SPST Switch Popping

Started by dpresley58, September 18, 2009, 10:41:04 AM

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anchovie

But the way that diagram's drawn, if you make V1 and V2 the same source then you will be connecting + and - together!
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dpresley58

...which is something I'm not wanting to do, I'm guessing.

I started looking through the datasheets for various JFETs after completely toasting a J201 by hitting it with the full 9v on the gate. A wisp of light grey smoke and "that smell" rewarded the approach...

From what I gather, even though they're a normally-open device, I still need to spec a part that allows enough current through the source-drain junction and can handle more than 9v on the gate. Is this correct? If it is, a J111 is looking like a good candidate. I'm thinking a voltage divider to feed the gate will also provide a path to ground in order to bleed off residual capacitance within the JFET.

Runnin' blind here, so input is appreciated.
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