NXP Semiconductors MPC5566 - Chapter 23 V por Circuit

Voltage Regulator Controller (VRC) and POR Module
MPC5566 Microcontroller Reference Manual, Rev. 2
23-4 Freescale Semiconductor
Figure 23-2. Regions POR is Asserted
23.4.2.1 1.5 V POR Circuit
The 1.5 V POR circuit monitors the voltage on the V
RCSNS
pad. The 1.5 V POR functions if the V
RC33
pad is powered. If the user does not power V
RC33
to the specified voltage, the 1.5 V POR is disabled and
the user must follow the specified power sequence.
23.4.2.2 3.3 V POR Circuit
The 3.3 V POR circuit is used to ensure that V
DDSYN
is high enough that the FMPLL begins to operate
correctly.
23.4.2.3 RESET Power POR Circuit
The RESET power POR circuit monitors the supply that powers the RESET pin, and ensures that the
voltage supply to the RESET
pin is high enough to reliably propagate the state of the input. The supply
monitored by this POR cannot exceed 5.5 V.
23.5 Initialization and Application Information
23.5.1 Voltage Regulator Example
Figure 23-3 shows how to connect the VRC to the device.
POR negates
(Ramp up)
POR indeterminate POR asserts
(Ramp down)
POR indeterminate
POR asserts
Specified power supply range
Power supply