i have designed a circuit based on 555 and transformer to give an output of 120Vac and 120mA with 500Hz frequency. the problem is in the current that I m getting only 8mA after the transformer. How can I amplify it to 120 mA? I m using a 12V Li battery as source and cannot use any bulky battery as my objective is to design a light weight device.
I quoted you a part of an article concerning amplification.
Transistors are devices that can amplify a signal in a circuit. If a signal in a circuit is too weak, it may not be enough to provide power to turn or or drive the load for a circuit. A transistor can provide amplfication from anywhere to up to 10,000% gain so that it can boost a signal in a circuit up to a desired level.
Say, we have a circuit in which we want to light an LED, but the current in the circuit is 40µA, too small to light an LED. If this is the current that we have flowing through the circuit, it's too small to do the desired task, which is to light the LED. However, if we place a transistor in the circuit, which has a gain of 100, the signal will be boosted from 40µA to 40x100=4mA. This current will now be sufficient to light our LED in the circuit. So transistor amplification has tremendous application when we need signal gain. http://goo.gl/ABVJkQ
I assume that you want the transformer to do power transfer from primary to secondary. The power you put in on the primary side equals the power you get out on the secondary side (neglecting losses, non linear behavior, and a slew of other considerations) Work out the power you need on the output side, whatever that is, the input side has to provide the same power plus 10-20 percent typically. Looking at your figures, a 12 volt battery is going to have to supply over an amp. What core are you using in the transformer, at 500Hz a mains transformer core will not work well.
