quick question about lm317s and lm337s:
say I want to have a + and - regulated supply. Would I need a center tapped transformer to use as the input to both of these, with the center as ground, and then rectify the + and - separately and send them into the chips? (lm337 handling the negative voltages, obviously, and lm317 handling positive)?
or, could i just have a transformer giving + and -, reference the - as ground, rectify, and use the lm317 with input being the + rail and the ADJ going to ground, and then use the ground rail as INPUT for the LM337 and connect the ADJ to +?
would the second option give a split setup, adjustable on both sides, one negative, one positive, referenced to a common ground?
There are schematics at the bottom.
Essentially, I have two questions: Will the first circuit work (I'm pretty sure it will), and, will the second work like I think it does, or did i screw something up with the references?
and yes, the schematics are not complete as far as hooking up the LM regulators, just imagine that the proper filtering caps and bypass diodes and such are there... just trying to get you guys a picture.
oh and the signal source would be a 30V or something transformed down from the 120V mains.
the reason for two rectifiers in the first circuit is to give both positive and negative full-wave rectification. they are hooked up in parallel, but oppositely. it makes sense to me that this would work, any reasons it wouldnt?
say I want to have a + and - regulated supply. Would I need a center tapped transformer to use as the input to both of these, with the center as ground, and then rectify the + and - separately and send them into the chips? (lm337 handling the negative voltages, obviously, and lm317 handling positive)?
or, could i just have a transformer giving + and -, reference the - as ground, rectify, and use the lm317 with input being the + rail and the ADJ going to ground, and then use the ground rail as INPUT for the LM337 and connect the ADJ to +?
would the second option give a split setup, adjustable on both sides, one negative, one positive, referenced to a common ground?
There are schematics at the bottom.
Essentially, I have two questions: Will the first circuit work (I'm pretty sure it will), and, will the second work like I think it does, or did i screw something up with the references?
and yes, the schematics are not complete as far as hooking up the LM regulators, just imagine that the proper filtering caps and bypass diodes and such are there... just trying to get you guys a picture.
oh and the signal source would be a 30V or something transformed down from the 120V mains.
the reason for two rectifiers in the first circuit is to give both positive and negative full-wave rectification. they are hooked up in parallel, but oppositely. it makes sense to me that this would work, any reasons it wouldnt?
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