PIC18F2423/2523/4423/4523
Data Sheet
28/40/44-Pin, Enhanced Flash
Microcontrollers with 12-Bit A/D
and nanoWatt Technology
© 2009 Microchip Technology Inc.
DS39755C
Note the following details of the code protection feature on Microchip devices:
•
Microchip products meet the specification contained in their particular Microchip Data Sheet.
•
Microchip believes that its family of products is one of the most secure families of its kind on the market today, when used in the
intended manner and under normal conditions.
•
There are dishonest and possibly illegal methods used to breach the code protection feature. All of these methods, to our
knowledge, require using the Microchip products in a manner outside the operating specifications contained in Microchip’s Data
Sheets. Most likely, the person doing so is engaged in theft of intellectual property.
•
Microchip is willing to work with the customer who is concerned about the integrity of their code.
•
Neither Microchip nor any other semiconductor manufacturer can guarantee the security of their code. Code protection does not
mean that we are guaranteeing the product as “unbreakable.”
Code protection is constantly evolving. We at Microchip are committed to continuously improving the code protection features of our
products. Attempts to break Microchip’s code protection feature may be a violation of the Digital Millennium Copyright Act. If such acts
allow unauthorized access to your software or other copyrighted work, you may have a right to sue for relief under that Act.
Information contained in this publication regarding device
applications and the like is provided only for your convenience
and may be superseded by updates. It is your responsibility to
ensure that your application meets with your specifications.
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Trademarks
The Microchip name and logo, the Microchip logo, dsPIC,
KEELOQ, KEELOQ logo, MPLAB, PIC, PICmicro, PICSTART,
rfPIC and UNI/O are registered trademarks of Microchip
Technology Incorporated in the U.S.A. and other countries.
FilterLab, Hampshire, HI-TECH C, Linear Active Thermistor,
MXDEV, MXLAB, SEEVAL and The Embedded Control
Solutions Company are registered trademarks of Microchip
Technology Incorporated in the U.S.A.
Analog-for-the-Digital Age, Application Maestro, CodeGuard,
dsPICDEM, dsPICDEM.net, dsPICworks, dsSPEAK, ECAN,
ECONOMONITOR, FanSense, HI-TIDE, In-Circuit Serial
Programming, ICSP, Mindi, MiWi, MPASM, MPLAB Certified
logo, MPLIB, MPLINK, mTouch, Octopus, Omniscient Code
Generation, PICC, PICC-18, PICDEM, PICDEM.net, PICkit,
PICtail, PIC32 logo, REAL ICE, rfLAB, Select Mode, Total
Endurance, TSHARC, UniWinDriver, WiperLock and ZENA
are trademarks of Microchip Technology Incorporated in the
U.S.A. and other countries.
SQTP is a service mark of Microchip Technology Incorporated
in the U.S.A.
All other trademarks mentioned herein are property of their
respective companies.
© 2009, Microchip Technology Incorporated, Printed in the
U.S.A., All Rights Reserved.
Printed on recycled paper.
Microchip received ISO/TS-16949:2002 certification for its worldwide
headquarters, design and wafer fabrication facilities in Chandler and
Tempe, Arizona; Gresham, Oregon and design centers in California
and India. The Company’s quality system processes and procedures
are for its PIC® MCUs and dsPIC® DSCs, KEELOQ® code hopping
devices, Serial EEPROMs, microperipherals, nonvolatile memory and
analog products. In addition, Microchip’s quality system for the design
and manufacture of development systems is ISO 9001:2000 certified.
DS39755C-page 2
© 2009 Microchip Technology Inc.
PIC18F2423/2523/4423/4523
28/40/44-Pin, Enhanced Flash Microcontrollers with
12-Bit A/D and nanoWatt Technology
Power Management Features:
Peripheral Highlights (Continued):
•
•
•
•
•
•
•
•
•
•
• Master Synchronous Serial Port (MSSP) module
Supporting 3-Wire SPI (all four modes) and I2C™
Master and Slave modes
• Enhanced USART module:
- Support for RS-485, RS-232 and LIN/J2602
- RS-232 operation using internal oscillator
block (no external crystal required)
- Auto-wake-up on Start bit
- Auto-Baud Detect (ABD)
Run: CPU on, Peripherals on
Idle: CPU off, Peripherals on
Sleep: CPU off, Peripherals off
Ultra Low 50 nA Input Leakage
Run mode Currents Down to 11 μA Typical
Idle mode Currents Down to 2.5 μA Typical
Sleep mode Current Down to 100 μA Typical
Timer1 Oscillator: 900 nA, 32 kHz, 2V
Watchdog Timer: 1.4 μA, 2V Typical
Two-Speed Oscillator Start-up
Special Microcontroller Features:
Flexible Oscillator Structure:
• C Compiler Optimized Architecture: Optional
Extended Instruction Set Designed to Optimize
Re-Entrant Code
• 100,000 Erase/Write Cycle, Enhanced Flash
Program Memory Typical
• 1,000,000 Erase/Write Cycle, Data EEPROM
Memory Typical
• Flash/Data EEPROM Retention: 100 Years Typical
• Self-Programmable under Software Control
• Priority Levels for Interrupts
• 8 x 8 Single-Cycle Hardware Multiplier
• Extended Watchdog Timer (WDT): Programmable
Period, from 4 ms to 131s
• Single-Supply In-Circuit Serial Programming™
(ICSP™) via Two Pins
• In-Circuit Debug (ICD) via Two Pins
• Operating Voltage Range: 2.0V to 5.5V
• Programmable, 16-Level High/Low-Voltage
Detection (HLVD) module: Supports Interrupt on
High/Low-Voltage Detection
• Programmable Brown-out Reset (BOR): With
Software-Enable Option
Peripheral Highlights:
• 12-Bit, Up to 13-Channel Analog-to-Digital Converter
module (A/D):
- Auto-acquisition capability
- Conversion available during Sleep mode
• Dual Analog Comparators with Input Multiplexing
• High-Current Sink/Source 25 mA/25 mA
• Three Programmable External Interrupts
• Four Input Change Interrupts
• Up to Two Capture/Compare/PWM (CCP)
modules, One with Auto-Shutdown (28-pin devices)
• Enhanced Capture/Compare/PWM (ECCP) module
(40/44-pin devices only):
- One, two or four PWM outputs
- Selectable polarity
- Programmable dead time
- Auto-shutdown and auto-restart
Program Memory
Device
PIC18F2423
PIC18F2523
PIC18F4423
PIC18F4523
Data Memory
Flash # Single-Word SRAM EEPROM
(bytes) Instructions (bytes) (bytes)
16K
32K
16K
32K
8192
16384
8192
16384
© 2009 Microchip Technology Inc.
Note:
768
1536
768
1536
256
256
256
256
This document is supplemented by the
“PIC18F2420/2520/4420/4520 Data Sheet”
(DS39631). See Section 1.0 “Device
Overview”.
MSSP
I/O
12-Bit
A/D (ch)
CCP/
ECCP
(PWM)
SPI
Master
I2C™
25
25
36
36
10
10
13
13
2/0
2/0
1/1
1/1
Y
Y
Y
Y
Y
Y
Y
Y
EUSART
• Four Crystal modes, up to 40 MHz
• 4x Phase Lock Loop (PLL) – Available for Crystal
and Internal Oscillators
• Two External RC modes, up to 4 MHz
• Two External Clock modes, up to 40 MHz
• Internal Oscillator Block:
- Fast wake from Sleep and Idle, 1 μs typical
- 8 user-selectable frequencies, from 31 kHz to 8 MHz
- Provides a complete range of clock speeds,
from 31 kHz to 32 MHz, when used with PLL
- User-tunable to Compensate for Frequency Drift
• Secondary Oscillator using Timer1 @ 32 kHz
• Fail-Safe Clock Monitor:
- Allows for safe shutdown if peripheral clock stops
Comp.
Timers
8/16-Bit
1
1
1
1
2
2
2
2
1/3
1/3
1/3
1/3
DS39755C-page 3
PIC18F2423/2523/4423/4523
Pin Diagrams
28-Pin PDIP, SOIC
1
2
3
4
5
6
7
8
9
10
11
12
13
14
PIC18F2423
PIC18F2523
MCLR/VPP/RE3
RA0/AN0
RA1/AN1
RA2/AN2/VREF-/CVREF
RA3/AN3/VREF+
RA4/T0CKI/C1OUT
RA5/AN4/SS/HLVDIN/C2OUT
VSS
OSC1/CLKI(3)/RA7
OSC2/CLKO(3)/RA6
RC0/T1OSO/T13CKI
RC1/T1OSI/CCP2(2)
RC2/CCP1
RC3/SCK/SCL
RB7/KBI3/PGD
RB6//KBI2/PGC
RB5/KBI1/PGM
RB4/KBI0/AN11
RB3/AN9/CCP2(2)
RB2/INT2/AN8
RB1/INT1/AN10
RB0/INT0/FLT0/AN12
VDD
VSS
RC7/RX/DT
RC6/TX/CK
RC5/SDO
RC4/SDI/SDA
28
27
26
25
24
23
22
21
20
19
18
17
16
15
MCLR/VPP/RE3
RB7/KBI3/PGD
RB6/KBI2/PGC
RB5/KBI1/PGM
RB4KBI0/AN11
RA1/AN1
RA0/AN0
28-Pin QFN(1)
28 27 26 25 24 23 22
1
2
3
4
5
6
7
PIC18F2423
PIC18F2523
8 9 10 11 12 13 14
21
20
19
18
17
16
15
RB3/AN9/CCP2(2)
RB2/INT2/AN8
RB1/INT1/AN10
RB0/INT0/FLT0/AN12
VDD
VSS
RC7/RX/DT
RC0/T1OSO/T13CKI
RC1/T1OSI/CCP2(2)
RC2/CCP1
RC3/SCK/SCL
RC4/SDI/SDA
RC5/SDO
RC6/TX/CK
RA2/AN2/VREF-/CVREF
RA3/AN3/VREF+
RA4/T0CKI/C1OUT
RA5/AN4/SS/HLVDIN/C2OUT
VSS
OSC1/CLKI(3)/RA7
(3)
OSC2/CLKO /RA6
Note 1:
2:
3:
DS39755C-page 4
It is recommended to connect the bottom pad of QFN package parts to VSS.
RB3 is the alternate pin for CCP2 multiplexing.
OSC1/CLKI and OSC2/CLKO are only available in select oscillator modes and when these pins are not
being used as digital I/O. For additional information, see Section 2.0 “Oscillator Configurations” of the
“PIC18F2420/2520/4420/4520 Data Sheet” (DS39631).
© 2009 Microchip Technology Inc.
