Datasheet

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8025M–AVR–6/11
ATmega48P/88P/168P
9.6Calibrated Internal RC Oscillator .............................................................................34
9.7128 kHz Internal Oscillator ......................................................................................35
9.8External Clock .........................................................................................................35
9.9Clock Output Buffer .................................................................................................36
9.10Timer/Counter Oscillator .......................................................................................36
9.11System Clock Prescaler ........................................................................................36
9.12Register Description ..............................................................................................38
10 Power Management and Sleep Modes ................................................. 40
10.1Sleep Modes .........................................................................................................40
10.2BOD Disable ..........................................................................................................41
10.3Idle Mode ...............................................................................................................41
10.4ADC Noise Reduction Mode .................................................................................41
10.5Power-down Mode ................................................................................................42
10.6Power-save Mode .................................................................................................42
10.7Standby Mode .......................................................................................................42
10.8Extended Standby Mode .......................................................................................42
10.9Power Reduction Register .....................................................................................43
10.10Minimizing Power Consumption ..........................................................................43
10.11Register Description ............................................................................................45
11 System Control and Reset .................................................................... 47
11.1Resetting the AVR .................................................................................................47
11.2Reset Sources .......................................................................................................47
11.3Power-on Reset .....................................................................................................48
11.4External Reset .......................................................................................................49
11.5Brown-out Detection ..............................................................................................49
11.6Watchdog System Reset .......................................................................................50
11.7Internal Voltage Reference ....................................................................................50
11.8Watchdog Timer ....................................................................................................51
11.9Register Description ..............................................................................................55
12 Interrupts ................................................................................................ 58
12.1Interrupt Vectors in ATmega48P ...........................................................................58
12.2Interrupt Vectors in ATmega88P ...........................................................................60
12.3Interrupt Vectors in ATmega168P .........................................................................63
12.4Register Description ..............................................................................................66
13 External Interrupts ................................................................................. 68