the input is 36Vdc and it is very high power(500W) and the output current of -12VDC is 1AThere is a wide variety of switching regulators that will do it.
What is the current capacity of the power source?
Thanks so much.Hello,
Perhaps the attached PDF might give you some ideas.
Bertus
my input is positive not negative , so u can not use it7912 ? That would be the easiest method..
How much of that 13.9A is being used?the input is 36Vdc and it is very high power(500W) and the output current of -12VDC is 1A
for another circuitsHow much of that 13.9A is being used?
Do you have 1+A to spare for the negative converter?for another circuits
yes, forget all the issues about the source, you have vin=36vdc and what ever current do you needDo you have 1+A to spare for the negative converter?
Had to ask because an unbelievable number of people think they can get something for nothing...yes, forget all the issues about the source, you have vin=36vdc and what ever current do you need
Is it possible to use 7812 and reverse connections? Output from 7812 to be used as 0V and the ground to be used as -12V? Similar to measuring positive voltage with multimeter leads reversed..my input is positive not negative , so u can not use it
Not if the positive source power supply is referenced to 0V.Is it possible to use 7812 and reverse connections? Output from 7812 to be used as 0V and the ground to be used as -12V? Similar to measuring positive voltage with multimeter leads reversed..
http://www.seekic.com/uploadfile/ic-circuit/20097935338680.gifNot if the positive source power supply is referenced to 0V.
The circuit you refer to works because the positive 12V regulator is galvanically isolated from the power source through a transformer.http://www.seekic.com/uploadfile/ic-circuit/20097935338680.gif
//For some reason, i cannot upload this file//
My input also is positive DC , so I can use this circuithttp://www.seekic.com/uploadfile/ic-circuit/20097935338680.gif
//For some reason, i cannot upload this file//
**Edit: I mean no offense to Mr Chips, I'm just making sure I demonstrate what i was saying **
You mean buck boost converter and for the oscillator you have to use transformer and this a lotNot if the positive source power supply is referenced to 0V.
@karas One solution is to use a buck converter to supply the -12V directly.
Another solution is to build an oscillator, rectify and convert to about -15VDC and then use a 7912 three-terminal regulator.
No. Sketch it out, keeping in mind that there is no energy storage in a linear regulator. What pushes the ground pin down to -12 V? Also, with the input at +36 V, that'w 48 V between the regulator's input and GND pins, way outside it's spec.Is it possible to use 7812 and reverse connections? Output from 7812 to be used as 0V and the ground to be used as -12V? .