PIC18F2423/2523/4423/4523
Pin Diagrams (Continued)
40-Pin PDIP
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
40
39
38
37
36
35
34
33
32
31
30
29
28
27
26
25
24
23
22
21
PIC18F4423
PIC18F4523
MCLR/VPP/RE3
RA0/AN0
RA1/AN1
RA2/AN2/VREF-/CVREF
RA3/AN3/VREF+
RA4/T0CKI/C1OUT
RA5/AN4/SS/HLVDIN/C2OUT
RE0/RD/AN5
RE1/WR/AN6
RE2/CS/AN7
VDD
VSS
OSC1/CLKI(2)/RA7
OSC2/CLKO(2)/RA6
RC0/T1OSO/T13CKI
RC1/T1OSI/CCP2(1)
RC2/CCP1/P1A
RC3/SCK/SCL
RD0/PSP0
RD1/PSP1
RB7/KBI3/PGD
RB6/KBI2/PGC
RB5/KBI1/PGM
RB4/KBI0/AN11
RB3/AN9/CCP2(1)
RB2/INT2/AN8
RB1/INT1/AN10
RB0/INT0/FLT0/AN12
VDD
VSS
RD7/PSP7/P1D
RD6/PSP6/P1C
RD5/PSP5/P1B
RD4/PSP4
RC7/RX/DT
RC6/TX/CK
RC5/SDO
RC4/SDI/SDA
RD3/PSP3
RD2/PSP2
44
43
42
41
40
39
38
37
36
35
34
RC6/TX/CK
RC5/SDO
RC4/SDI/SDA
RD3/PSP3
RD2/PSP2
RD1/PSP1
RD0/PSP0
RC3/SCK/SCL
RC2/CCP1/P1A
RC1/T1OSI/CCP2(1)
NC
44-Pin TQFP
PIC18F4423
PIC18F4523
33
32
31
30
29
28
27
26
25
24
23
12
13
14
15
16
17
18
19
20
21
22
1
2
3
4
5
6
7
8
9
10
11
NC
RC0/T1OSO/T13CKI
OSC2/CLKO(2)/RA6
OSC1/CLKI(2)/RA7
VSS
VDD
RE2/CS/AN7
RE1/WR/AN6
RE0/RD/AN5
RA5/AN4/SS/HLVDIN/C2OUT
RA4/T0CKI/C1OUT
NC
NC
RB4/KBI0/AN11
RB5/KBI1/PGM
RB6/KBI2/PGC
RB7/KBI3/PGD
MCLR/VPP/RE3
RA0/AN0
RA1/AN1
RA2/AN2/VREF-/CVREF
RA3/AN3/VREF+
RC7/RX/DT
RD4/PSP4
RD5/PSP5/P1B
RD6/PSP6/P1C
RD7/PSP7/P1D
VSS
VDD
RB0/INT0/FLT0/AN12
RB1/INT1/AN10
RB2/INT2/AN8
RB3/AN9/CCP2(1)
Note 1:
2:
RB3 is the alternate pin for CCP2 multiplexing.
OSC1/CLKI and OSC2/CLKO are only available in select oscillator modes and when these pins are not
being used as digital I/O. For additional information, see Section 2.0 “Oscillator Configurations” of the
“PIC18F2420/2520/4420/4520 Data Sheet” (DS39631).
© 2009 Microchip Technology Inc.
DS39755C-page 5
PIC18F2423/2523/4423/4523
Pin Diagrams (Continued)
PIC18F4423
PIC18F4523
33
32
31
30
29
28
27
26
25
24
23
12
13
14
15
16
17
18
19
20
21
22
1
2
3
4
5
6
7
8
9
10
11
OSC2/CLKO(3)/RA6
OSC1/CLKI(3)/RA7
VSS
VSS
VDD
VDD
RE2/CS/AN7
RE1/WR/AN6
RE0/RD/AN5
RA5/AN4/SS/HLVDIN/C2OUT
RA4/T0CKI/C1OUT
RB3/AN9/CCP2(2)
NC
RB4/KBI0/AN11
RB5/KBI1/PGM
RB6/KBI2/PGC
RB7/KBI3/PGD
MCLR/VPP/RE3
RA0/AN0
RA1/AN1
RA2/AN2/VREF-/CVREF
RA3/AN3/VREF+
RC7/RX/DT
RD4/PSP4
RD5/PSP5/P1B
RD6/PSP6/P1C
RD7/PSP7/P1D
VSS
VDD
VDD
RB0/INT0/FLT0/AN12
RB1/INT1/AN10
RB2/INT2/AN8
44
43
42
41
40
39
38
37
36
35
34
RC6/TX/CK
RC5/SDO
RC4/SDI/SDA
RD3/PSP3
RD2/PSP2
RD1/PSP1
RD0/PSP0
RC3/SCK/SCL
RC2/CCP1/P1A
RC1/T1OSI/CCP2(2)
RC0/T1OSO/T13CKI
44-Pin QFN(1)
Note 1:
2:
3:
It is recommended to connect the bottom pad of QFN package parts to VSS.
RB3 is the alternate pin for CCP2 multiplexing.
OSC1/CLKI and OSC2/CLKO are only available in select oscillator modes and when these pins are not
being used as digital I/O. For additional information, see Section 2.0 “Oscillator Configurations” of the
“PIC18F2420/2520/4420/4520 Data Sheet” (DS39631).
DS39755C-page 6
© 2009 Microchip Technology Inc.
PIC18F2423/2523/4423/4523
Table of Contents
1.0 Device Overview .......................................................................................................................................................................... 9
2.0 12-Bit Analog-to-Digital Converter (A/D) Module ....................................................................................................................... 25
3.0 Special Features of the CPU...................................................................................................................................................... 35
4.0 Electrical Characteristics ............................................................................................................................................................ 37
5.0 Packaging Information................................................................................................................................................................ 43
Appendix A: Revision History............................................................................................................................................................... 45
Appendix B: Device Differences .......................................................................................................................................................... 45
Appendix C: Conversion Considerations ............................................................................................................................................. 46
Appendix D: Migration from Baseline to Enhanced Devices................................................................................................................ 46
Appendix E: Migration from Mid-Range to Enhanced Devices ............................................................................................................ 47
Appendix F: Migration from High-End to Enhanced Devices ............................................................................................................... 47
Index ................................................................................................................................................................................................... 49
The Microchip Web Site ....................................................................................................................................................................... 51
Customer Change Notification Service ................................................................................................................................................ 51
Customer Support ................................................................................................................................................................................ 51
Reader Response ................................................................................................................................................................................ 52
Product Identification System .............................................................................................................................................................. 53
© 2009 Microchip Technology Inc.
DS39755C-page 7
PIC18F2423/2523/4423/4523
TO OUR VALUED CUSTOMERS
It is our intention to provide our valued customers with the best documentation possible to ensure successful use of your Microchip
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The last character of the literature number is the version number, (e.g., DS30000A is version A of document DS30000).
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DS39755C-page 8
© 2009 Microchip Technology Inc.
PIC18F2423/2523/4423/4523
1.0
DEVICE OVERVIEW
This document contains device-specific information for
the following devices:
• PIC18F2423
• PIC18LF2423
• PIC18F2523
• PIC18LF2523
• PIC18F4423
• PIC18LF4423
• PIC18F4523
• PIC18LF4523
Note: This data sheet documents only the devices’
features and specifications that are in addition
to, or different from, the features and specifications of the PIC18F2420/2520/4420/4520
devices. For information on the features and
specifications shared by the PIC18F2423/
2523/4423/4523 and PIC18F2420/2520/
4420/4520 devices, see the “PIC18F2420/
2520/4420/4520 Data Sheet” (DS39631).
This family offers the advantages of all PIC18
microcontrollers – namely, high computational performance at an economical price – with the addition of
high-endurance, Enhanced Flash program memory.
On top of these features, the PIC18F2423/2523/4423/
4523 family introduces design enhancements that
make these microcontrollers a logical choice for many
high-performance, power-sensitive applications.
1.1
1.1.1
New Core Features
nanoWatt TECHNOLOGY
All of the devices in the PIC18F2423/2523/4423/4523
family incorporate a range of features that can significantly 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 also can run
with its CPU core disabled and the peripherals 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.
• Low Consumption in Key Modules: The power
requirements for both Timer1 and the Watchdog
Timer are minimized. See Section 4.0 “Electrical
Characteristics” for values.
© 2009 Microchip Technology Inc.
1.1.2
MULTIPLE OSCILLATOR OPTIONS
AND FEATURES
All of the devices in the PIC18F2423/2523/4423/4523
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
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 that offers eight clock
frequencies: an 8 MHz clock and an INTRC source
(approximately 31 kHz), as well as a range of six
user-selectable clock frequencies, between
125 kHz to 4 MHz. This option frees the two
oscillator pins for use as additional general
purpose I/O.
• A Phase Lock Loop (PLL) frequency multiplier,
available to both the High-Speed Crystal and
Internal Oscillator modes, allowing clock speeds
of up to 40 MHz from the HS clock source. 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.
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: Constantly monitors
the main clock source against a reference signal
provided by the internal oscillator. If a clock failure
occurs, the controller is switched to the internal
oscillator block, allowing for continued operation
or a safe application shutdown.
• Two-Speed Start-up: 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.
DS39755C-page 9
PIC18F2423/2523/4423/4523
1.2
Other Special Features
• 12-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,
thereby reducing code overhead.
• 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 internal software control. By using a bootloader routine
located in the protected Boot Block at the top of
program memory, it is possible to create an
application that can update itself in the field.
• Extended Instruction Set: The PIC18F2423/
2523/4423/4523 family introduces an optional
extension to the PIC18 instruction set that adds
eight 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 one, two or four 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, and auto-restart, to reactivate outputs
once the condition has cleared.
• Enhanced Addressable USART: This serial
communication module is capable of standard
RS-232 operation and provides support for the
LIN/J2602 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 EUSART provides stable
operation for applications that talk to the outside
world without using an external crystal (or its
accompanying power requirement).
• Extended Watchdog Timer (WDT): This
Enhanced version incorporates a 16-bit prescaler,
allowing an extended time-out range that is stable
across operating voltage and temperature. See
Section 4.0 “Electrical Characteristics” for
time-out periods.
DS39755C-page 10
1.3
Details on Individual Family
Members
Devices in the PIC18F2423/2523/4423/4523 family are
available 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 these
ways:
• Flash Program Memory:
- PIC18F2423/4423 devices – 16 Kbytes
- PIC18F2523/4523 devices – 32 Kbytes
• A/D Channels:
- PIC18F2423/2523 devices – 10
- PIC18F4423/4523 devices – 13
• I/O Ports:
- PIC18F2423/2523 devices – Three bidirectional
ports
- PIC18F4423/4523 devices – Five bidirectional
ports
• CCP and Enhanced CCP Implementation:
- PIC18F2423/2523 devices – Two standard
CCP modules
- PIC18F4423/4523 devices – One standard
CCP module and one ECCP module
• Parallel Slave Port – Present only on
PIC18F4423/4523 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 Table 1-2 and
Table 1-3.
