Help i need to convert 12v dc to 12v ac....

**Wildsupra** · 20-03-2011, 04:57 PM

most likely going to need hundreds of them. At this stage i need a few stright away to ge things moving.
so ideally need to work out to be a cheap easy way of doing it.
The h bridge is certainly a great option but im having difficulty finding the specs i need and i dont really know where to get them from. Ive already tried all the local places like jaycar, dick smith, tandy etc. With the h bridge ic i will also need to construct a little pcb board to hold the ic and any other component i may end up needing including possble heatsink and wires in and out. But thats fine.
Just need a starting point. Once i know the circuit works im more than happy to sit down and solder them all up. Just getting the first one sorted is the problem with my minimal electrical knowledge.

**Flex** · 20-03-2011, 06:12 PM

Does your LCD have a polarisation line?

**Wildsupra** · 20-03-2011, 09:22 PM

whats a polarisation line? lol

**RT40Corona4AGTE** · 20-03-2011, 09:41 PM

can you give some specs on the LCD please? model, manufacturer, etc ?

**Wildsupra** · 20-03-2011, 10:38 PM

I had it custom made so no manufacturer or model specs available.

I shall put it out there, would anyone like to build me a 12vac 400ua @ 32hertz power supply that runs off 12~14vdc (aka a car battery) im happy to pay for it and if its small and works a treat then i would be interested in buying many many more possibly in the hundreds. HIt me up via pm if you would like to help so we can discuss price etc.

Cheers
Matty

**o_man_ra23** · 22-03-2011, 09:26 AM

If it doesn't need to be a clean sine wave, 555 timer would be the most cost effective surely??

http://www.doctronics.co.uk/555.htm

You want to set it up as Astable. You want a 50% duty cycle.

NE555 timer chip (DIN size, not SMD) from Jaycar is $1.25 Add about 50c worth of resistors and capacitors, and you have the circuit.