+/- Power Supply

AC to DC -/+ convertor . +/- PSU for use with power pack. Simple and easy to build. Good Luck!

Step 1:

Print this schematic for use .

Step 2: Parts

1X LM7815 POSITIVE VOLTAGE REGULATOR
1X LM7915 NEGATIVE VOLTAGE REGULATOR
2X 1000 MF CAPACITORS
4X 100 NF CAPACITORS
2X 470 MF CAPACITORS
2X 1N4001 DIODE

PROTOBOARD
WIRE
For LED
1X LED
1X 2K2 RESISTOR

Step 3: STEP1

AC PINS AND D1 AND D2
CONNECT D1 TO AC PIN 1 - CONNECT D2 TO AC PIN1 AND D2.

Step 4: STEP2

SOLDER C1 THEN C2 - NOTE THE POLARITY OF THE CAPACITORS
SOLDER THE NEG LEAD OF C1 TO THE POSITIVE LEAD OF C2 , SOLDER IT THEN TO AC PIN 2 - THIS IS NOW THE GND POINT .

Step 5: STEP 3

SOLDER IC1 AND IC2 THE POWER REGULATORS - NOTE THE PIN-OUTS
- THEN ADD C3 AND C4

Step 6: STEP4

NOW ADD THE REST OF THE CAPS C5 C6 C7 C8

Step 7: STEP 5

ADD THE LED - OPTIONAL BUT GOOD TO KNOW IF THE POWERS ON
ADD THE OUT PINS TOP- V+ ,MIDDLE GND , BOTTOM V-

Step 8: FINISH

WIRE PSU JACK TO THE AC PINS , WIRE +/- PINS OFF TO MODULE / DEVICE .
PLUG IN 15V POWER PACK . 500MA IS GOOD FOR UP TO 3 MODULES DEPENDING ON SIZE ANY MORE YOU WILL NEED A LARGER CURRENT , 1000MA FOR ANY MORE.

Comments

[charlessenf-gm]

Somewhat Off Topic. I am building a Power Supply that calls for 100nF caps and I can only find uF versions at the Shack. Is there an ONLINE guide that would allow me to "translate/convert" so I get the right caps the first time out? charlessenf AT yahoo com for anyone wanting to reply directly. Thanks.

[aa9gg]

0. 000 000 000 000 = 0. milli(m), micro(u), nano(n), pico(p)

therefore 100n = 0.1u

hope this helps others (just noticed the thread is 5 years old)

[microman171]

Don't know if this helps anymore...

100nF = 0.1uF.

It is a metric conversion from 100 nano to ? micro.

http://www.google.co.nz/search?hl=en&q=100+nanofarads+in+microfarads&btnG=Search&meta=&aq=f&oq=

Just type it into google =)

[Rob K]

Simple and easy to build. Good Luck!

Good encouragement there HAHA

Also to I'm not familiar with the LM7815, LM7915 what kind of voltage regulator are they dropping the voltage to. 5v 12v ?

[johnson_steve]

the 7815 is a standard +15v linear voltage regulator the 7915 is it's -15v counterpart

78' = +
79' = -

the last 2 digits are the voltage. these are common regulators that might even be available at radioshack (not the 79s) also commonly available: 7805, 7905, 7812 and 7912.

This looks like a good 15v bipolar supply for hobby projects. I hate to nitpick but I have to point out a few things.

1. This is a half wave voltage rectfier (the part that converts ac to dc) this isn't making the most of the power from your ac 'wall wart' for a few cents more you could add 2 more 1N4001 diodes. you could make a 'full wave' rectifier and use both ac lines from the transformer instead of just tying one to ground. this would also have the benefit of a more 'stable' ground for your dc circuit.

2. linear voltage regulators need about 2v (or so) of drop so if you want 15v out you want the transformer to be in the 18v to 35v range. the 15v ac transformer shown will not work. (a transformer marked 15v may not be 15v infact it's probably more so as always measure it yourself.)

3. on the drawing he clearly states: "for any more up to 10 use 1000ma or more." the 78 and 79 series regulators are only good up to 1amp (1000ma) and that's with a heat sink. I wouldn't try to pull more then 300ma through this circuit as shown.

[gozdee13]

Hello there. I was wondering how I would be able to do that with a bridge rectifier. Would all capacitors and resistors be the same? Is it just adding two more diodes?Necessarily 1N4001? I have this project to build, any help is very appreciated:( Thanks in advance.

[SomaticCircuits]

Thanks for pointing these out :-D It is a Half wave rectifier so it can be used with a wallwart Power pack insted of a transformer. Yes you do need a 2v of drop , but the powerpacks allways put out a lot more for that reason , inside commercial devices a 9v device will have a 7809 and a 9v powerpack , the powerpack will put out up to 12v from my experience. I use 2 of these designs in portable synth projects, each with 500ma, one unit has a VCF, ENV, VCA and a Peak Detector, the other a VCO VCF ENV VCA , both will no problems , for lager set ups I have used 1200ma through with no heating problems , although I recommend the use of a transformer based PSU designed especialy for modular synths, Blacet makes a fine example.

[LinuxH4x0r]

TURN OFF CAPSLOCK! ITS NOT COOL

[AngelLaHash]

but caps is easy to read when reading things quick i dont understand we class caps as shouting in typing i would of said bold was be like shouting its making it stand out to a point its saying look at me, in a thing like this the caps helps me to read it a lot easy without having the read the whole like. If id put this in caps you could of scaned in so quickly and seen what it is said. stupid little rules i think personaly (am i spose to put the I in a cap as its on its own or not now)

[SomaticCircuits]

Appoligies , I didnt know it offended you. :-(

[AsaBerdahl]

 How would I go about making it a dedicated 12v transformer. I've been experimenting with using a homemade transformer for my Car Power Amp Subwoofer project.

I know it will required the transformer, because I don't have a single walwart to repurpose.

How would I bring up the amperage and keep it at 12v. For that matter, it requires two 12v leads (one on the remote connect, and the power). Will the the supply maintain 12v if I bridge it between the two inputs that require it?

And I'm pretty sure this is a no-brainer, but it's going to need a power supply, isn't it?

Sorry to ask so many questions. I'm not usually this hyper.

[xiexie]

Is it safe to directly solder the LM7815 pins?
I used LM7805 to produce 5 Volt DC, but there is no voltage measured at the final output. I think this is because I soldered the LM7805 pins directly so that it got excessive heat from the solder. What do you guys think?
I used the schematic circuit below:

[Dipankar]

I am not able to follow your Instructable. Where is the circuit diagram? You may give lots of pictures but a circuit diagram is easy to follow. I hope you will add one to this. Another thing a circuit diagram needs no explanation.

[cam54321]

He has a hand drawn one as a pdf in step 1. Please go back and fix the caps lock.

[killerjackalope]

Excellent photos... Get rid of the caps lock, it does not make things more interesting, it just makes people look thick...