Members of the PIC18F2423/2523/4423/4523 family
are available only as low-voltage devices, designated
by “LF” (such as PIC18LF2423), and function over an
extended VDD range of 2.0V to 5.5V.
© 2009 Microchip Technology Inc.
PIC18F2423/2523/4423/4523
TABLE 1-1:
DEVICE FEATURES
Features
Operating Frequency
PIC18F2423
PIC18F2523
PIC18F4423
PIC18F4523
DC – 40 MHz
DC – 40 MHz
DC – 40 MHz
DC – 40 MHz
Program Memory (Bytes)
16,384
32,768
16,384
32,768
Program Memory (Instructions)
8,192
16,384
8,192
16,384
Data Memory (Bytes)
768
1,536
768
1,536
Data EEPROM Memory (Bytes)
256
256
256
256
Interrupt Sources
19
19
20
20
Ports A, B, C, D, E
I/O Ports
Ports A, B, C, (E)
Ports A, B, C, (E)
Ports A, B, C, D, E
Timers
4
4
4
4
Capture/Compare/PWM Modules
2
2
1
1
Enhanced
Capture/Compare/PWM Modules
0
0
1
1
MSSP,
Enhanced USART
MSSP,
Enhanced USART
MSSP,
Enhanced USART
MSSP,
Enhanced USART
Serial Communications
Parallel Communications (PSP)
No
No
Yes
Yes
12-Bit Analog-to-Digital Module
10 Input Channels
10 Input Channels
13 Input Channels
13 Input Channels
Resets (and Delays)
Programmable
High/Low-Voltage Detect
Programmable Brown-out Reset
Instruction Set
Packages
© 2009 Microchip Technology Inc.
POR, BOR,
POR, BOR,
POR, BOR,
POR, BOR,
RESET Instruction,
RESET Instruction,
RESET Instruction,
RESET Instruction,
Stack Full, Stack
Stack Full, Stack
Stack Full, Stack
Stack Full, Stack
Underflow (PWRT, OST), Underflow (PWRT, OST), Underflow (PWRT, OST), Underflow (PWRT, OST),
MCLR (optional), WDT
MCLR (optional), WDT
MCLR (optional), WDT
MCLR (optional), WDT
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
75 Instructions;
83 with Extended
Instruction Set enabled
75 Instructions;
83 with Extended
Instruction Set enabled
75 Instructions;
83 with Extended
Instruction Set enabled
75 Instructions;
83 with Extended
Instruction Set enabled
28-Pin PDIP
28-Pin SOIC
28-Pin QFN
28-Pin PDIP
28-Pin SOIC
28-Pin QFN
40-Pin PDIP
44-Pin QFN
44-Pin TQFP
40-Pin PDIP
44-Pin QFN
44-Pin TQFP
DS39755C-page 11
PIC18F2423/2523/4423/4523
FIGURE 1-1:
PIC18F2423/2523 (28-PIN) BLOCK DIAGRAM
Data Bus
Table Pointer
Data Latch
8
8
inc/dec logic
20
Address Latch
PCU PCH PCL
Program Counter
31 Level Stack
12
Data Address
4
BSR
Address Latch
Program Memory
(16/32 Kbytes)
RA0/AN0
RA1/AN1
RA2/AN2/VREF-/CVREF
RA3/AN3/VREF+
RA4/T0CKI/C1OUT
RA5/AN4/SS/HLVDIN/C2OUT
OSC2/CLKO(3)/RA6
OSC1/CLKI(3)/RA7
Data Memory
( 3.9 Kbytes )
PCLATU PCLATH
21
PORTA
STKPTR
4
Access
Bank
12
FSR0
FSR1
FSR2
Data Latch
12
PORTB
8
Instruction Bus
RB0/INT0/FLT0/AN12
RB1/INT1/AN10
RB2/INT2/AN8
RB3/AN9/CCP2(1)
RB4/KBI0/AN11
RB5/KBI1/PGM
RB6/KBI2/PGC
RB7/KBI3/PGD
inc/dec
logic
Table Latch
Address
Decode
ROM Latch
IR
Instruction
Decode and
Control
8
State Machine
Control Signals
PRODH PRODL
PORTC
3
8
W
BITOP
8
Internal
Oscillator
Block
Power-up
Timer
T1OSI
INTRC
Oscillator
T1OSO
8 MHz
Oscillator
Oscillator
Start-up Timer
Power-on
Reset
OSC1(3)
OSC2(3)
Watchdog
Timer
Brown-out
Reset
Fail-Safe
Clock Monitor
Single-Supply
Programming
In-Circuit
Debugger
MCLR(2)
VDD, VSS
8
8
8
8
ALU
8
Precision
Band Gap
Reference
PORTE
MCLR/VPP/RE3(2)
BOR
HLVD
Data
EEPROM
Timer0
Timer1
Timer2
Timer3
Comparator
CCP1
CCP2
MSSP
EUSART
ADC
12-Bit
Note
RC0/T1OSO/T13CKI
RC1/T1OSI/CCP2(1)
RC2/CCP1
RC3/SCK/SCL
RC4/SDI/SDA
RC5/SDO
RC6/TX/CK
RC7/RX/DT
8 x 8 Multiply
1:
CCP2 is multiplexed with RC1 when Configuration bit, CCP2MX, is set or RB3 when CCP2MX is not set.
2:
RE3 is only available when MCLR functionality is disabled.
3:
OSC1/CLKI and OSC2/CLKO are only available in select oscillator modes and when these pins are not being used as digital I/O.
For additional information, see Section 2.0 “Oscillator Configurations” of the “PIC18F2420/2520/4420/4520 Data Sheet” (DS39631).
DS39755C-page 12
© 2009 Microchip Technology Inc.
PIC18F2423/2523/4423/4523
FIGURE 1-2:
PIC18F4423/4523 (40/44-PIN) BLOCK DIAGRAM
Data Bus
Table Pointer
Data Memory
( 3.9 Kbytes )
PCLATU PCLATH
21
20
Address Latch
PCU PCH PCL
Program Counter
12
Data Address
31 Level Stack
4
BSR
Address Latch
Program Memory
(16/32 Kbytes)
STKPTR
Data Latch
8
12
FSR0
FSR1
FSR2
PORTB
RB0/INT0/FLT0/AN12
RB1/INT1/AN10
RB2/INT2/AN8
RB3/AN9/CCP2(1)
RB4/KBI0/AN11
RB5/KBI1/PGM
RB6/KBI2/PGC
RB7/KBI3/PGD
4
Access
Bank
12
inc/dec
logic
Table Latch
PORTC
Address
Decode
ROM Latch
Instruction Bus
RA0/AN0
RA1/AN1
RA2/AN2/VREF-/CVREF
RA3/AN3/VREF+
RA4/T0CKI/C1OUT
RA5/AN4/SS/HLVDIN/C2OUT
OSC2/CLKO(3)/RA6
OSC1/CLKI(3)/RA7
Data Latch
8
8
inc/dec logic
PORTA
RC0/T1OSO/T13CKI
RC1/T1OSI/CCP2(1)
RC2/CCP1/P1A
RC3/SCK/SCL
RC4/SDI/SDA
RC5/SDO
RC6/TX/CK
RC7/RX/DT
IR
8
State Machine
Control Signals
Instruction
Decode and
Control
PRODH PRODL
3
8 x 8 Multiply
8
W
BITOP
8
Internal
Oscillator
Block
Power-up
Timer
T1OSI
INTRC
Oscillator
T1OSO
8 MHz
Oscillator
Oscillator
Start-up Timer
Power-on
Reset
OSC1(3)
OSC2(3)
MCLR(2)
VDD, VSS
Watchdog
Timer
Brown-out
Reset
Fail-Safe
Clock Monitor
Single-Supply
Programming
In-Circuit
Debugger
8
RD0/PSP0:RD4/PSP4
RD5/PSP5/P1B
RD6/PSP6/P1C
RD7/PSP7/P1D
8
8
8
ALU
8
PORTE
Precision
Band Gap
Reference
BOR
HLVD
Data
EEPROM
Timer0
Timer1
Timer2
Timer3
Comparator
ECCP1
CCP2
MSSP
EUSART
ADC
12-Bit
Note
PORTD
RE0/RD/AN5
RE1/WR/AN6
RE2/CS/AN7
MCLR/VPP/RE3(2)
1:
CCP2 is multiplexed with RC1 when Configuration bit, CCP2MX, is set or RB3 when CCP2MX is not set.
2:
RE3 is only available when MCLR functionality is disabled.
3:
OSC1/CLKI and OSC2/CLKO are only available in select oscillator modes and when these pins are not being used as digital I/O.
For additional information, see Section 2.0 “Oscillator Configurations” of the “PIC18F2420/2520/4420/4520 Data Sheet” (DS39631).
© 2009 Microchip Technology Inc.
DS39755C-page 13
PIC18F2423/2523/4423/4523
TABLE 1-2:
PIC18F2423/2523 PINOUT I/O DESCRIPTIONS
Pin Name
MCLR/VPP/RE3
MCLR
Pin Number
Pin Buffer
PDIP,
Type
Type
QFN
SOIC
1
26
VPP
RE3
OSC1/CLKI/RA7
OSC1
9
6
I
ST
P
I
ST
ST
O
—
CLKO
O
—
RA6
I/O
TTL
RA7
OSC2/CLKO/RA6
OSC2
10
Master Clear (input) or programming voltage (input).
Master Clear (Reset) input. This pin is an active-low
Reset to the device.
Programming voltage input.
Digital input.
Oscillator crystal or external clock input.
Oscillator crystal input or external clock source input.
ST buffer when configured in RC mode; CMOS otherwise.
I CMOS
External clock source input. Always associated with pin
function, OSC1. (See related OSC1/CLKI, OSC2/CLKO
pins.)
I/O
TTL
General purpose I/O pin.
I
CLKI
Description
7
Oscillator crystal or clock output.
Oscillator crystal output. Connects to crystal or
resonator in Crystal Oscillator mode.
In RC mode, OSC2 pin outputs CLKO, which has 1/4 the
frequency of OSC1 and denotes the instruction cycle rate.
General purpose I/O pin.
Legend: TTL = TTL compatible input
CMOS = CMOS compatible input or output
ST = Schmitt Trigger input with CMOS levels
I
= Input
O
= Output
P
= Power
I2C = I2C™/SMBus
Note 1: Default assignment for CCP2 when Configuration bit, CCP2MX, is set.
