PIC18F23K20-E/MLQTP MICROCHIP [Microchip Technology], PIC18F23K20-E/MLQTP Datasheet - Page 300

• Manufacturer Part Number: PIC18F23K20-E/MLQTP
• Description: 28/40/44-Pin Flash Microcontrollers with 10-Bit A/D and nanoWatt Technology
• Manufacturer: MICROCHIP [Microchip Technology]

PIC18F2XK20/4XK20
23.2
For PIC18F2XK20/4XK20 devices, the WDT is driven
by the LFINTOSC source. When the WDT is enabled,
the clock source is also enabled. The nominal WDT
period is 4 ms and has the same stability as the LFIN-
TOSC oscillator.
The 4 ms period of the WDT is multiplied by a 16-bit
postscaler. Any output of the WDT postscaler is
selected by a multiplexer, controlled by bits in Configu-
ration Register 2H. Available periods range from 4 ms
to 131.072 seconds (2.18 minutes). The WDT and
postscaler are cleared when any of the following events
occur: a SLEEP or CLRWDT instruction is executed, the
IRCF bits of the OSCCON register are changed or a
clock failure has occurred.
FIGURE 23-1:
DS41303B-page 298
Change on IRCF bits
Note 1: The CLRWDT and SLEEP instructions
All Device Resets
LFINTOSC Source
2: Changing the setting of the IRCF bits of
3: When a CLRWDT instruction is executed,
WDTPS<3:0>
Watchdog Timer (WDT)
clear the WDT and postscaler counts
when executed.
the OSCCON register clears the WDT
and postscaler counts.
the postscaler count will be cleared.
SWDTEN
CLRWDT
WDTEN
Sleep
WDT BLOCK DIAGRAM
Enable WDT
WDT Counter
÷128
Advance Information
4
Programmable Postscaler
1:1 to 1:32,768
Reset
© 2007 Microchip Technology Inc.
WDT
Reset
Wake-up
from Power
Managed Modes