MICROCHIP PIC18F2585, PIC18F2680, PIC18F4585, PIC18F4680 Technical data

PIC18F2585/2680/4585/4680
Data Sheet
28/40/44-Pin
Enhanced Flash Microcontrollers
with ECAN™ Technology, 10-Bit A/D
and nanoWatt Technology
© 2007 Microchip Technology Inc. Preliminary DS39625C
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.
Trademarks
The Microchip name and logo, the Microchip logo, Accuron, dsPIC, K
EELOQ, KEELOQ logo, microID, MPLAB, PIC,
PICmicro, PICSTART, PRO MATE, PowerSmart, rfPIC, and SmartShunt are registered trademarks of Microchip Technology Incorporated in the U.S.A. and other countries.
AmpLab, FilterLab, Linear Active Thermistor, Migratable Memory, MXDEV, MXLAB, PS logo, SEEVAL, SmartSensor 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, ECAN, ECONOMONITOR, FanSense, FlexROM, fuzzyLAB, In-Circuit Serial Programming, ICSP, ICEPIC, Mindi, MiWi, MPASM, MPLAB Certified logo, MPLIB, MPLINK, PICkit, PICDEM, PICDEM.net, PICLAB, PICtail, PowerCal, PowerInfo, PowerMate, PowerTool, REAL ICE, rfLAB, rfPICDEM, Select Mode, Smart Serial, SmartTel, Total Endurance, UNI/O, 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.
© 2007, 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 Mountain View, California. The Company’s quality system processes and procedures are for its PIC MCUs and dsPIC® DSCs, KEEL 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.
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code hopping devices, Serial
DS39625C-page ii Preliminary © 2007 Microchip Technology Inc.
®
PIC18F2585/2680/4585/4680
28/40/44-Pin Enhanced Flash Microcontrollers with
ECAN Technology, 10-Bit A/D and nanoWatt Technology

Power Managed Modes:

• Run: CPU on, peripherals on
• Idle: CPU off, peripherals on
• Sleep: CPU off, peripherals off
• Idle mode currents down to 5.8 μA typical
• Sleep mode currents down to 0.1 μA typical
• Timer1 Oscillator: 1.1 μA, 32 kHz, 2V
• Watchdog Timer: 2.1 μA
• Two-Speed Oscillator Start-up

Flexible Oscillator Structure:

• 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:
- 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

Special Microcontroller Features:

• C compiler optimized architecture with optional extended instruction set
• 100,000 erase/write cycle Enhanced Flash program memory typical
• 1,000,000 erase/write cycle Data EEPROM memory typical
• Flash/Data EEPROM Retention: > 40 years
• Self-programmable under software control
• Priority levels for interrupts
• 8 x 8 Single Cycle Hardware Multiplier
• Extended Watchdog Timer (WDT):
- Programmable period from 41 ms to 131s
• Single-Supply 5V In-Circuit Serial Programming™ (ICSP™) via two pins
• In-Circuit Debug (ICD) via two pins
• Wide operating voltage range: 2.0V to 5.5V

Peripheral Highlights:

• High current sink/source 25 mA/25 mA
• Three external interrupts
• One Capture/Compare/PWM (CCP1) module
• Enhanced Capture/Compare/PWM (ECCP1) module (40/44-pin devices only):
- One, two or four PWM outputs
- Selectable polarity
- Programmable dead time
- Auto-Shutdown and Auto-Restart
• Master Synchronous Serial Port (MSSP) module supporting 3-wire SPI (all 4 modes) and I Master and Slave modes
• Enhanced Addressable USART module:
- Supports RS-485, RS-232 and LIN 1.3
- RS-232 operation using internal oscillator
block (no external crystal required)
- Auto-Wake-up on Start bit
- Auto-Baud Detect
• 10-bit, up to 11-channel Analog-to-Digital Converter module (A/D), up to 100 Ksps
- Auto-acquisition capability
- Conversion available during Sleep
• Dual analog comparators with input multiplexing
2
C™

ECAN Module Features:

• Message bit rates up to 1 Mbps
• Conforms to CAN 2.0B ACTIVE Specification
• Fully backward compatible with PIC18XXX8 CAN modules
• Three modes of operation:
- Legacy, Enhanced Legacy, FIFO
• Three dedicated transmit buffers with prioritization
• Two dedicated receive buffers
• Six programmable receive/transmit buffers
• Three full 29-bit acceptance masks
• 16 full 29-bit acceptance filters w/ dynamic association
• DeviceNet™ data byte filter support
• Automatic remote frame handling
• Advanced error management features
Program Memory Data Memory
Device
PIC18F2585 48K 24576 3328 1024 28 8 1/0 Y Y 1 0 1/3 PIC18F2680 64K 32768 3328 1024 28 8 1/0 Y Y 1 0 1/3 PIC18F4585 48K 24576 3328 1024 44 11 1/1 Y Y 1 2 1/3 PIC18F4680 64K 32768 3328 1024 40/44 11 1/1 Y Y 1 2 1/3
© 2007 Microchip Technology Inc. Preliminary DS39625C-page 1
Flash
(bytes)
# Single-Word
Instructions
SRAM (bytes)
EEPROM
(bytes)
I/O
10-Bit
A/D (ch)
CCP1/
ECCP1
(PWM)
SPI
MSSP
Master
I
2
C™
Comp.
EUSART
Timers
8/16-bit
PIC18F2585/2680/4585/4680