2: Alternate assignment for CCP2 when Configuration bit, CCP2MX, is cleared.
DS39755C-page 14
© 2009 Microchip Technology Inc.
PIC18F2423/2523/4423/4523
TABLE 1-2:
PIC18F2423/2523 PINOUT I/O DESCRIPTIONS (CONTINUED)
Pin Name
Pin Number
Pin Buffer
PDIP,
Type
Type
QFN
SOIC
Description
PORTA is a bidirectional I/O port.
RA0/AN0
RA0
AN0
2
RA1/AN1
RA1
AN1
3
RA2/AN2/VREF-/CVREF
RA2
AN2
VREFCVREF
4
RA3/AN3/VREF+
RA3
AN3
VREF+
5
RA4/T0CKI/C1OUT
RA4
T0CKI
C1OUT
6
RA5/AN4/SS/HLVDIN/
C2OUT
RA5
AN4
SS
HLVDIN
C2OUT
7
27
I/O
TTL
I Analog
Digital I/O.
Analog Input 0.
I/O
TTL
I Analog
Digital I/O.
Analog Input 1.
I/O
TTL
I Analog
I Analog
O Analog
Digital I/O.
Analog Input 2.
A/D reference voltage (low) input.
Comparator reference voltage output.
I/O
TTL
I Analog
I Analog
Digital I/O.
Analog Input 3.
A/D reference voltage (high) input.
I/O
I
O
Digital I/O.
Timer0 external clock input.
Comparator 1 output.
28
1
2
3
ST
ST
—
4
I/O
TTL
I Analog
I
TTL
I Analog
O
—
Digital I/O.
Analog Input 4.
SPI slave select input.
High/Low-Voltage Detect input.
Comparator 2 output.
RA6
See the OSC2/CLKO/RA6 pin.
RA7
See the OSC1/CLKI/RA7 pin.
Legend: TTL = TTL compatible input
CMOS = CMOS compatible input or output
ST = Schmitt Trigger input with CMOS levels
I
= Input
O
= Output
P
= Power
I2C = I2C™/SMBus
Note 1: Default assignment for CCP2 when Configuration bit, CCP2MX, is set.
2: Alternate assignment for CCP2 when Configuration bit, CCP2MX, is cleared.
© 2009 Microchip Technology Inc.
DS39755C-page 15
PIC18F2423/2523/4423/4523
TABLE 1-2:
PIC18F2423/2523 PINOUT I/O DESCRIPTIONS (CONTINUED)
Pin Name
Pin Number
Pin Buffer
PDIP,
Type
Type
QFN
SOIC
Description
PORTB is a bidirectional I/O port. PORTB can be software
programmed for internal weak pull-ups on all inputs.
RB0/INT0/FLT0/AN12
RB0
INT0
FLT0
AN12
21
RB1/INT1/AN10
RB1
INT1
AN10
22
RB2/INT2/AN8
RB2
INT2
AN8
23
RB3/AN9/CCP2
RB3
AN9
CCP2(1)
24
RB4/KBI0/AN11
RB4
KBI0
AN11
25
RB5/KBI1/PGM
RB5
KBI1
PGM
26
RB6/KBI2/PGC
RB6
KBI2
PGC
27
RB7/KBI3/PGD
RB7
KBI3
PGD
28
18
I/O
TTL
I
ST
I
ST
I Analog
Digital I/O.
External Interrupt 0.
PWM Fault input for CCP1.
Analog Input 12.
I/O
TTL
I
ST
I Analog
Digital I/O.
External Interrupt 1.
Analog Input 10.
I/O
TTL
I
ST
I Analog
Digital I/O.
External Interrupt 2.
Analog Input 8.
I/O
TTL
I Analog
I/O
ST
Digital I/O.
Analog Input 9.
Capture 2 input/Compare 2 output/PWM2 output.
I/O
TTL
I
TTL
I Analog
Digital I/O.
Interrupt-on-change pin.
Analog Input 11.
I/O
I
I/O
TTL
TTL
ST
Digital I/O.
Interrupt-on-change pin.
Low-Voltage ICSP™ Programming enable pin.
I/O
I
I/O
TTL
TTL
ST
Digital I/O.
Interrupt-on-change pin.
In-Circuit Debugger and ICSP programming clock pin.
I/O
I
I/O
TTL
TTL
ST
Digital I/O.
Interrupt-on-change pin.
In-Circuit Debugger and ICSP programming data pin.
19
20
21
22
23
24
25
Legend: TTL = TTL compatible input
CMOS = CMOS compatible input or output
ST = Schmitt Trigger input with CMOS levels
I
= Input
O
= Output
P
= Power
I2C = I2C™/SMBus
Note 1: Default assignment for CCP2 when Configuration bit, CCP2MX, is set.
2: Alternate assignment for CCP2 when Configuration bit, CCP2MX, is cleared.
DS39755C-page 16
© 2009 Microchip Technology Inc.
PIC18F2423/2523/4423/4523
TABLE 1-2:
PIC18F2423/2523 PINOUT I/O DESCRIPTIONS (CONTINUED)
Pin Name
Pin Number
Pin Buffer
PDIP,
Type
Type
QFN
SOIC
Description
PORTC is a bidirectional I/O port.
RC0/T1OSO/T13CKI
RC0
T1OSO
T13CKI
11
RC1/T1OSI/CCP2
RC1
T1OSI
CCP2(2)
12
RC2/CCP1
RC2
CCP1
13
RC3/SCK/SCL
RC3
SCK
SCL
14
RC4/SDI/SDA
RC4
SDI
SDA
15
RC5/SDO
RC5
SDO
16
RC6/TX/CK
RC6
TX
CK
17
RC7/RX/DT
RC7
RX
DT
18
RE3
—
VSS
VDD
8
I/O
O
I
Digital I/O.
Timer1 oscillator output.
Timer1/Timer3 external clock input.
9
I/O
ST
I Analog
I/O
ST
Digital I/O.
Timer1 oscillator input.
Capture 2 input/Compare 2 output/PWM2 output.
I/O
I/O
ST
ST
Digital I/O.
Capture 1 input/Compare 1 output/PWM1 output.
I/O
I/O
I/O
ST
ST
I2C
Digital I/O.
Synchronous serial clock input/output for SPI mode.
Synchronous serial clock input/output for I2C™ mode.
I/O
I
I/O
ST
ST
I2C
Digital I/O.
SPI data in.
I2C data I/O.
I/O
O
ST
—
Digital I/O.
SPI data out.
I/O
O
I/O
ST
—
ST
Digital I/O.
EUSART asynchronous transmit.
EUSART synchronous clock (see related RX/DT).
I/O
I
I/O
ST
ST
ST
Digital I/O.
EUSART asynchronous receive.
EUSART synchronous data (see related TX/CK).
—
—
10
11
12
13
14
15
—
8, 19 5, 16
20
ST
—
ST
17
See MCLR/VPP/RE3 pin.
P
—
Ground reference for logic and I/O pins.
P
—
Positive supply for logic and I/O pins.
Legend: TTL = TTL compatible input
CMOS = CMOS compatible input or output
ST = Schmitt Trigger input with CMOS levels
I
= Input
O
= Output
P
= Power
I2C = I2C™/SMBus
Note 1: Default assignment for CCP2 when Configuration bit, CCP2MX, is set.
2: Alternate assignment for CCP2 when Configuration bit, CCP2MX, is cleared.
© 2009 Microchip Technology Inc.
DS39755C-page 17
PIC18F2423/2523/4423/4523
TABLE 1-3:
PIC18F4423/4523 PINOUT I/O DESCRIPTIONS
Pin Name
MCLR/VPP/RE3
MCLR
Pin Number
PDIP
1
Pin Buffer
QFN TQFP Type Type
18
18
VPP
RE3
OSC1/CLKI/RA7
OSC1
13
32
I
ST
P
I
ST
30
I
CLKI
I
RA7
I/O
OSC2/CLKO/RA6
OSC2
14
33
Description
Master Clear (input) or programming voltage (input).
Master Clear (Reset) input. This pin is an active-low
Reset to the device.
Programming voltage input.
Digital input.
Oscillator crystal or external clock input.
Oscillator crystal input or external clock source input.
ST buffer when configured in RC mode;
analog otherwise.
CMOS
External clock source input. Always associated with
pin function, OSC1. (See related OSC1/CLKI,
OSC2/CLKO pins.)
TTL
General purpose I/O pin.
ST
31
O
—
CLKO
O
—
RA6
I/O
TTL
Oscillator crystal or clock output.
Oscillator crystal output. Connects to crystal
or resonator in Crystal Oscillator mode.
In RC mode, OSC2 pin outputs CLKO, which
has 1/4 the frequency of OSC1 and denotes
the instruction cycle rate.
General purpose I/O pin.
Legend: TTL = TTL compatible input
CMOS = CMOS compatible input or output
ST = Schmitt Trigger input with CMOS levels
I
= Input
O
= Output
P
= Power
I2C = I2C™/SMBus
Note 1: Default assignment for CCP2 when Configuration bit, CCP2MX, is set.
2: Alternate assignment for CCP2 when Configuration bit, CCP2MX, is cleared.
DS39755C-page 18
© 2009 Microchip Technology Inc.
PIC18F2423/2523/4423/4523
TABLE 1-3:
PIC18F4423/4523 PINOUT I/O DESCRIPTIONS (CONTINUED)
Pin Name
Pin Number
PDIP
Pin Buffer
QFN TQFP Type Type
Description
PORTA is a bidirectional I/O port.
RA0/AN0
RA0
AN0
2
RA1/AN1
RA1
AN1
3
RA2/AN2/VREF-/CVREF
RA2
AN2
VREFCVREF
4
RA3/AN3/VREF+
RA3
AN3
VREF+
5
RA4/T0CKI/C1OUT
RA4
T0CKI
C1OUT
6
RA5/AN4/SS/HLVDIN/
C2OUT
RA5
AN4
SS
HLVDIN
C2OUT
7
19
20
21
22
23
24
19
I/O
I
TTL
Analog
Digital I/O.
Analog Input 0.
I/O
I
TTL
Analog
Digital I/O.
Analog Input 1.
I/O
I
I
O
TTL
Analog
Analog
Analog
Digital I/O.
Analog Input 2.
A/D reference voltage (low) input.
Comparator reference voltage output.
I/O
I
I
TTL
Analog
Analog
Digital I/O.
Analog Input 3.
A/D reference voltage (high) input.
I/O
I
O
ST
ST
—
I/O
I
I
I
O
TTL
Analog
TTL
Analog
—
20
21
22
23
Digital I/O.
Timer0 external clock input.
Comparator 1 output.
24
Digital I/O.
Analog Input 4.
