PIC18F2420 MICROCHIP [Microchip Technology], PIC18F2420 Datasheet - Page 9

• Manufacturer Part Number: PIC18F2420
• Description: 28/40/44-Pin Enhanced Flash Microcontrollers with 10-Bit A/D and nanoWatt Technology
• Manufacturer: MICROCHIP [Microchip Technology]

1.0
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 PIC18F2420/2520/4420/4520
family introduces design enhancements that make
these microcontrollers a logical choice for many high-
performance, power sensitive applications.
1.1
1.1.1
All of the devices in the PIC18F2420/2520/4420/4520
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
• Multiple Idle Modes: The controller can also run
• On-the-fly Mode Switching: The power
• Low Consumption in Key Modules: The
 2004 Microchip Technology Inc.
• PIC18F2420
• PIC18F2520
• PIC18F4420
• PIC18F4520
from the Timer1 source or the internal oscillator
block, power consumption during code execution
can be reduced by as much as 90%.
with its CPU core disabled but the peripherals still
active. In these states, power consumption can be
reduced even further, to as little as 4% of normal
operation requirements.
managed modes are invoked by user code during
operation, allowing the user to incorporate power-
saving ideas into their application’s software
design.
power requirements for both Timer1 and the
Watchdog Timer are minimized. See
Section 26.0 “Electrical Characteristics”
for values.
DEVICE OVERVIEW
New Core Features
nanoWatt TECHNOLOGY
• PIC18LF2420
• PIC18LF2520
• PIC18LF4420
• PIC18LF4520
PIC18F2420/2520/4420/4520
Preliminary
1.1.2
All of the devices in the PIC18F2420/2520/4420/4520
family offer ten different oscillator options, allowing
users a wide range of choices in developing application
hardware. These include:
• Four Crystal modes, using crystals or ceramic
• Two External Clock modes, offering the option of
• Two External RC Oscillator modes with the same
• An internal oscillator block which provides an
• A Phase Lock Loop (PLL) frequency multiplier,
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
• Two-Speed Start-up: This option allows the
resonators
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)
pin options as the External Clock modes
8 MHz clock and an INTRC source (approxi-
mately 31 kHz), as well as a range of 6 user
selectable clock frequencies, between 125 kHz to
4 MHz, for a total of 8 clock frequencies. This
option frees the two oscillator pins for use as
additional general purpose I/O.
available to both the high-speed crystal and inter-
nal oscillator modes, which allows clock speeds of
up to 40 MHz. Used with the internal oscillator, the
PLL gives users a complete selection of clock
speeds, from 31 kHz to 32 MHz – all without using
an external crystal or clock circuit.
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.
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.
MULTIPLE OSCILLATOR OPTIONS
AND FEATURES
DS39631A-page 7