very well, it appears to be an emmiter
follower. If thats the case then you have 2 basic problems. Firstly
your output is not inside the regulation loop so your regulation will
be poor. Secondly you have no short circuit protection, or indeed any
current control.


** Nonsense.

The OP supplied a partial schem and STATED that it was a current limited
supply.

Well i guess Phil, one of us cant read.


Both these problems are easily solved by looking at
the application notes for the 723.


** The OP very likely has a schem like figure 4 here:



http://www.national.com/ds/LM/LM723.pdf

Maybe but since he didnt state it its just speculation on your part.



Rsc is probably one of the 0.1 ohm ballast resistors shown in his schem,
resulting in a 6.5 amp limit per 3055 device.

That would be too bad if it was since the 2n3055 wont survive a short
at that current for long.





....... Phil

.

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