PIC18F2331_07 Datasheet, PDF (359/400 Pages) Microchip Technology – 28/40/44-Pin Enhanced Flash Microcontrollers with nanoWatt Technology, High Performance PWM and A/D

PIC18F2331/2431/4331/4431
FIGURE 25-7:
RESET, WATCHDOG TIMER, OSCILLATOR START-UP TIMER AND POWER-UP
TIMER TIMING
VDD
MCLR
Internal
POR
PWRT
Time-out
Oscillator
Time-out
Internal
Reset
Watchdog
Timer Reset
33
32
I/O Pins
Note: Refer to Figure 25-4 for load conditions.
30
34
31
34
FIGURE 25-8:
BROWN-OUT RESET TIMING
VDD
VIRVST
Enable Internal
Reference Voltage
Internal Reference
Voltage Stable
BVDD
35
36
VBGAP = 1.2V
TABLE 25-8: 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
TmcL MCLR Pulse Width (low)
31
TWDT Watchdog Timer Time-out Period
(no postscaler)
32
TOST Oscillation Start-up Timer Period
33
TPWRT Power-up Timer Period
34
TIOZ I/O High-impedance from MCLR
Low or Watchdog Timer Reset
35
TBOR Brown-out Reset Pulse Width
36
TIVRST Time for Internal Reference
Voltage to become Stable
37
TLVD Low-Voltage Detect Pulse Width
Legend: TBD = To Be Determined
2
—
—
—
4.00 TBD
1024 TOSC — 1024 TOSC
—
65.5 TBD
—
2
—
200
—
—
—
20
50
200
—
—
μs
ms
— TOSC = OSC1 period
ms
μs
μs VDD ≤ BVDD (see D005)
μs
μs VDD ≤ VLVD
© 2007 Microchip Technology Inc.
Preliminary
DS39616C-page 357