网页6 2486AA–AVR–02/2013 ATmega8(L) AV CC AV CC is the supply voltage pin for the A/D Converter, Port C (3..0), and ADC (7..6). It should be externally connected to V CC, even if the ADC is not used.If the ADC is used, it should be con-nected to V CC through a low-pass filter. Note that Port C (5..4) use digital supply voltage, V CC. AREF AREF is the analog reference pin for the A/D Converter.