Freescale Semiconductor MC68HC908MR32 - Manual (Page 113)

MC68HC908MR32 • MC68HC908MR16 Data Sheet, Rev. 6.1
Freescale Semiconductor 113
Chapter 11
Power-On Reset (POR)
11.1 Introduction
This section describes the power-on reset (POR) module.
11.2 Functional Description
The POR module provides a known, stable signal to the microcontroller unit (MCU) at power-on. This
signal tracks V
DD
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. V
DD
at the POR must go
completely to 0 to reset the microcontroller unit (MCU). To detect power-loss conditions, use a low-voltage
inhibit module (LVI) or other suitable circuit.