12V variable speed motor control?

[mister_e]

i would sggest you to change your PIC and use a flash version that have a PWM module in like 16F88, 16F628 and how many other Usually i use PIC16C711 on my pin board.

BUT it's not impossible. Depending of your programming skill you could use internal timer interrupt to produce you PWM. A bit tricky but not impossible. i still prefer the use of internal PWM... make everything soooooooooo simple and keep my few last hairs on my head.

Yes a 25 mA PIC i/o can drive a MOSFET. But for safety sake and for high current driving, i would prefer to use opto-isolator between the PIC and the MOSFET.

some cheap opto-isolator PS-2501-1

some MOSFET that spring to mind now IRFZ44N, IRFZ48R, HUF75339P3.

[droptail]

So to be clear, I cannot simply use PWM command of PIC BASIC PRO with 16C711? (I have 16C711 chips already). What if I use external RC as see in PBP manual? Still no PWM control? My programming skills don't include timer interrupt experience.

I have researched the MOSFET's and have found that FP30N06LE MOSFET N-CH LOG 60V 30A TO-220AB can be directly driven by logic level. I am going to put a simple resistor network to assure MOSFET remains off upon power-up. It also restricts the PIC output to a safe level. Still need an OptoIso?