I gas u can, but if u wanna have a really good PWM controller u can pick an atmel AVR, f.e. ATmega8 and if u're not too noob in soldering it is quite easy to assemble an up to 16 channel 12-bit 1-2Khz PWM controller with RS232/COM PORT support. What about AVR core program I have done a PWM done so I can simply rewrite the code as needed an give u a HEX file ready for flashing into AVR CPU