Datasheet

Table Of Contents
2010 Microchip Technology Inc. Preliminary DS39979A-page 409
PIC18F87J72 FAMILY
FIGURE 29-6: RESET, WATCHDOG TIMER, OSCILLATOR START-UP TIMER AND
POWER-UP TIMER TIMING
TABLE 29-11: RESET, WATCHDOG TIMER, OSCILLATOR START-UP TIMER, POWER-UP TIMER
AND BROWN-OUT RESET REQUIREMENTS
Param.
No.
Symbol Characteristic Min Typ Max Units Conditions
30 T
MCLMCLR Pulse Width (low) 2 TCY 10
T
CY
(Note 1)
31 T
WDT Watchdog Timer Time-out Period
(no postscaler)
3.4 4.0 4.6 ms
32 T
OST Oscillation Start-up Timer Period 1024 TOSC 1024 TOSC TOSC = OSC1 period
33 TPWRT Power-up Timer Period 45.8 65.5 85.2 ms
34 T
IOZ I/O High-Impedance from MCLR
Low or Watchdog Timer Reset
—2µs
38 T
CSD CPU Start-up Time 10 µs
200 µs Voltage Regulator
enabled and put to
sleep
39 TIOBST Time for INTOSC to Stabilize 1 µs
Note 1: To ensure device Reset, MCLR
must be low for at least 2 TCY or 400 s, whichever is lower.
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 29-3 for load conditions.