Yes we would really need to know the requirements for the AC you need. What is the AC voltage needed, how well regulated must it be? What amount of current (milliamps or amps) will you need to provide? What will the AC frequency be - and how steady must it stay? Typical house power in the USA is 120volts AC, and has a frequency of 60 hertz. If you are trying to take a automotive power source of 12 volts dc and make a few hundred watts of house power 120vac - then you can just buy an INVERTER at many auto supply stores - matching the wattage needed for your load.
If you have need of learning the specifics of how to do the conversion, it gets bit more to explain. Obviously we need to alternate the current on and off between x volts positive and x volts negative, and do it at the rate you need to make the frequency desired, but its not just on and off you will likely need. Turning it on and off between two supplies will give you a very square waveform, and most modern AC power is a sinewave that gently transforms from plus to minus in a curve. The needs of such a converter really do depend on the use of the power. Whether it needs to operate a light bulb (which could use DC as is) or run a motorized device that needs better waveforms and the ability to handle a stronger surge in current - how it will be used makes a big difference it what a design would use. An electric drill might show it needs for example 1 amp of power. At 120 volts this would be 120 watts of power - but at startup this same drill might require more current to get spinning, and could pull more when you really load it down. A conversion circuit to produce 120 watts of power would likely not handle a drill as well as a light bulb.
There are many ways to do the conversion - and most will not be very efficient - so if you need for example 120 watts of AC power - you will expend more on the input side. Back to the example - a 120 watt output is 1 amp at 120 volts - but that would be 10 amps at 12 volts if the circuit was lossless. Practical design would say you should figure on a significant loss in conversion, so it might be requiring 12 to 14 amps at 12 volts to run that 120w load.
Please let the forum know what DC power you intend to use, and what type of device needs the AC power and someone here will point you to a closer solution. Also - if you would, is this just to learn with or a real world application?
I hope this helps give you some more ideas. There are many new products on the electronic parts market that are designed to do power conversions.
Programmer1971 -
www.oldhackers.com