AVR-Chat

hi all 
well this is my first time to programing micro controller so i will use 
proteus program to be sure first that the program will be in  a right 
way to make simulation so i want your help if u don't mind plz  . i use 
proteus before but how can i use it with micro . i don't have till now 
a good idea . i want to make control on the speed of fan this fan will 
decrease the temperature in a small box but i have a question in my 
circuit i will use temperature sensor i think that its output will be 
sure voltage so i will put voltage source to the input of the micro or 
do we have the ability to use the sensor in the proteus   
thank u for reading my e_mail . i wait for ur replay  .BYE