Datasheet

© 2007 Microchip Technology Inc. DS39599G-page 7
PIC18F2220/2320/4220/4320
1.0 DEVICE OVERVIEW
This document contains device-specific information for
the following devices:
This family offers the advantages of all PIC18 micro-
controllers – namely, high computational performance
at an economical price with the addition of high-
endurance Enhanced Flash program memory. On top
of these features, the PIC18F2220/2320/4220/4320
family introduces design enhancements that make
these microcontrollers a logical choice for many
high-performance, power sensitive applications.
1.1 New Core Features
1.1.1 nanoWatt TECHNOLOGY
All of the devices in the PIC18F2220/2320/4220/4320
family incorporate a range of features that can signifi-
cantly reduce power consumption during operation.
Key items include:
• Alternate Run Modes: By clocking the controller
from the Timer1 source or the internal oscillator
block, power consumption during code execution
can be reduced by as much as 90%.
• Multiple Idle Modes: The controller can also run
with its CPU core disabled, but the peripherals are
still active. In these states, power consumption
can be reduced even further, to as little as 4%, of
normal operation requirements.
• On-the-Fly Mode Switching: The power-managed
modes are invoked by user code during operation,
allowing the user to incorporate power-saving ideas
into their application’s software design.
• Lower Consumption in Key Modules: The power
requirements for both Timer1 and the Watchdog
Timer have been reduced by up to 80%, with typical
values of 1.8 and 2.2 μA, respectively.
1.1.2 MULTIPLE OSCILLATOR OPTIONS
AND FEATURES
All of the devices in the PIC18F2220/2320/4220/4320
family offer nine different oscillator options, allowing
users a wide range of choices in developing application
hardware. These include:
• Four Crystal modes using crystals or ceramic
resonators.
• Two External Clock modes offering the option of
using two pins (oscillator input and a divide-by-4
clock output) or one pin (oscillator input with the
second pin reassigned as general I/O).
• Two External RC Oscillator modes with the same
pin options as the External Clock modes.
• An internal oscillator block, which provides a
31 kHz INTRC clock and an 8 MHz clock with
6 program selectable divider ratios (4 MHz to
125 kHz) for a total of 8 clock frequencies.
Besides its availability as a clock source, the internal
oscillator block provides a stable reference source that
gives the family additional features for robust
operation:
• Fail-Safe Clock Monitor: This option constantly
monitors the main clock source against a refer-
ence signal provided by the internal oscillator. If a
clock failure occurs, the controller is switched to
the internal oscillator block, allowing for continued
low-speed operation or a safe application
shutdown.
• Two-Speed Start-up: This option allows the
internal oscillator to serve as the clock source
from Power-on Reset, or wake-up from Sleep
mode, until the primary clock source is available.
This allows for code execution during what would
otherwise be the clock start-up interval and can
even allow an application to perform routine back-
ground activities and return to Sleep without
returning to full power operation.
1.2 Other Special Features
• Memory Endurance: The Enhanced Flash cells
for both program memory and data EEPROM are
rated to last for many thousands of erase/write
cycles – up to 100,000 for program memory and
1,000,000 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 routine
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.
• 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 dis-
abling PWM outputs on interrupt or other select
conditions and Auto-Restart to reactivate outputs
once the condition has cleared.
• Addressable USART: This serial communication
module is capable of standard RS-232 operation
using the internal oscillator block, removing the
need for an external crystal (and its accompany-
ing power requirement) in applications that talk to
the outside world.
• 10-Bit A/D Converter: This module incorporates
programmable acquisition time, allowing for a
channel to be selected and a conversion to be ini-
tiated without waiting for a sampling period and
thus, reduce code overhead.
• Extended Watchdog Timer (WDT): This
enhanced version incorporates a 16-bit prescaler,
allowing a time-out range from 4 ms to over
2 minutes, that is stable across operating voltage
and temperature.
• PIC18F2220 • PIC18F4220
• PIC18F2320 • PIC18F4320