SPI slave select input.
High/Low-Voltage Detect input.
Comparator 2 output.
RA6
See the OSC2/CLKO/RA6 pin.
RA7
See the OSC1/CLKI/RA7 pin.
Legend: TTL = TTL compatible input
CMOS = CMOS compatible input or output
ST = Schmitt Trigger input with CMOS levels
I
= Input
O
= Output
P
= Power
I2C = I2C™/SMBus
Note 1: Default assignment for CCP2 when Configuration bit, CCP2MX, is set.
2: Alternate assignment for CCP2 when Configuration bit, CCP2MX, is cleared.
© 2009 Microchip Technology Inc.
DS39755C-page 19
PIC18F2423/2523/4423/4523
TABLE 1-3:
PIC18F4423/4523 PINOUT I/O DESCRIPTIONS (CONTINUED)
Pin Name
Pin Number
PDIP
Pin Buffer
QFN TQFP Type Type
Description
PORTB is a bidirectional I/O port. PORTB can be
software programmed for internal weak pull-ups on all
inputs.
RB0/INT0/FLT0/AN12
RB0
INT0
FLT0
AN12
33
RB1/INT1/AN10
RB1
INT1
AN10
34
RB2/INT2/AN8
RB2
INT2
AN8
35
RB3/AN9/CCP2
RB3
AN9
CCP2(1)
36
RB4/KBI0/AN11
RB4
KBI0
AN11
37
RB5/KBI1/PGM
RB5
KBI1
PGM
38
RB6/KBI2/PGC
RB6
KBI2
PGC
39
RB7/KBI3/PGD
RB7
KBI3
PGD
40
9
10
11
12
14
15
16
17
8
I/O
I
I
I
TTL
ST
ST
Analog
Digital I/O.
External Interrupt 0.
PWM Fault input for Enhanced CCP1.
Analog Input 12.
I/O
I
I
TTL
ST
Analog
Digital I/O.
External Interrupt 1.
Analog Input 10.
I/O
I
I
TTL
ST
Analog
Digital I/O.
External Interrupt 2.
Analog Input 8.
I/O
I
I/O
TTL
Analog
ST
Digital I/O.
Analog Input 9.
Capture 2 input/Compare 2 output/PWM2 output.
I/O
I
I
TTL
TTL
Analog
Digital I/O.
Interrupt-on-change pin.
Analog Input 11.
I/O
I
I/O
TTL
TTL
ST
Digital I/O.
Interrupt-on-change pin.
Low-Voltage ICSP™ Programming enable pin.
I/O
I
I/O
TTL
TTL
ST
Digital I/O.
Interrupt-on-change pin.
In-Circuit Debugger and ICSP programming
clock pin.
I/O
I
I/O
TTL
TTL
ST
Digital I/O.
Interrupt-on-change pin.
In-Circuit Debugger and ICSP programming
data pin.
9
10
11
14
15
16
17
Legend: TTL = TTL compatible input
CMOS = CMOS compatible input or output
ST = Schmitt Trigger input with CMOS levels
I
= Input
O
= Output
P
= Power
I2C = I2C™/SMBus
Note 1: Default assignment for CCP2 when Configuration bit, CCP2MX, is set.
2: Alternate assignment for CCP2 when Configuration bit, CCP2MX, is cleared.
DS39755C-page 20
© 2009 Microchip Technology Inc.
PIC18F2423/2523/4423/4523
TABLE 1-3:
PIC18F4423/4523 PINOUT I/O DESCRIPTIONS (CONTINUED)
Pin Name
Pin Number
PDIP
Pin Buffer
QFN TQFP Type Type
Description
PORTC is a bidirectional I/O port.
RC0/T1OSO/T13CKI
RC0
T1OSO
T13CKI
15
RC1/T1OSI/CCP2
RC1
T1OSI
CCP2(2)
16
RC2/CCP1/P1A
RC2
CCP1
P1A
17
RC3/SCK/SCL
RC3
SCK
18
34
35
36
37
32
23
RC5/SDO
RC5
SDO
24
RC6/TX/CK
RC6
TX
CK
25
RC7/RX/DT
RC7
RX
DT
26
42
43
44
1
ST
—
ST
Digital I/O.
Timer1 oscillator output.
Timer1/Timer3 external clock input.
I/O
I
I/O
ST
CMOS
ST
Digital I/O.
Timer1 oscillator input.
Capture 2 input/Compare 2 output/PWM2 output.
I/O
I/O
O
ST
ST
—
Digital I/O.
Capture 1 input/Compare 1 output/PWM1 output.
Enhanced CCP1 output.
I/O
I/O
ST
ST
I/O
I2C
Digital I/O.
Synchronous serial clock input/output for
SPI mode.
Synchronous serial clock input/output for I2C™ mode.
I/O
I
I/O
ST
ST
I2C
Digital I/O.
SPI data in.
I2C data I/O.
I/O
O
ST
—
Digital I/O.
SPI data out.
I/O
O
I/O
ST
—
ST
Digital I/O.
EUSART asynchronous transmit.
EUSART synchronous clock (see related RX/DT).
I/O
I
I/O
ST
ST
ST
Digital I/O.
EUSART asynchronous receive.
EUSART synchronous data (see related TX/CK).
35
36
37
SCL
RC4/SDI/SDA
RC4
SDI
SDA
I/O
O
I
42
43
44
1
Legend: TTL = TTL compatible input
CMOS = CMOS compatible input or output
ST = Schmitt Trigger input with CMOS levels
I
= Input
O
= Output
P
= Power
I2C = I2C™/SMBus
Note 1: Default assignment for CCP2 when Configuration bit, CCP2MX, is set.
2: Alternate assignment for CCP2 when Configuration bit, CCP2MX, is cleared.
© 2009 Microchip Technology Inc.
DS39755C-page 21
PIC18F2423/2523/4423/4523
TABLE 1-3:
Pin Name
PIC18F4423/4523 PINOUT I/O DESCRIPTIONS (CONTINUED)
Pin Number
PDIP
Pin Buffer
QFN TQFP Type Type
Description
PORTD is a bidirectional I/O port or a Parallel Slave
Port (PSP) for interfacing to a microprocessor port.
These pins have TTL input buffers when the PSP
module is enabled.
RD0/PSP0
RD0
PSP0
19
RD1/PSP1
RD1
PSP1
20
RD2/PSP2
RD2
PSP2
21
RD3/PSP3
RD3
PSP3
22
RD4/PSP4
RD4
PSP4
27
RD5/PSP5/P1B
RD5
PSP5
P1B
28
RD6/PSP6/P1C
RD6
PSP6
P1C
29
RD7/PSP7/P1D
RD7
PSP7
P1D
30
38
39
40
41
2
3
4
5
38
I/O
I/O
ST
TTL
Digital I/O.
Parallel Slave Port data.
I/O
I/O
ST
TTL
Digital I/O.
Parallel Slave Port data.
I/O
I/O
ST
TTL
Digital I/O.
Parallel Slave Port data.
I/O
I/O
ST
TTL
Digital I/O.
Parallel Slave Port data.
I/O
I/O
ST
TTL
Digital I/O.
Parallel Slave Port data.
I/O
I/O
O
ST
TTL
—
Digital I/O.
Parallel Slave Port data.
Enhanced CCP1 output.
I/O
I/O
O
ST
TTL
—
Digital I/O.
Parallel Slave Port data.
Enhanced CCP1 output.
I/O
I/O
O
ST
TTL
—
Digital I/O.
Parallel Slave Port data.
Enhanced CCP1 output.
39
40
41
2
3
4
5
Legend: TTL = TTL compatible input
CMOS = CMOS compatible input or output
ST = Schmitt Trigger input with CMOS levels
I
= Input
O
= Output
P
= Power
I2C = I2C™/SMBus
Note 1: Default assignment for CCP2 when Configuration bit, CCP2MX, is set.
2: Alternate assignment for CCP2 when Configuration bit, CCP2MX, is cleared.
DS39755C-page 22
© 2009 Microchip Technology Inc.
PIC18F2423/2523/4423/4523
TABLE 1-3:
Pin Name
PIC18F4423/4523 PINOUT I/O DESCRIPTIONS (CONTINUED)
Pin Number
PDIP
Pin Buffer
QFN TQFP Type Type
Description
PORTE is a bidirectional I/O port.
RE0/RD/AN5
RE0
RD
8
25
25
AN5
RE1/WR/AN6
RE1
WR
9
26
10
27
—
I
Analog
I/O
I
ST
TTL
I
Analog
I/O
I
ST
TTL
I
Analog
Digital I/O.
Read control for Parallel Slave Port
(see also WR and CS pins).
Analog Input 5.
Digital I/O.
Write control for Parallel Slave Port
(see CS and RD pins).
Analog Input 6.
27
AN7
RE3
ST
TTL
26
AN6
RE2/CS/AN7
RE2
CS
I/O
I
Digital I/O.
Chip select control for Parallel Slave Port
(see related RD and WR).
Analog Input 7.
—
—
—
See MCLR/VPP/RE3 pin.
6, 29
P
—
Ground reference for logic and I/O pins.
7, 8, 7, 28
28, 29
P
—
Positive supply for logic and I/O pins.
—
—
No connect.
—
VSS
12, 31 6, 30,
31
VDD
11, 32
NC
—
13
12, 13,
33, 34
Legend: TTL = TTL compatible input
CMOS = CMOS compatible input or output
ST = Schmitt Trigger input with CMOS levels
I
= Input
O
= Output
P
= Power
I2C = I2C™/SMBus
Note 1: Default assignment for CCP2 when Configuration bit, CCP2MX, is set.
2: Alternate assignment for CCP2 when Configuration bit, CCP2MX, is cleared.
© 2009 Microchip Technology Inc.
DS39755C-page 23
PIC18F2423/2523/4423/4523
NOTES:
DS39755C-page 24
© 2009 Microchip Technology Inc.
PIC18F2423/2523/4423/4523
2.0
12-BIT ANALOG-TO-DIGITAL
CONVERTER (A/D) MODULE
The Analog-to-Digital (A/D) Converter module has
10 inputs for the PIC18F2423/2523 devices and 13 for
the PIC18F4423/4523 devices. This module allows
conversion of an analog input signal to a corresponding
12-bit digital number.
