PIC18F24J10-E/ML MICROCHIP [Microchip Technology], PIC18F24J10-E/ML Datasheet - Page 42

• Manufacturer Part Number: PIC18F24J10-E/ML
• Description: 28/40/44-Pin High-Performance RISC Microcontrollers with nanoWatt Technology
• Manufacturer: MICROCHIP [Microchip Technology]

PIC18F45J10 FAMILY
4.5
PIC18F45J10 family devices incorporate an on-chip
Power-up Timer (PWRT) to help regulate the Power-on
Reset process. The PWRT is always enabled. The
main function is to ensure that the device voltage is
stable before code is executed.
The Power-up Timer (PWRT) of the PIC18F45J10
family devices is an 11-bit counter which uses the
INTRC source as the clock input. This yields an
approximate time interval of 2048 x 32 μs = 65.6 ms.
While the PWRT is counting, the device is held in
Reset.
The power-up time delay depends on the INTRC clock
and will vary from chip to chip due to temperature and
process variation. See DC parameter 33 for details.
FIGURE 4-3:
FIGURE 4-4:
DS39682C-page 40
INTERNAL RESET
INTERNAL RESET
PWRT TIME-OUT
PWRT TIME-OUT
INTERNAL POR
INTERNAL POR
Power-up Timer (PWRT)
MCLR
MCLR
V
V
DD
DD
TIME-OUT SEQUENCE ON POWER-UP (MCLR TIED TO V
TIME-OUT SEQUENCE ON POWER-UP (MCLR NOT TIED TO V
Preliminary
T
PWRT
T
PWRT
4.5.1
If enabled, the PWRT time-out is invoked after the POR
pulse has cleared. The total time-out will vary based on
the status of the PWRT. Figure 4-3, Figure 4-4,
Figure 4-5
sequences on power-up with the Power-up Timer
enabled.
Since the time-outs occur from the POR pulse, if MCLR
is kept low long enough, the PWRT will expire. Bringing
MCLR
(Figure 4-5). This is useful for testing purposes, or to
synchronize more than one PIC18F device operating in
parallel.
high
TIME-OUT SEQUENCE
and
will
Figure 4-6
begin
© 2007 Microchip Technology Inc.
DD
, V
execution
DD
all
DD
RISE < T
): CASE 1
depict
immediately
PWRT
time-out
)