12dc to 12vac converter

Felino · Post by **Felino** » Fri Mar 14, 2008 2:32 am

I need a decive / need to build a device to convert 12vdc to 12vac, at around 6w.

Any suggestions?

(yes i have returned from the dead)

codeman · Post by **codeman** » Fri Mar 14, 2008 10:26 am

What do you need it for? Does it need to be a nice sine wave? Does it need to be centered around ground? An H-bridge is usually the way to go, but getting it to a nice sine wave can be pretty difficult.

Felino · Post by **Felino** » Fri Mar 14, 2008 5:31 pm

I doubt if it needs to be full sine wave, its for a tiny little pump i am using in a project.

THe pump drawns a maximum of around 400mah @ 12v.

Somthing i can build is nice.

EDIT: Is this site taking a hammering or somthing?

w00tLOL · Post by **w00tLOL** » Fri Mar 14, 2008 7:49 pm

i had to do something like that for my computers water cooling, but i found at the local electronics shop (jaycar in this case) a car adapter that did the trick, it was around 4 watts. and had a very messy square wave output (just wanted to test my new oscilloscope)

Felino · Post by **Felino** » Fri Mar 14, 2008 8:11 pm

Was this car adapter putting out 12vac from a dc source?

Link me!

codeman · Post by **codeman** » Sat Mar 15, 2008 6:50 pm

http://www.uoguelph.ca/~antoon/circ/555dcac.htm

would that work for you?

nitro2k01 · Post by **nitro2k01** » Sun Mar 16, 2008 5:36 am

Felino: What you should probably do is generate a squarewave, with a 555 or otherwise, and connect that to a transistor which controls the current. Preferably a FET with a low voltage dropout.
I don't have any schematics for it though, sorry.

Kurt_ · Post by **Kurt_** » Sun Mar 16, 2008 9:50 am

http://www.alibaba.com/catalog/11079937 ... owimg.html

eBay
Why not buy one?

Post by **marshallh** » Sun Mar 16, 2008 12:23 pm

Kurt_ wrote:http://www.alibaba.com/catalog/11079937 ... owimg.html

eBay
Why not buy one?

I used to think that reading was one of your worst skills. Now I know I'm right

codeman · Post by **codeman** » Sun Mar 16, 2008 2:39 pm

http://www.uoguelph.ca/~antoon/circ/555dcac.html

Ooops, try that one instead...forgot the L on the end...

timmeh87 · Post by **timmeh87** » Sun Mar 16, 2008 5:37 pm

You can low-pass filter a square wave to turn it into a sine wave

Felino · Post by **Felino** » Sun Mar 16, 2008 11:40 pm

Kurt wrote:Why not buy one?

Thats ac/ac

Thanks for the linky codeman i shall try that.

Thanks guys!