Output PWM resolution more than 12 bit possible?

hey, i want to input 10V at analog input pins of duemilanove. Is it possible? since max input voltage is only 5V. And are there any boards available to provide more than 12 bit resolution in output PWM?? Plz guide me in my both queries. :-X :-?

I don’t know what to say about the 12 bit resolution in output PWM, but you can use two 100K ohm resistors to create a voltage divider and in your program multiply the input by 2.

And are there any boards available to provide more than 12 bit resolution in output PWM?

There is only 8 bits resolution available for PWM on the Arduino. Using a TLC5940 gives you 12 bits PWM. However, I am not aware of any other system giving you more resolution than this. Why would you want this? If it is for an analogue output then you are much much better off using an external D/A.