PIC18LF2420-I/SP Microchip Technology, PIC18LF2420-I/SP Datasheet - Page 260

• Manufacturer Part Number: PIC18LF2420-I/SP
• Description: IC MCU FLASH 8KX16 28-DIP
• Manufacturer: Microchip Technology
• Series: PIC® 18Fr

Specifications of PIC18LF2420-I/SP

• Core Size: 8-Bit
• Program Memory Size: 16KB (8K x 16)
• Core Processor: PIC
• Speed: 40MHz
• Connectivity: I²C, SPI, UART/USART
• Peripherals: Brown-out Detect/Reset, HLVD, POR, PWM, WDT
• Number Of I /o: 25
• Program Memory Type: FLASH
• Eeprom Size: 256 x 8
• Ram Size: 768 x 8
• Voltage - Supply (vcc/vdd): 2 V ~ 5.5 V
• Data Converters: A/D 10x10b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 28-DIP (0.300", 7.62mm)
• Controller Family/series: PIC18
• No. Of I/o's: 25
• Eeprom Memory Size: 256Byte
• Ram Memory Size: 768Byte
• Cpu Speed: 40MHz
• No. Of Timers: 4
• Package: 28SPDIP
• Device Core: PIC
• Family Name: PIC18
• Maximum Speed: 40 MHz
• Operating Supply Voltage: 2.5|3.3|5 V
• Data Bus Width: 8 Bit
• Number Of Programmable I/os: 25
• Interface Type: I2C/SPI/USART
• On-chip Adc: 10-chx10-bit
• Number Of Timers: 4
• Core: PIC
• Processor Series: PIC18LF
• Maximum Clock Frequency: 40 MHz
• Data Ram Size: 768 B
• Data Rom Size: 256 B
• Mounting Style: Through Hole
• Height: 3.3 mm
• Length: 34.67 mm
• Maximum Operating Temperature: + 85 C
• Minimum Operating Temperature: - 40 C
• Supply Voltage (max): 5.5 V
• Supply Voltage (min): 2 V
• Width: 7.24 mm
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant, Lead free / RoHS Compliant

PIC18F2420/2520/4420/4520
23.2
For PIC18F2420/2520/4420/4520 devices, the WDT is
driven by the INTRC 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
INTRC 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 (OSCCON<6:4>) are changed or a clock
failure has occurred.
FIGURE 23-1:
DS39631E-page 258
Change on IRCF bits
All Device Resets
INTRC Source
WDTPS<3:0>
Watchdog Timer (WDT)
SWDTEN
CLRWDT
WDTEN
Sleep
WDT BLOCK DIAGRAM
Enable WDT
WDT Counter
÷128
4
Programmable Postscaler
1:1 to 1:32,768
23.2.1
Register 23-14 shows the WDTCON register. This is a
readable and writable register which contains a control
bit that allows software to override the WDT enable
Configuration bit, but only if the Configuration bit has
disabled the WDT.
Note 1: The CLRWDT and SLEEP instructions
2: Changing the setting of the IRCF bits
3: When a CLRWDT instruction is executed,
CONTROL REGISTER
clear the WDT and postscaler counts
when executed.
(OSCCON<6:4>) clears the WDT and
postscaler counts.
the postscaler count will be cleared.
Reset
© 2008 Microchip Technology Inc.
WDT
Reset
Wake-up from
Power-Managed
Modes