Pin Diagrams

40-Pin PDIP
MCLR/VPP/RE3
RA0/AN0 RA1/AN1
RA2/AN2/V
RA3/AN3/V
RA4/T0CKI
RA5/AN4/SS
RC0/T1OSO/T13CKI
RA0/AN0/CV
RA3/AN3/V
RA5/AN4/SS
RE1/WR
RE2/CS
OSC1/CLKI/RA7
OSC2/CLKO/RA6
RC0/T1OSO/T13CKI
RD0/PSP0/C1IN+
RD1/PSP1/C1IN-
/HLVDIN
OSC1/CLKI/RA7
OSC2/CLKO/RA6
RC1/T1OSI
RC2/CCP1
RC3/SCK/SCL
MCLR/VPP/RE3
RA1/AN1
RA2/AN2/V
RC3/SCK/SCL
REF+
RA4/T0CKI
/HLVDIN
RE0/RD
/AN5 /AN6/C1OUT /AN7/C2OUT
RC1/T1OSI
RC2/CCP1
REF+
REF
REF-
V
DD
VSS
REF-
V
1 2 3 4 5 6 7
SS
8
9 10 11 12 13 14
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20
PIC18F4585
PIC18F2585
PIC18F4680
28 27 26 25 24 23 22 21 20 19 18 17 16 15
40 39 38 37 36 35 34 33 32 31 30 29 28 27 26 25 24 23 22 21
RB7/KBI3/PGD RB6/KBI2/PGC RB5/KBI1/PGM RB4/KBI0/AN9 RB3/CANRX RB2/INT2/CANTX RB1/INT1/AN8 RB0/INT0/AN10 V
DD
VSS RC7/RX/DT RC6/TX/CK RC5/SDO RC4/SDI/SDA
RB7/KBI3/PGD RB6/KBI2/PGC
RB5/KBI1/PGM RB4/KBI0/AN9 RB3/CANRX RB2/INT2/CANTX
RB1/INT1/AN8 RB0/INT0/FLT0/AN10 V
DD
VSS RD7/PSP7/P1D RD6/PSP6/P1C
RD5/PSP5/P1B RD4/PSP4/ECCP1/P1A RC7/RX/DT RC6/TX/CK RC5/SDO RC4/SDI/SDA RD3/PSP3/C2IN­RD2/PSP2/C2IN+
DS39625C-page 2 Preliminary © 2007 Microchip Technology Inc.

Pin Diagrams (Continued)

44-Pin TQFP
RD4/PSP4/ECCP1/P1A
RB0/INT0/FLT0/AN10
RC7/RX/DT
RD5/PSP5/P1B RD6/PSP6/P1C
RD7/PSP7/P1D
RB1/INT1/AN8
RB2/INT2/CANTX
RB3/CANRX
V
SS
VDD
PIC18F2585/2680/4585/4680
RC6/TX/CK
RC5/SDO
RC4/SDI/SDA
RD3/PSP3/C2IN-
RD2/PSP2/C2IN+
RD1/PSP1/C1IN-
RD0/PSP0/C1IN+
RC3/SCK/SCL
RC2/CCP1
RC1/T1OSI
NC
363435
1819202122
16
17
37
38
33 32 31 30 29 28 27 26 25 24 23
NC RC0/T1OSO/T13CKI OSC2/CLKO/RA6 OSC1/CLKI/RA7
SS
V VDD RE2/CS/AN7/C2OUT RE1/WR
/AN6/C1OUT
RE0/RD
/AN5 RA5/AN4/SS RA4/T0CKI
/HLVDIN
1 2 3
4 5 6 7 8 9 10 11
44
121314
414039
42
43
PIC18F4585 PIC18F4680
15
44-Pin QFN
RD4/PSP4/ECCP1/P1A
RB0/INT0/FLT0/AN10
RC7/RX/DT
RD5/PSP5/P1B RD6/PSP6/P1C
RD7/PSP7/P1D
RB1/INT1/AN8
RB2/INT2/CANTX
V
AVDD
VDD
NC
NC
RB4/KBI0/AN9
RB5/KBI1/PGM
RC6/TX/CK
RC5/SDO
RC4/SDI/SDA
RD3/PSP3/C2IN-
4443424140
1 2 3
4
5
SS
6 7 8 9 10 11
121314
PIC18F4585 PIC18F4680
15
RB7/KBI3/PGD
RB6/KBI2/PGC
RD2/PSP2/C2IN+
RD1/PSP1/C1IN-
RD0/PSP0/C1IN+
38
39
1819202122
16
17
MCLR/VPP/RE3
REF
RA0/AN0/CV
RC3/SCK/SCL
37
REF-
RA1/AN1
RA2/AN2/V
RC2/CCP1
RC1/T1OSI
363435
33 32 31 30 29 28 27 26 25 24 23
RA3/AN3/VREF+
RC0/T1OSO/T13CKI
OSC2/CLKO/RA6 OSC1/CLKI/RA7
SS
V AVSS
VDD AVDD RE2/CS/AN7/C2OUT RE1/WR
/AN6/C1OUT
RE0/RD
/AN5 RA5/AN4/SS RA4/T0CKI
/HLVDIN
NC
RB3/CANRX
RB4/KBI0/AN9
RB5/KBI1/PGM
RB6/KBI2/PGC
RB7/KBI3/PGD
REF
REF-
RA1/AN1
RA2/AN2/V
MCLR/VPP/RE3
RA0/AN0/CV
RA3/AN3/VREF+
© 2007 Microchip Technology Inc. Preliminary DS39625C-page 3
PIC18F2585/2680/4585/4680

