Hi all,
Been a while… I've been scooting around doing my usual "too many hobbys" trick; but still have been working on my weird gadget I was discussing earlier in the year… I'm now at the point where I've modeled a good working prototype in LTspice; but I'm missing a lot of the peripherals.
I have a few possibly basic questions regarding power supplies AND stuff to do with DC voltage sources for other parts of my circuit…
Power Supplies:
I've designed up a lot of variants of my schem, and have found superior performance (in sim) when using some comparators that run on a different V source (significant enough to consider them strongly for use in a prototype).
So most of my circuit runs on 15V; but the comparators want around 3V. Even if this changes, it's got me thinking about "what is the best way to generate a dual power supply"...
Is the best solution here to use a power transformer with dual output options to get a separate 15V and a separate 3V? The stupid part of my question is: can I just burn off 12V from the 15V supplies; or is this just, as mentioned, stupid?! i.e. inefficient or dodgy?! If I went, say 500 series, could I still consider 3V supplies (as the Xfmr situation is less attractive here)...
I've searched around, but can't find any discussion specific to what I'm wondering (which might imply that it's not good practice to burn up the 12V!!)...
DC Questions:
Within my circuit I'll be using a few steady DC sources. Similar to above, just wondering what good practice is here, as these will be typically around or less than 1V…
So if I DID use a 15V supply, would I rectify this, and then burn off 14V somewhere? seems inefficient! Would this burn amps; or do I just scale up resistors to be low current (I'm still getting a little confused here, as I read that high ohm is effectively low current, but can't quite understand how you can drop voltage through a divider without wasting electrons?!).
OR is there another way that I can syphon off 1V efficiently...
What's best practices here?
-----
As always, I really appreciate any help here - sorry if this is 101 basics again! I've searched around, but can't get any solid advice on the do's and don'ts…
Jonny
Been a while… I've been scooting around doing my usual "too many hobbys" trick; but still have been working on my weird gadget I was discussing earlier in the year… I'm now at the point where I've modeled a good working prototype in LTspice; but I'm missing a lot of the peripherals.
I have a few possibly basic questions regarding power supplies AND stuff to do with DC voltage sources for other parts of my circuit…
Power Supplies:
I've designed up a lot of variants of my schem, and have found superior performance (in sim) when using some comparators that run on a different V source (significant enough to consider them strongly for use in a prototype).
So most of my circuit runs on 15V; but the comparators want around 3V. Even if this changes, it's got me thinking about "what is the best way to generate a dual power supply"...
Is the best solution here to use a power transformer with dual output options to get a separate 15V and a separate 3V? The stupid part of my question is: can I just burn off 12V from the 15V supplies; or is this just, as mentioned, stupid?! i.e. inefficient or dodgy?! If I went, say 500 series, could I still consider 3V supplies (as the Xfmr situation is less attractive here)...
I've searched around, but can't find any discussion specific to what I'm wondering (which might imply that it's not good practice to burn up the 12V!!)...
DC Questions:
Within my circuit I'll be using a few steady DC sources. Similar to above, just wondering what good practice is here, as these will be typically around or less than 1V…
So if I DID use a 15V supply, would I rectify this, and then burn off 14V somewhere? seems inefficient! Would this burn amps; or do I just scale up resistors to be low current (I'm still getting a little confused here, as I read that high ohm is effectively low current, but can't quite understand how you can drop voltage through a divider without wasting electrons?!).
OR is there another way that I can syphon off 1V efficiently...
What's best practices here?
-----
As always, I really appreciate any help here - sorry if this is 101 basics again! I've searched around, but can't get any solid advice on the do's and don'ts…
Jonny