The module has five registers:
•
•
•
•
•
Of the ADCONx registers:
• ADCON0 (shown in Register 2-1) – Controls the
module’s operation
• ADCON1 (Register 2-2) – Configures the
functions of the port pins
• ADCON2 (Register 2-3) – Configures the A/D
clock source, programmed acquisition time and
justification
A/D Result High Register (ADRESH)
A/D Result Low Register (ADRESL)
A/D Control Register 0 (ADCON0)
A/D Control Register 1 (ADCON1)
A/D Control Register 2 (ADCON2)
REGISTER 2-1:
ADCON0: A/D CONTROL REGISTER 0
U-0
U-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
—
—
CHS3
CHS2
CHS1
CHS0
GO/DONE
ADON
bit 7
bit 0
Legend:
R = Readable bit
W = Writable bit
U = Unimplemented bit, read as ‘0’
-n = Value at POR
‘1’ = Bit is set
‘0’ = Bit is cleared
bit 7-6
Unimplemented: Read as ‘0’
bit 5-2
CHS: Analog Channel Select bits
0000 = Channel 0 (AN0)
0001 = Channel 1 (AN1)
0010 = Channel 2 (AN2)
0011 = Channel 3 (AN3)
0100 = Channel 4 (AN4)
0101 = Channel 5 (AN5)(1,2)
0110 = Channel 6 (AN6)(1,2)
0111 = Channel 7 (AN7)(1,2)
1000 = Channel 8 (AN8)
1001 = Channel 9 (AN9)
1010 = Channel 10 (AN10)
1011 = Channel 11 (AN11)
1100 = Channel 12 (AN12
1101 = Unimplemented(2)
1110 = Unimplemented(2)
1111 = Unimplemented(2)
bit 1
GO/DONE: A/D Conversion Status bit
When ADON = 1:
1 = A/D conversion in progress
0 = A/D Idle
bit 0
ADON: A/D On bit
1 = A/D Converter module is enabled
0 = A/D Converter module is disabled
Note 1:
2:
x = Bit is unknown
These channels are not implemented on PIC18F2423/2523 devices.
Performing a conversion on unimplemented channels will return a floating input measurement.
© 2009 Microchip Technology Inc.
DS39755C-page 25
PIC18F2423/2523/4423/4523
REGISTER 2-2:
ADCON1: A/D CONTROL REGISTER 1
U-0
U-0
R/W-0
R/W-0
R/W-0(1)
R/W(1)
R/W(1)
R/W(1)
—
—
VCFG1
VCFG0
PCFG3
PCFG2
PCFG1
PCFG0
bit 7
bit 0
Legend:
R = Readable bit
W = Writable bit
U = Unimplemented bit, read as ‘0’
-n = Value at POR
‘1’ = Bit is set
‘0’ = Bit is cleared
AN2
AN1
AN0
0111(1)
1000
1001
1010
1011
1100
1101
1110
1111
AN3
0000(1)
0001
0010
0011
0100
0101
0110
AN4
PCFG
AN5(2)
PCFG: A/D Port Configuration Control bits:
AN6(2)
bit 3-0
AN7(2)
VCFG0: Voltage Reference Configuration bit (VREF+ source)
1 = VREF+ (AN3)
0 = VDD
AN8
bit 4
AN9
VCFG1: Voltage Reference Configuration bit (VREF- source)
1 = VREF- (AN2)
0 = VSS
AN10
bit 5
AN11
Unimplemented: Read as ‘0’
AN12
bit 7-6
A
A
A
D
D
D
D
D
A
A
A
A
D
D
D
D
A
A
A
A
A
D
D
D
A
A
A
A
A
A
D
D
A
A
A
A
A
A
A
D
A
A
A
A
A
A
A
A
A
A
A
A
A
A
A
A
A
A
A
A
A
A
A
A
A
A
A
A
A
A
A
A
A
A
A
A
A
A
A
A
A
A
A
A
A
A
A
A
A
A
A
A
A
A
A
A
A
A
A
A
A
A
A
A
D
D
D
D
D
D
D
D
D
D
D
D
D
D
D
D
D
D
D
D
D
D
D
D
D
D
D
D
D
D
D
D
D
D
D
D
D
D
D
D
D
D
D
D
D
D
D
D
A
D
D
D
D
D
D
D
A
A
D
D
D
D
D
D
A
A
A
D
D
D
D
D
A
A
A
A
D
D
D
D
A
A
A
A
A
D
D
D
A
A
A
A
A
A
D
D
A
A
A
A
A
A
A
D
A = Analog input
Note 1:
2:
x = Bit is unknown
D = Digital I/O
The POR value of the PCFG bits depends on the value of the PBADEN Configuration bit. When
PBADEN = 1, PCFG = 0000; when PBADEN = 0, PCFG = 0111.
AN5 through AN7 are only available on PIC18F4423/4523 devices.
DS39755C-page 26
© 2009 Microchip Technology Inc.
PIC18F2423/2523/4423/4523
REGISTER 2-3:
ADCON2: A/D CONTROL REGISTER 2
R/W-0
U-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
ADFM
—
ACQT2
ACQT1
ACQT0
ADCS2
ADCS1
ADCS0
bit 7
bit 0
Legend:
R = Readable bit
W = Writable bit
U = Unimplemented bit, read as ‘0’
-n = Value at POR
‘1’ = Bit is set
‘0’ = Bit is cleared
bit 7
ADFM: A/D Result Format Select bit
1 = Right justified
0 = Left justified
bit 6
Unimplemented: Read as ‘0’
bit 5-3
ACQT: A/D Acquisition Time Select bits
111 = 20 TAD
110 = 16 TAD
101 = 12 TAD
100 = 8 TAD
011 = 6 TAD
010 = 4 TAD
001 = 2 TAD
000 = 0 TAD(1)
bit 2-0
ADCS: A/D Conversion Clock Select bits
111 = FRC (clock derived from A/D RC oscillator)(1)
110 = FOSC/64
101 = FOSC/16
100 = FOSC/4
011 = FRC (clock derived from A/D RC oscillator)(1)
010 = FOSC/32
001 = FOSC/8
000 = FOSC/2
Note 1:
x = Bit is unknown
If the A/D FRC clock source is selected, a delay of one TCY (instruction cycle) is added before the A/D
clock starts. This allows the SLEEP instruction to be executed before starting a conversion.
© 2009 Microchip Technology Inc.
DS39755C-page 27
PIC18F2423/2523/4423/4523
The analog reference voltage is software selectable to
either the device’s positive and negative supply voltage
(VDD and VSS), or the voltage level on the RA3/AN3/
VREF+ and RA2/AN2/VREF-/CVREF pins.
A device Reset forces all registers to their Reset state.
This forces the A/D module to be turned off and any
conversion in progress is aborted.
Each port pin associated with the A/D Converter can be
configured as an analog input or as a digital I/O. The
ADRESH and ADRESL registers contain the result of
the A/D conversion. When the A/D conversion is complete, the result is loaded into the ADRESH:ADRESL
register pair, the GO/DONE bit (ADCON0) is cleared
and A/D Interrupt Flag bit, ADIF, is set.
The A/D Converter has a unique feature of being able
to operate while the device is in Sleep mode. To operate in Sleep, the A/D conversion clock must be derived
from the A/D’s internal RC oscillator.
The output of the sample and hold is the input into the
converter, which generates the result via successive
approximation.
FIGURE 2-1:
The block diagram of the A/D module is shown in
Figure 2-1.
A/D BLOCK DIAGRAM
CHS
1100
1011
1010
1001
1000
0111
0110
0101
0100
12-Bit
A/D
Converter
VAIN
(Input Voltage)
0011
0010
0001
VCFG
VDD(2)
Reference
Voltage
VREF+
X0
X1
VREF-
1X
0X
0000
AN12
AN11
AN10
AN9
AN8
AN7(1)
AN6(1)
AN5(1)
AN4
AN3
AN2
AN1
AN0
VSS(2)
Note 1:
2:
Channels, AN5 through AN7, are not available on PIC18F2423/2523 devices.
I/O pins have diode protection to VDD and VSS.
DS39755C-page 28
© 2009 Microchip Technology Inc.
PIC18F2423/2523/4423/4523
Wait for the A/D conversion to complete by either:
• Polling for the GO/DONE bit to be cleared
OR
• Waiting for the A/D interrupt
Read the A/D Result registers (ADRESH:ADRESL)
and clear the ADIF bit, if required.
For the next conversion, go to step 1 or step 2,
as required.
6.
7.
The A/D conversion time per bit is defined as
TAD. A minimum wait of 2 TAD is required before
the next acquisition starts.
After this acquisition time has elapsed, the A/D conversion can be started. An acquisition time can be
programmed to occur between setting the GO/DONE
bit and the actual start of the conversion.
FFFh
FFEh
003h
002h
001h
4095 LSB
4095.5 LSB
4094 LSB
4094.5 LSB
3 LSB
000h
2 LSB
3.
4.
A/D TRANSFER FUNCTION
2.5 LSB
2.
Configure the A/D module:
• Configure analog pins, voltage reference and
digital I/O (ADCON1)
• Select A/D input channel (ADCON0)
• Select A/D acquisition time (ADCON2)
• Select A/D conversion clock (ADCON2)
• Turn on the A/D module (ADCON0)
Configure the A/D interrupt (if desired):
• Clear ADIF bit
• Set ADIE bit
• Set GIE bit
Wait the required acquisition time (if required).
Start conversion by setting the GO/DONE bit
(ADCON0).
0.5 LSB
1.
FIGURE 2-2:
Digital Code Output
The following steps should be followed to perform an A/D
conversion:
1 LSB
After the A/D module has been configured as desired,
the selected channel must be acquired before the
conversion is started. The analog input channels must
have their corresponding TRIS bits selected as inputs.
To determine acquisition time, see Section 2.1 “A/D
Acquisition Requirements”.
5.
1.5 LSB
The value in the ADRESH:ADRESL registers is
unknown following POR and BOR Resets and is not
affected by any other Reset.
Analog Input Voltage
FIGURE 2-3:
ANALOG INPUT MODEL
VDD
Rs
VAIN
Sampling
Switch
VT = 0.6V
ANx
RIC ≤ 1k
CPIN
5 pF
VT = 0.6V
SS
RSS
CHOLD = 25 pF
ILEAKAGE
±100 nA
VSS
Legend: CPIN
= Input Capacitance
VT
= Threshold Voltage
ILEAKAGE = Leakage Current at the pin due to
various junctions
= Interconnect Resistance
RIC
= Sampling Switch
SS
= Sample/Hold Capacitance (from DAC)
CHOLD
RSS
= Sampling Switch Resistance
© 2009 Microchip Technology Inc.
VDD
6V
5V
4V
3V
2V
1
2 3
4
Sampling Switch (kΩ)
DS39755C-page 29
PIC18F2423/2523/4423/4523
2.1
A/D Acquisition Requirements
For the A/D Converter to meet its specified accuracy,
the charge holding capacitor (CHOLD) must be allowed
to fully charge to the input channel voltage level. The
analog input model is shown in Figure 2-3.
