
MC68HC08MR4/MC68HC908MR8 — Rev. 2.0
Technical Data
MOTOROLA
Power-On Reset (POR)
333
Technical Data — MC68HC08MR4/MC68HC908MR8
Section 19.
Power-On Reset (POR)
19.1 Contents
19.2 Introduction
This section describes the power-on reset (POR) module.
19.3 Functional Description
The POR module provides a known, stable signal to the MCU at
power-on. This signal tracks VDD until the MCU generates a feedback
signal to indicate that it is properly initialized. At this time, the POR drives
its output low. The POR is not a brown-out detector, low-voltage
detector, or glitch detector. VDD at the POR must go completely to 0 to
reset the MCU. To detect power-loss conditions, use a low-voltage
inhibit module (LVI) or other suitable circuit.