PIC16F872_06 Datasheet, PDF (131/168 Pages) Microchip Technology – 28-Pin, 8-Bit CMOS Flash Microcontroller with 10-Bit A/D

PIC16F872
FIGURE 14-6:
RESET, WATCHDOG TIMER, OSCILLATOR START-UP TIMER AND
POWER-UP TIMER TIMING
VDD
MCLR
Internal
POR
PWRT
Time-out
OSC
Time-out
Internal
Reset
Watchdog
Timer
Reset
33
32
I/O Pins
Note: Refer to Figure 14-3 for load conditions.
30
31
34
34
FIGURE 14-7:
BROWN-OUT RESET TIMING
VDD
VBOR
35
TABLE 14-3: RESET, WATCHDOG TIMER, OSCILLATOR START-UP TIMER, POWER-UP TIMER,
AND BROWN-OUT RESET REQUIREMENTS
Parameter
No.
Symbol
Characteristic
Min
Typ†
Max Units
Conditions
30
TMCL MCLR Pulse Width (Low)
2
—
—
μs VDD = 5V, -40°C to +85°C
31*
TWDT Watchdog Timer Time-out Period
7
(No Prescaler)
18
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 —
—
2.1
μs
or Watchdog Timer Reset
35
TBOR Brown-out Reset Pulse Width
100
—
—
μs VDD ≤ 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.
© 2006 Microchip Technology Inc.
DS30221C-page 129