The source impedance (RS) and the internal sampling
switch (RSS) impedance directly affect the time
required to charge the capacitor, CHOLD. The sampling
switch (RSS) impedance varies over the device voltage
(VDD). The source impedance affects the offset voltage
at the analog input (due to pin leakage current). The
maximum recommended impedance for analog
sources is 2.5 kΩ.
After the analog input channel is selected (changed),
the channel must be sampled for at least the minimum
acquisition time before starting a conversion.
Note:
TABLE 2-1:
TACQ ASSUMPTIONS
CHOLD
=
25 pF
Rs
=
2.5 kΩ
Conversion Error
≤
1/2 LSb
VDD
=
3V → Rss = 4 kΩ
Temperature
=
85°C (system maximum)
ACQUISITION TIME
=
Amplifier Settling Time + Holding Capacitor Charging Time + Temperature Coefficient
=
TAMP + TC + TCOFF
EQUATION 2-2:
VHOLD
or
TC
Example 2-3 shows the calculation of the minimum
required acquisition time, TACQ. This calculation is
based on the application system assumptions shown in
Table 2-1:
When the conversion is started, the
holding capacitor is disconnected from the
input pin.
EQUATION 2-1:
TACQ
To calculate the minimum acquisition time, Equation 2-1
may be used. This equation assumes that 1/2 LSb error
is used (4,096 steps for the A/D). The 1/2 LSb error is the
maximum error allowed for the A/D to meet its specified
resolution.
A/D MINIMUM CHARGING TIME
=
(VREF – (VREF/4096)) • (1 – e(-TC/CHOLD(RIC + RSS + RS)))
=
-(CHOLD)(RIC + RSS + RS) ln(1/4096)
EQUATION 2-3:
CALCULATING THE MINIMUM REQUIRED ACQUISITION TIME
TACQ
=
TAMP + TC + TCOFF
TAMP
=
0.2 μs
TCOFF
=
(Temp – 25°C)(0.02 μs/°C)
(85°C – 25°C)(0.02 μs/°C)
1.2 μs
Temperature coefficient is only required for temperatures > 25°C. Below 25°C, TCOFF = 0 ms.
TC
=
-(CHOLD)(RIC + RSS + RS) ln(1/4095) μs
-(25 pF) (1 kΩ + 4 kΩ + 2.5 kΩ) ln(0.0004883) μs
1.56 μs
TACQ
=
0.2 μs + 1.56 μs + 1.2 μs
2.96 μs
DS39755C-page 30
© 2009 Microchip Technology Inc.
PIC18F2423/2523/4423/4523
2.2
Selecting and Configuring
Acquisition Time
2.3
Selecting the A/D Conversion
Clock
The ADCON2 register allows the user to select an
acquisition time that occurs each time the GO/DONE
bit is set. It also gives users the option of having an
automatically determined acquisition time.
The A/D conversion time per bit is defined as TAD. The
A/D conversion requires 13 TAD per 12-bit conversion.
The source of the A/D conversion clock is software
selectable.
Acquisition time may be set with the ACQT bits
(ADCON2), which provide a range of 2 to 20 TAD.
When the GO/DONE bit is set, the A/D module continues to sample the input for the selected acquisition
time, then automatically begins a conversion. Since the
acquisition time is programmed, there may be no need
to wait for an acquisition time between selecting a
channel and setting the GO/DONE bit.
There are seven possible options for TAD:
• 2 TOSC
• 32 TOSC
• 4 TOSC
• 64 TOSC
• 8 TOSC
• Internal RC Oscillator
• 16 TOSC
For correct A/D conversions, the A/D conversion clock
(TAD) must be as short as possible, but greater than the
minimum TAD. (For more information, see parameter 130
on page 41.)
Manual acquisition time is selected when
ACQT = 000. When the GO/DONE bit is set,
sampling is stopped and a conversion begins. The user
is responsible for ensuring the required acquisition time
has passed between selecting the desired input
channel and setting the GO/DONE bit. This option is
also the default Reset state of the ACQT bits and
is compatible with devices that do not offer
programmable acquisition times.
Table 2-2 shows the resultant TAD times derived from
the device operating frequencies and the A/D clock
source selected.
In either case, when the conversion is completed, the
GO/DONE bit is cleared, the ADIF flag is set and the
A/D begins sampling the currently selected channel
again. If an acquisition time is programmed, there is
nothing to indicate if the acquisition time has ended or
if the conversion has begun.
TABLE 2-2:
TAD vs. DEVICE OPERATING FREQUENCIES
Assumes TAD Min. = 0.8 μs
A/D Clock Source (TAD)
Note 1:
2:
Operation
ADCS
Maximum FOSC
2 TOSC
000
2.50 MHz
4 TOSC
100
5.00 MHz
8 TOSC
001
10.00 MHz
16 TOSC
101
20.00 MHz
32 TOSC
010
40.00 MHz
64 TOSC
110
40.00 MHz
RC(2)
x11
1.00 MHz(1)
The RC source has a typical TAD time of 2.5 μs.
For device frequencies above 1 MHz, the device must be in Sleep for the entire conversion or a FOSC
divider should be used instead; otherwise, the A/D accuracy specification may not be met.
© 2009 Microchip Technology Inc.
DS39755C-page 31
PIC18F2423/2523/4423/4523
2.4
Operation in Power-Managed
Modes
The selection of the automatic acquisition time and A/D
conversion clock is determined in part by the clock
source and frequency while in a power-managed mode.
If the A/D is expected to operate while the device is in
a power-managed mode, the ADCS bits in
ADCON2 should be updated in accordance with the
clock source to be used. The ACQT bits do not
need to be adjusted as the ADCS bits adjust the
TAD time for the new clock speed. After entering the
mode, an A/D acquisition or conversion may be started.
Once started, the device should continue to be clocked
by the same clock source until the conversion has been
completed.
If desired, the device may be placed into the
corresponding Idle mode during the conversion. If the
device clock frequency is less than 1 MHz, the A/D RC
clock source should be selected.
Operation in Sleep mode requires the A/D FRC clock to
be selected. If bits, ACQT, are set to ‘000’ and a
conversion is started, the conversion will be delayed
one instruction cycle to allow execution of the SLEEP
instruction and entry to Sleep mode. The IDLEN bit
(OSCCON) must have already been cleared prior
to starting the conversion.
DS39755C-page 32
2.5
Configuring Analog Port Pins
The ADCON1, TRISA, TRISB and TRISE registers all
configure the A/D port pins. The port pins needed as
analog inputs must have their corresponding TRIS bits
set (input). If the TRIS bit is cleared (output), the digital
output level (VOH or VOL) will be converted.
The A/D operation is independent of the state of the
CHS bits and the TRIS bits.
Note 1: When reading the PORT register, all pins
configured as analog input channels will
read as cleared (a low level). Analog conversion on pins configured as digital pins
can be performed. The voltage on the pin
will be accurately converted.
2: Analog levels on any pin defined as a
digital input may cause the digital input
buffer to consume current out of the
device’s specification limits.
3: The PBADEN bit in Configuration
Register 3H configures PORTB pins to
reset as analog or digital pins by controlling
how the PCFG bits in ADCON1 are
reset.
© 2009 Microchip Technology Inc.
PIC18F2423/2523/4423/4523
2.6
A/D Conversions
After the A/D conversion is completed or aborted, a
2 TCY wait is required before the next acquisition can
be started. After this wait, acquisition on the selected
channel is automatically started.
Figure 2-4 shows the operation of the A/D Converter
after the GO/DONE bit has been set and the
ACQT bits are cleared. A conversion is started
after the following instruction to allow entry into Sleep
mode before the conversion begins.
Note:
Figure 2-5 shows the operation of the A/D Converter
after the GO/DONE bit has been set, the ACQT
bits have been set to ‘010’ and a 4 TAD acquisition time
has been selected before the conversion starts.
2.7
Clearing the GO/DONE bit during a conversion will abort
the current conversion. The A/D Result register pair will
NOT be updated with the partially completed A/D
conversion sample. This means, the ADRESH:ADRESL
registers will continue to contain the value of the last
completed conversion (or the last value written to the
ADRESH:ADRESL registers).
FIGURE 2-4:
The GO/DONE bit should NOT be set in
the same instruction that turns on the A/D.
Code should wait at least 3 TAD after
enabling the A/D before beginning an
acquisition and conversion cycle.
Discharge
The discharge phase is used to initialize the value of
the holding capacitor. The array is discharged before
every sample. This feature helps to optimize the unitygain amplifier, as the circuit always needs to charge the
capacitor array, rather than charge/discharge based on
previous measure values.
A/D CONVERSION TAD CYCLES (ACQT = 000, TACQ = 0)
TCY – TAD TAD1 TAD2 TAD3 TAD4 TAD5 TAD6 TAD7 TAD8 TAD9 TAD10 TAD11 TAD12 TAD13 TAD1
b11
b10
b9
b8
b7
b6
b3
b4
b5
b2
b1
b0
Conversion starts
Discharge
(typically 200 ns)
Holding capacitor is disconnected from analog input (typically 100 ns)
Set GO/DONE bit
On the following cycle:
ADRESH:ADRESL are loaded, GO/DONE bit is cleared,
ADIF bit is set, holding capacitor is connected to analog input.
A/D CONVERSION TAD CYCLES (ACQT = 010, TACQ = 4 TAD)
FIGURE 2-5:
TAD Cycles
TACQT Cycles
1
2
3
4
1
Automatic
Acquisition
Time
Set GO/DONE bit
(Holding capacitor continues
acquiring input)
© 2009 Microchip Technology Inc.
2
b11
3
b10
4
b9
5
b8
6
b7
7
b6
8
b5
9
b4
10
b3
11
b2
12
b1
13
b0
TAD1
Discharge
(typically
200 ns)
Conversion starts
(Holding capacitor is disconnected)
Points to end of TACQT period (current black arrow)
On the following cycle:
ADRESH:ADRESL are loaded, GO/DONE bit is cleared,
ADIF bit is set, holding capacitor is connected to analog input.
DS39755C-page 33
PIC18F2423/2523/4423/4523
2.8
Use of the CCP2 Trigger
An A/D conversion can be started by the Special Event
Trigger of the CCP2 module. This requires that the
CCP2M bits (CCP2CON) be programmed
as ‘1011’ and that the A/D module is enabled (ADON
bit is set). When the trigger occurs, the GO/DONE bit
will be set, starting the A/D acquisition and conversion,
and the Timer1 (or Timer3) counter will be reset to zero.
Timer1 (or Timer3) is reset to automatically repeat the
A/D acquisition period with minimal software overhead
(moving ADRESH:ADRESL to the desired location).
TABLE 2-3:
Name
The appropriate analog input channel must be selected
and the minimum acquisition period is either timed by
the user or an appropriate TACQ time is selected before
the Special Event Trigger sets the GO/DONE bit (starts
a conversion).