Table of Contents

1.0 Device Overview.......................................................................................................................................................................... 7
2.0 Oscillator Configurations............................................................................................................................................................23
3.0 Power Managed Modes .............................................................................................................................................................33
4.0 Reset.......................................................................................................................................................................................... 41
5.0 Memory Organization................................................................................................................................................................. 61
6.0 Flash Program Memory.............................................................................................................................................................. 95
7.0 Data EEPROM Memory........................................................................................................................................................... 105
8.0 8 x 8 Hardware Multiplier..........................................................................................................................................................111
9.0 Interrupts.................................................................................................................................................................................. 113
10.0 I/O Ports................................................................................................................................................................................... 129
11.0 Timer0 Module ......................................................................................................................................................................... 147
12.0 Timer1 Module ......................................................................................................................................................................... 151
13.0 Timer2 Module ......................................................................................................................................................................... 157
14.0 Timer3 Module ......................................................................................................................................................................... 159
15.0 Capture/Compare/PWM (CCP1) Modules ...............................................................................................................................163
16.0 Enhanced Capture/Compare/PWM (ECCP1) Module.............................................................................................................. 173
17.0 Master Synchronous Serial Port (MSSP) Module ....................................................................................................................187
18.0 Enhanced Universal Synchronous Receiver Transmitter (EUSART)....................................................................................... 227
19.0 10-Bit Analog-to-Digital Converter (A/D) Module .....................................................................................................................247
20.0 Comparator Module..................................................................................................................................................................257
21.0 Comparator Voltage Reference Module...................................................................................................................................263
22.0 High/Low-Voltage Detect (HLVD)............................................................................................................................................. 267
23.0 ECAN™ Technology ................................................................................................................................................................ 273
24.0 Special Features of the CPU.................................................................................................................................................... 343
25.0 Instruction Set Summary..........................................................................................................................................................361
26.0 Development Support............................................................................................................................................................... 411
27.0 Electrical Characteristics..........................................................................................................................................................415
28.0 DC and AC Characteristics Graphs and Tables.......................................................................................................................451
29.0 Packaging Information.............................................................................................................................................................. 453
Appendix A: Revision History............................................................................................................................................................. 461
Appendix B: Device Differences......................................................................................................................................................... 461
Appendix C: Conversion Considerations ........................................................................................................................................... 462
Appendix D: Migration From Baseline to Enhanced Devices............................................................................................................. 462
Appendix E: Migration from Mid-Range to Enhanced Devices .......................................................................................................... 463
Appendix F: Migration from High-End to Enhanced Devices............................................................................................................. 463
Index ..................................................................................................................................................................................................465
The Microchip Web Site..................................................................................................................................................................... 477
Customer Change Notification Service ..............................................................................................................................................477
Customer Support..............................................................................................................................................................................477
Reader Response.............................................................................................................................................................................. 478
PIC18F2585/2680/4585/4680 Product Identification System ............................................................................................................ 479
DS39625C-page 4 Preliminary © 2007 Microchip Technology Inc.
PIC18F2585/2680/4585/4680
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 products. To this end, we will continue to improve our publications to better suit your needs. Our publications will be refined and enhanced as new volumes and updates are introduced.
If you have any questions or comments regarding this publication, please contact the Marketing Communications Department via E-mail at docerrors@microchip.com or fax the Reader Response Form in the back of this data sheet to (480) 792-4150. We welcome your feedback.

