Datasheet

2002-2013 Microchip Technology Inc. DS30487D-page 179
PIC16F87/88
FIGURE 18-6: RESET, WATCHDOG TIMER, OSCILLATOR START-UP TIMER AND
POWER-UP TIMER TIMING
FIGURE 18-7: BROWN-OUT RESET TIMING
TABLE 18-5: RESET, WATCHDOG TIMER, OSCILLATOR START-UP TIMER, POWER-UP TIMER
AND BROWN-OUT RESET REQUIREMENTS
Parameter
No.
Sym Characteristic Min Typ† Max Units Conditions
30 TmcL MCLR
Pulse Width (Low) 2 sVDD = 5V, -40°C to +85°C
31* T
WDT Watchdog Timer Time-out Period
(16-bit prescaler = 0100 and no
postscaler)
13.6 16 18.4 ms VDD = 5V, -40°C to +85°C
32 T
OST Oscillation Start-up Timer Period 1024 TOSC ——TOSC = OSC1 period
33* T
PWRT Power-up Timer Period 61.2 72 82.8 ms VDD = 5V, -40°C to +85°C
34 T
IOZ I/O High-impedance from MCLR
Low or Watchdog Timer Reset
——2.1s
35 T
BOR 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.
VDD
MCLR
Internal
POR
PWRT
Time-out
Oscillator
Time-out
Internal
Reset
Watchdog
Timer
Reset
33
32
30
31
34
I/O Pins
34
Note: Refer to Figure 18-3 for load conditions.
VDD
VBOR
35