If the A/D module is not enabled (ADON is cleared), the
Special Event Trigger will be ignored by the A/D
module, but will still reset the Timer1 (or Timer3)
counter.
REGISTERS ASSOCIATED WITH A/D OPERATION
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Reset
Values on
page
INTCON
GIE/GIEH PEIE/GIEL TMR0IE
INT0IE
RBIE
TMR0IF
INT0IF
RBIF
(Note 4)
PIR1
PSPIF(1)
ADIF
RCIF
TXIF
SSPIF
CCP1IF
TMR2IF
TMR1IF
(Note 4)
PIE1
PSPIE(1)
ADIE
RCIE
TXIE
SSPIE
CCP1IE
TMR2IE
TMR1IE
(Note 4)
IPR1
PSPIP(1)
ADIP
RCIP
TXIP
SSPIP
CCP1IP
TMR2IP
TMR1IP
(Note 4)
PIR2
OSCFIF
CMIF
—
EEIF
BCLIF
HLVDIF
TMR3IF
CCP2IF
(Note 4)
PIE2
OSCFIE
CMIE
—
EEIE
BCLIE
HLVDIE
TMR3IE
CCP2IE
(Note 4)
OSCFIP
CMIP
—
EEIP
BCLIP
HLVDIP
TMR3IP
CCP2IP
(Note 4)
IPR2
ADRESH
A/D Result Register High Byte
(Note 4)
ADRESL
A/D Result Register Low Byte
(Note 4)
ADCON0
—
—
CHS3
CHS2
CHS1
CHS0
GO/DONE
ADON
(Note 4)
ADCON1
—
—
VCFG1
VCFG0
PCFG3
PCFG2
PCFG1
PCFG0
(Note 4)
(Note 4)
ADCON2
ADFM
—
ACQT2
ACQT1
ACQT0
ADCS2
ADCS1
ADCS0
PORTA
RA7(2)
RA6(2)
RA5
RA4
RA3
RA2
RA1
RA0
(2)
TRISA
TRISA7
PORTB
RB7
TRISA6(2) PORTA Data Direction Control Register
RB6
RB5
RB4
RB3
RB2
TRISB
PORTB Data Direction Control Register
LATB
PORTB Data Latch Register (Read and Write to Data Latch)
(1)
(Note 4)
(Note 4)
RB1
RB0
(Note 4)
(Note 4)
RE3
(3)
PORTE
—
—
—
—
TRISE(1)
IBF
OBF
IBOV
PSPMODE
—
LATE(1)
—
—
—
—
—
(Note 4)
RE2
RE1
RE0
(Note 4)
TRISE2
TRISE1
TRISE0
(Note 4)
PORTE Data Latch Register
(Note 4)
Legend: — = unimplemented, read as ‘0’. Shaded cells are not used for A/D conversion.
Note 1: These registers and/or bits are not implemented on PIC18F2423/2523 devices and are read as ‘0’.
2: PORTA and their direction bits are individually configured as port pins based on various primary
oscillator modes. When disabled, these bits read as ‘0’.
3: RE3 port bit is available only as an input pin when the MCLRE Configuration bit is ‘0’.
4: For these Reset values, see Section 4.0 “Reset” of the “PIC18F2420/2520/4420/4520 Data Sheet”
(DS39631).
DS39755C-page 34
© 2009 Microchip Technology Inc.
PIC18F2423/2523/4423/4523
3.0
SPECIAL FEATURES OF THE
CPU
Note:
3.1
For additional details on the Configuration
bits, refer to Section 23.1 “Configuration
Bits” in the “PIC18F2420/2520/4420/4520
Data Sheet” (DS39631). Device ID information presented in this section is for the
PIC18F2423/2523/4423/4523 devices only.
TABLE 3-1:
Device ID Registers
The Device ID registers are read-only registers. They
identify the device type and revision for device programmers and can be read by firmware using table
reads.
DEVICE IDs
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Default/
Unprogrammed
Value
DEV3
DEV2
DEV1
DEV0
REV3
REV2
REV1
REV0
xxxx xxxx(2)
DEV11
DEV10
DEV9
DEV8
DEV7
DEV6
DEV5
DEV4
xxxx xxxx(2)
File Name
3FFFFEh DEVID1(1)
(1)
3FFFFFh
DEVID2
Legend:
Note 1:
2:
x = unknown, u = unchanged, — = unimplemented. Shaded cells are unimplemented, read as ‘0’.
DEVID registers are read-only and cannot be programmed by the user.
See Register 3-1 and Register 3-2 for DEVID1 and DEVID2 values.
REGISTER 3-1:
DEVID1: DEVICE ID REGISTER 1 FOR PIC18F2423/2523/4423/4523
R
R
R
R
R
R
R
R
DEV3
DEV2
DEV1
DEV0
REV3
REV2
REV1
REV0
bit 7
bit 0
Legend:
R = Read-only bit
P = Programmable bit
-n = Value when device is unprogrammed
U = Unimplemented bit, read as ‘0’
u = Unchanged from programmed state
bit 7-4
DEV: Device ID bits
1101 = PIC18F4423
1001 = PIC18F4523
0101 = PIC18F2423
0001 = PIC18F2523
bit 3-0
REV: Revision ID bits
These bits are used to indicate the device revision.
© 2009 Microchip Technology Inc.
DS39755C-page 35
PIC18F2423/2523/4423/4523
REGISTER 3-2:
R
DEV11
(1)
DEVID2: DEVICE ID REGISTER 2 FOR PIC18F2423/2523/4423/4523
R
R
R
R
R
R
R
DEV10(1)
DEV9(1)
DEV8(1)
DEV7(1)
DEV6(1)
DEV5(1)
DEV4(1)
bit 7
bit 0
Legend:
R = Read-only bit
P = Programmable bit
-n = Value when device is unprogrammed
bit 7-0
Note 1:
U = Unimplemented bit, read as ‘0’
u = Unchanged from programmed state
DEV: Device ID bits(1)
These bits are used with the DEV bits in Device ID Register 1 to identify the part number.
0001 0001 = PIC18F2423/2523 devices
0001 0000 = PIC18F4423/4523 devices
These values for DEV may be shared with other devices. The specific device is always identified by
using the entire DEV bit sequence.
DS39755C-page 36
© 2009 Microchip Technology Inc.
PIC18F2423/2523/4423/4523
4.0
Note:
ELECTRICAL CHARACTERISTICS
Other than some basic data, this section documents only the PIC18F2423/2523/4423/4523 devices’ specifications that differ from those of the PIC18F2420/2520/4420/4520 devices. For detailed information on the
electrical specifications shared by the PIC18F2423/2523/4423/4523 and PIC18F2420/2520/4420/4520
devices, see the “PIC18F2420/2520/4420/4520 Data Sheet” (DS39631).
Absolute Maximum Ratings(†)
Ambient temperature under bias.............................................................................................................-40°C to +125°C
Storage temperature .............................................................................................................................. -65°C to +150°C
Voltage on any pin with respect to VSS (except VDD and MCLR) ................................................... -0.3V to (VDD + 0.3V)
Voltage on VDD with respect to VSS ......................................................................................................... -0.3V to +7.5V
Voltage on MCLR with respect to VSS (Note 2) ......................................................................................... 0V to +13.25V
Total power dissipation (Note 1) ...............................................................................................................................1.0W
Maximum current out of VSS pin ...........................................................................................................................300 mA
Maximum current into VDD pin ..............................................................................................................................250 mA
Input clamp current, IIK (VI < 0 or VI > VDD)...................................................................................................................... ±20 mA
Output clamp current, IOK (VO < 0 or VO > VDD) .............................................................................................................. ±20 mA
Maximum output current sunk by any I/O pin..........................................................................................................25 mA
Maximum output current sourced by any I/O pin ....................................................................................................25 mA
Maximum current sunk by all ports .......................................................................................................................200 mA
Maximum current sourced by all ports ..................................................................................................................200 mA
Note 1: Power dissipation is calculated as follows:
Pdis = VDD x {IDD – ∑ IOH} + ∑ {(VDD – VOH) x IOH} + ∑(VOL x IOL)
2: Voltage spikes below VSS at the MCLR/VPP/RE3 pin, inducing currents greater than 80 mA, may cause
latch-up. Thus, a series resistor of 50-100Ω should be used when applying a “low” level to the MCLR/VPP/
RE3 pin, rather than pulling this pin directly to VSS.
† NOTICE: Stresses above those listed under “Absolute Maximum Ratings” may cause permanent damage to the
device. This is a stress rating only and functional operation of the device at those or any other conditions above those
indicated in the operation listings of this specification is not implied. Exposure to maximum rating conditions for
extended periods may affect device reliability.
© 2009 Microchip Technology Inc.
DS39755C-page 37
PIC18F2423/2523/4423/4523
FIGURE 4-1:
PIC18F2423/2523/4423/4523 VOLTAGE-FREQUENCY GRAPH (INDUSTRIAL)
6.0V
5.5V
Voltage
5.0V
PIC18F2423/2523/4423/4523
4.5V
4.2V
4.0V
3.5V
3.0V
2.5V
2.0V
40 MHz
Frequency
FIGURE 4-2:
PIC18F2423/2523/4423/4523 VOLTAGE-FREQUENCY GRAPH (EXTENDED)
6.0V
5.5V
Voltage
5.0V
PIC18F2423/2523/4423/4523
4.5V
4.2V
4.0V
3.5V
3.0V
2.5V
2.0V
25 MHz
Frequency
DS39755C-page 38
© 2009 Microchip Technology Inc.
PIC18F2423/2523/4423/4523
FIGURE 4-3:
PIC18LF2423/2523/4423/4523 VOLTAGE-FREQUENCY GRAPH (INDUSTRIAL)
6.0V
5.5V
Voltage
5.0V
4.5V
PIC18LF2423/2523/4423/4523
4.2V
4.0V
3.5V
3.0V
2.5V
2.0V
40 MHz
4 MHz
Frequency
FMAX = (16.36 MHz/V) (VDDAPPMIN – 2.0V) + 4 MHz
Note: VDDAPPMIN is the minimum voltage of the PIC® device in the application.
© 2009 Microchip Technology Inc.
DS39755C-page 39
PIC18F2423/2523/4423/4523
TABLE 4-1:
Param
No.
A/D CONVERTER CHARACTERISTICS: PIC18F2423/2523/4423/4523 (INDUSTRIAL)
PIC18LF2423/2523/4423/4523 (INDUSTRIAL)
Sym
Characteristic
Min
Typ
Max
Units
Conditions
ΔVREF ≥ 3.0V
A01
NR
Resolution
—
—
12
bit
A03
EIL
Integral Linearity Error
—
