PIC18F2331/2431/4331/4431 Data Sheet 28/40/44-Pin .
PIC18F4431 - 28/40/44-Pin Enhanced Flash Microcontrollers
PIC18F2331/2431/4331/4431 Data Sheet 28/40/44-Pin Enhanced Flash Microcontrollers with nanoWatt Technology, High-Performance PWM and A/D 2010 Micro.