Inverters

Some of the favorite materials around ITP fall in the electroluminescent arena. There is electroluminescent paper or flat light, and el-wire. Both of these items require an inverter that transforms low voltage DC to high voltage AC. Another item that requires an inverter is the cold cathode fluorescent tube or CCFT.

This is an inverter with a pair of CCFTs

The inverters that we are interested in are DC to AC inverters. They take DC power and transform it into AC power

What's the difference between AC and DC?

• AC (Alternating Current) power switches rythmicaly to the tune of

60hz. First it flows in one direction and then in the other. This is what comes out of the wall and into all our electrical devices.

• DC (Direct Current) power moves in one direction. Most appliances

take AC but the AC is transformed into DC inside the device.

How does an inverter work?

The inverter takes in DC and passes it through a pair of power switching transistors and into a transformer.

By triggering the transistors in rapid succession, the power is fed to opposite sides of the transformer. This creates an alternating current. The transformer then steps up or steps down this alternating current to the voltage level required for the particular electroluminescent light source.

Most inverters for electroluminescent materials or CCFT take 12v DC and produce aprox 200V AC.