PIC18F23K20_10 Datasheet, PDF (388/456 Pages) Microchip Technology – 28/40/44-Pin Flash Microcontrollers with nanoWatt XLP Technology

PIC18F2XK20/4XK20
FIGURE 26-7:
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 26-4 for load conditions.
30
31
34
34
FIGURE 26-8:
BROWN-OUT RESET TIMING
VDD
BVDD
35
VIVRST
Enable Internal
Reference Voltage
Internal Reference
Voltage Stable
36
VBGAP = 1.2V
TABLE 26-10: 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)
2
—
—
s
31
TWDT Watchdog Timer Time-out Period
(no postscaler)
3.5
4.1
4.7
ms 1:1 prescaler
32
TOST Oscillation Start-up Timer Period 1024 TOSC — 1024 TOSC — TOSC = OSC1 period
33
TPWRT Power-up Timer Period
54.8 64.4 74.1
ms
34
TIOZ I/O High-Impedance from MCLR
Low or Watchdog Timer Reset
—
2
—
s
35
TBOR Brown-out Reset Pulse Width
200
—
—
s VDD  BVDD (see D005)
36
TIVRST Internal Reference Voltage Stable
—
25
35
s
37
THLVD High/Low-Voltage Detect Pulse Width 200
—
—
s VDD  VHLVD
38
TCSD CPU Start-up Time
5
—
10
s
39
TIOBST Time for HF-INTOSC to Stabilize
—
0.25
1
ms
DS41303G-page 388
 2010 Microchip Technology Inc.