The attachment to my original message got lost it seems, so here it is.
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Final solution - Automatic turn off
The attachment to my original message got lost it seems, so here it is.
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In the past I tried with mosfets but the results were disapponting.Originally Posted by AMay
Then I used an PNP transistor much like Melanies post. I think that circuit as was presented by Melanie is the best up to this moment.
Ioannis
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on/off
Hi
Why not use a simple regulator with Enable pin ??? ( i.e LM 2941 ...)
Alain
Last edited by Acetronics2; - 6th February 2006 at 08:58.
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Why insist on using 32 Bits when you're not even able to deal with the first 8 ones ??? ehhhhhh ...
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IF there is the word "Problem" in your question ...
certainly the answer is " RTFM " or " RTFDataSheet " !!!
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Because at least 300uA is needed when in OFF state!
Still the previous circuit with an PNP like BC557 or BC856/7/8 is the #1.
Ioannis
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and, moreover saying "papa and mamma" ...
Ioannis,
this was an Example .... have a look to other brands too ( Micrel 29xxx ( 1µA ) ... etc, etc ).
Alain
************************************************** ***********************
Why insist on using 32 Bits when you're not even able to deal with the first 8 ones ??? ehhhhhh ...
************************************************** ***********************
IF there is the word "Problem" in your question ...
certainly the answer is " RTFM " or " RTFDataSheet " !!!
*****************************************
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Hi Alain. No offense :-)
300 uA or even 1uA might on some cases be too much. With the BC857 that I mentioned I could not measure the leakage current with the Fluke 179 multimeter (as voltage across a R).
Ioannis
P.S. On the real circuit, note that the PCB has to be cleared from solder because the leak may be more than the electronics in some cases!
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