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PIC18F25K20T-ISS Datasheet, PDF (12/456 Pages) Microchip Technology – 28/40/44-Pin Flash Microcontrollers with nanoWatt XLP Technology
PIC18F2XK20/4XK20
1.2 Other Special Features
• Memory Endurance: The Flash cells for both
program memory and data EEPROM are rated to
last for many thousands of erase/write cycles – up to
10K for program memory and 100K for EEPROM.
Data retention without refresh is conservatively
estimated to be greater than 40 years.
• Self-programmability: These devices can write
to their own program memory spaces under inter-
nal software control. By using a bootloader rou-
tine located in the protected Boot Block at the top
of program memory, it becomes possible to create
an application that can update itself in the field.
• Extended Instruction Set: The PIC18F2XK20/
4XK20 family introduces an optional extension to
the PIC18 instruction set, which adds 8 new
instructions and an Indexed Addressing mode.
This extension, enabled as a device configuration
option, has been specifically designed to optimize
re-entrant application code originally developed in
high-level languages, such as C.
• Enhanced CCP module: In PWM mode, this
module provides 1, 2 or 4 modulated outputs for
controlling half-bridge and full-bridge drivers.
Other features include:
- Auto-Shutdown, for disabling PWM outputs
on interrupt or other select conditions
- Auto-Restart, to reactivate outputs once the
condition has cleared
- Output steering to selectively enable one or
more of 4 outputs to provide the PWM signal.
• Enhanced Addressable USART: This serial
communication module is capable of standard
RS-232 operation and provides support for the LIN
bus protocol. Other enhancements include
automatic baud rate detection and a 16-bit Baud
Rate Generator for improved resolution. When the
microcontroller is using the internal oscillator
block, the USART provides stable operation for
applications that talk to the outside world without
using an external crystal (or its accompanying
power requirement).
• 10-bit A/D Converter: This module incorporates
programmable acquisition time, allowing for a
channel to be selected and a conversion to be
initiated without waiting for a sampling period and
thus, reduce code overhead.
• Extended Watchdog Timer (WDT): This
enhanced version incorporates a 16-bit
postscaler, allowing an extended time-out range
that is stable across operating voltage and
temperature. See Section 26.0 “Electrical
Characteristics” for time-out periods.
1.3 Details on Individual Family
Members
Devices in the PIC18F2XK20/4XK20 family are avail-
able in 28-pin and 40/44-pin packages. Block diagrams
for the two groups are shown in Figure 1-1 and
Figure 1-2.
The devices are differentiated from each other in five
ways:
1. Flash program memory (8 Kbytes for
PIC18F23K20/43K20 devices, 16 Kbytes for
PIC18F24K20/44K20 devices, 32 Kbytes for
PIC18F25K20/45K20 AND 64 Kbytes for
PIC18F26K20/46K20).
2. A/D channels (11 for 28-pin devices, 14 for
40/44-pin devices).
3. I/O ports (3 bidirectional ports on 28-pin devices,
5 bidirectional ports on 40/44-pin devices).
4. Parallel Slave Port (present only on 40/44-pin
devices).
All other features for devices in this family are identical.
These are summarized in Table 1-1.
The pinouts for all devices are listed in the pin summary
tables: Table 1 and Table 2, and I/O description tables:
Table 1-2 and Table 1-3.
DS41303G-page 12
 2010 Microchip Technology Inc.