Datasheet

ii
8284D–AVR–6/11
ATmega169A/PA/329A/PA/3290A/PA/649A/P/6490A/P
9.2Clock Sources .........................................................................................................31
9.3Default Clock Source ...............................................................................................31
9.4Calibrated Internal RC Oscillator .............................................................................32
9.5Crystal Oscillator .....................................................................................................32
9.6Low-frequency Crystal Oscillator .............................................................................34
9.7External Clock .........................................................................................................35
9.8Clock Output Buffer .................................................................................................36
9.9Timer/Counter Oscillator .........................................................................................37
9.10System Clock Prescaler ........................................................................................37
9.11Register Description ..............................................................................................38
10 Power Management and Sleep Modes ................................................. 40
10.1Overview ...............................................................................................................40
10.2Sleep Modes .........................................................................................................40
10.3BOD Disable
(1)
.......................................................................................................40
10.4Idle Mode ...............................................................................................................41
10.5ADC Noise Reduction Mode .................................................................................41
10.6Power-down Mode ................................................................................................41
10.7Power-save Mode .................................................................................................42
10.8Standby Mode .......................................................................................................42
10.9Power Reduction Register .....................................................................................42
10.10Minimizing Power Consumption ..........................................................................43
10.11Register Description ............................................................................................45
11 System Control and Reset .................................................................... 47
11.1Resetting the AVR .................................................................................................47
11.2Reset Sources .......................................................................................................47
11.3Internal Voltage Reference ....................................................................................51
11.4Watchdog Timer ....................................................................................................51
11.5Register Description ..............................................................................................53
12 Interrupts ................................................................................................ 56
12.1Overview ...............................................................................................................56
12.2Interrupt Vectors ....................................................................................................56
12.3Register Description ..............................................................................................60
13 External Interrupts ................................................................................. 61
13.1Overview ...............................................................................................................61
13.2Pin Change Interrupt Timing .................................................................................62