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Anyone got any LM317/337 boards up for grabs?

Discussion in 'd.i.y.' started by James Evans, Jan 9, 2006.

  1. James Evans

    James Evans Bedroom Bodger

    Before I go off and buy all the parts and try to build suitable pcbs thought I'd see if anyone has any knocking about they'd be prepared to sell? I'm after 4 pcbs probably, though 2 would do as a starter.

    Also open to suggestions on alternative +ve/-ve regs? input will be +-14v - need to get it under +-13v to run my 8620 opamps under their max stress levels.



    ps, if anyone has a list of R values and most suitable caps (not oscons I gather for the output...) would be greatly appreciated
  2. hacker

    hacker Delicious and nutritious

    I don't have any boards, but have a few LM317T regs you're welcome to. Not new, but in perfect condition. As for caps, tants are recommended in the datasheet which you can view here: http://www.national.com/ds.cgi/LM/LM117.pdf (ignore the fact it's for the LM117, it's also the sheet for the 317).

    The formula for calculating the correct resistor values are also in the datasheet.

    Edit: alternatively, you could take the easy option and use L7812CV and L7912VC regulators (+ and - versions, respectively). They're probably a bit more noisy, but will give you a fixed 12v output without the hassle of figuring out resistors, etc.

    If price/time wasn't an option, I'd go the whole hog and build some of Andy's super regs - the 317 / 7x12 regs can't even come close to that kind of performance.

    Hope that helps.

  3. James Evans

    James Evans Bedroom Bodger

    thanks for the input Carl. Price is a restraint at the moment, plus there's no regulation at the moment so I want to see what effect a cheap 317/337 setup gives me to start with. I may investigate the fixed regs you mention - is a 14v input enough headroom to get the 12v out?
  4. hacker

    hacker Delicious and nutritious

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