15.2 Reset Sources

The ATmega8A has four sources of Reset:

  • Power-on Reset. The MCU is reset when the supply voltage is below the Power-on Reset threshold (VPOT).
  • External Reset. The MCU is reset when a low level is present on the RESET pin for longer than the minimum pulse length.
  • Watchdog Reset. The MCU is reset when the Watchdog Timer period expires and the Watchdog is enabled.
  • Brown-out Reset. The MCU is reset when the supply voltage VCC is below the Brown-out Reset threshold (VBOT) and the Brown-out Detector is enabled.
Figure 15-1. Reset Logic