I have a non-audio application which could use a low leakage diode.
I was just googling this subject when I came across a discussion of using BJT's B-C junction for a low leakage diodes. The examples were all small devices though. I need a little bigger current handling as well.
Would this tip work just as well with a TO-220 BJT? Something anybody has in their parts box, say a TIP-41? How about anything else in the part box, like a MOSFET, etc.?
I was just googling this subject when I came across a discussion of using BJT's B-C junction for a low leakage diodes. The examples were all small devices though. I need a little bigger current handling as well.
Would this tip work just as well with a TO-220 BJT? Something anybody has in their parts box, say a TIP-41? How about anything else in the part box, like a MOSFET, etc.?
1A forward current with 10mA reverse leakage seems to be easy to attain with pretty much any competent diode currently available. A basic 1N4004 will handle 1A forward current and has a max. leakage spec at 100ºC of 50µA, and a typical 100ºC spec of 1µA. I don't know how hot "hot" is in your world, but these specs at 100ºC are pretty nice, and are a lot better if you can run cooler. You could pore through a lot of data sheets and maybe optimize this, but a gumball diode should be able to easily beat this spec.
I don't have an exact spec because the lower the leakage the better the circuit performs, but let's say 1A forward current and 10mA leakage (hot) would be great.
+1 to what Monte said. Are you so used to using schottkys that you forget regular silicon diodes are low leakage compared to schottkys?
That is ¨**ludicrous** performance, as shown above a plain old 1N4004 is some 200 times better, go figure.10mA leakage (hot) would be great.
Even germanium OA- series could probably fit the bill, but out of curiosity, I measured a single sample: a BD201 from Philips, because I am completely sure about its origin, and at 60V Vcb and 27°C (present temperature here), the leakage current is 30nA. Not super-low, but worth considering, especially taking into account that it is just a single randomly selected type. By screening more types, you could probably find much better candidatesI don't have an exact spec because the lower the leakage the better the circuit performs, but let's say 1A forward current and 10mA leakage (hot) would be great.
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