
PIC16F87X
DS30292C-page 164
2001 Microchip Technology Inc.
FIGURE 15-8:
RESET, WATCHDOG TIMER, OSCILLATOR START-UP TIMER AND POWER-UP
TIMER TIMING
FIGURE 15-9:
BROWN-OUT RESET TIMING
TABLE 15-3:
RESET, WATCHDOG TIMER, OSCILLATOR START-UP TIMER, POWER-UP TIMER,
AND BROWN-OUT RESET REQUIREMENTS
VDD
MCLR
Internal
POR
PWRT
Time-out
OSC
Time-out
Internal
Reset
Watchdog
Timer
Reset
33
32
30
31
34
I/O Pins
34
VDD
VBOR
35
Parameter
No.
Symbol
Characteristic
Min
Typ
Max
Units
Conditions
30
TmcL
MCLR Pulse Width (low)
2
——
sVDD = 5V, -40°C to +85°C
31*
Twdt
Watchdog Timer Time-out Period
(No Prescaler)
718
33
ms
VDD = 5V, -40°C to +85°C
32
Tost
Oscillation Start-up Timer Period
—
1024 TOSC
——
TOSC = OSC1 period
33*
Tpwrt
Power-up Timer Period
28
72
132
ms
VDD = 5V, -40°C to +85°C
34
TIOZ
I/O Hi-impedance from MCLR Low
or Watchdog Timer Reset
——
2.1
s
35
TBOR
Brown-out Reset pulse width
100
——
sVDD ≤ VBOR (D005)
*
These parameters are characterized but not tested.
Data in "Typ" column is at 5V, 25°C unless otherwise stated. These parameters are for design guidance only and are
not tested.