Most Current Data Sheet

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http://www.microchip.com
You can determine the version of a data sheet by examining its literature number found on the bottom outside corner of any page. The last character of the literature number is the version number, (e.g., DS30000A is version A of document DS30000).

Errata

An errata sheet, describing minor operational differences from the data sheet and recommended workarounds, may exist for current devices. As device/documentation issues become known to us, we will publish an errata sheet. The errata will specify the revision of silicon and revision of document to which it applies.
To determine if an errata sheet exists for a particular device, please check with one of the following:
• Microchip’s Worldwide Web site; http://www.microchip.com
• Your local Microchip sales office (see last page) When contacting a sales office, please specify which device, revision of silicon and data sheet (include literature number) you are
using.

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Register on our web site at www.microchip.com to receive the most current information on all of our products.
© 2007 Microchip Technology Inc. Preliminary DS39625C-page 5
PIC18F2585/2680/4585/4680
NOTES:
DS39625C-page 6 Preliminary © 2007 Microchip Technology Inc.
PIC18F2585/2680/4585/4680

1.0 DEVICE OVERVIEW

This document contains device specific information for the following devices:
• PIC18F2585
• PIC18F2680
• PIC18F4585
• PIC18F4680 This family of devices 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. In addition to these features, the PIC18F2585/2680/4585/4680 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 PIC18F2585/2680/4585/4680 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 can also run 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.
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 1.1 and 2.1 μA, respectively.
Extended Instruction Set: In addition to the standard 75 instructions of the PIC18 instruction set, PIC18F2585/2680/4585/4680 devices also provide an optional extension to the core CPU functionality. The added features include eight additional instructions that augment indirect and indexed addressing operations and the implementation of Indexed Literal Offset Addressing mode for many of the standard PIC18 instructions.

1.1.2 MULTIPLE OSCILLATOR OPTIONS AND FEATURES

All of the devices in the PIC18F2585/2680/4585/4680 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 which provides an
8 MHz clock (±2% accuracy) and an INTRC source (approximately 31 kHz, stable over temperature and V 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.
• A Phase Lock Loop (PLL) frequency multiplier,
available to both the high-speed crystal and internal 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.
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 refer­ence 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.
DD), as well as a range of
© 2007 Microchip Technology Inc. Preliminary DS39625C-page 7
PIC18F2585/2680/4585/4680

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 inter­nal 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.
Extended Instruction Set: The PIC18F2585/2680/4585/4680 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 CCP1 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 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 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).
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 prescaler, allowing a time-out range from 4 ms to over 131 seconds, that is stable across operating voltage and temperature.

1.3 Details on Individual Family Members

Devices in the PIC18F2585/2680/4585/4680 family are available in 28-pin (PIC18F2X8X) and 40/44-pin (PIC18F4X8X) 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 six ways:
1. Flash program memory (48 Kbytes for
PIC18FX585 devices, 64 Kbytes for PIC18FX680).
2. A/D channels (8 for PIC18F2X8X devices, 11 for
PIC18F4X8X devices).
3. I/O ports (3 bidirectional ports and 1 input only
port on PIC18F2X8X devices, 5 bidirectional ports on PIC18F4X8X devices).
4. CCP1 and Enhanced CCP1 implementation
(PIC18F2X8X devices have 1 standard CCP1 module, PIC18F4X8X devices have one standard CCP1 module and one ECCP1 module).
5. Parallel Slave Port (present only on
PIC18F4X8X devices).
6. PIC18F4X8X devices provide two comparators.
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.
Like all Microchip PIC18 devices, members of the PIC18F2585/2680/4585/4680 family are available as both standard and low-voltage devices. Standard devices with Enhanced Flash memory, designated with an “F” in the part number (such as PIC18F2585), accommodate an operating V Low-voltage parts, designated by “LF” (such as PIC18LF2585), function over an extended V of 2.0V to 5.5V.
DD range of 4.2V to 5.5V.
DD range
DS39625C-page 8 Preliminary © 2007 Microchip Technology Inc.
PIC18F2585/2680/4585/4680

TABLE 1-1: DEVICE FEATURES

Features PIC18F2585 PIC18F2680 PIC18F4585 PIC18F4680
Operating Frequency DC – 40 MHz DC – 40 MHz DC – 40 MHz DC – 40 MHz Program Memory (Bytes) 49152 65536 49152 65536 Program Memory (Instructions) 24576 32768 24576 32768 Data Memory (Bytes) 3328 3328 3328 3328 Data EEPROM Memory (Bytes) 1024 1024 1024 1024 Interrupt Sources 19 19 20 20 I/O Ports Ports A, B, C, (E) Ports A, B, C, (E) Ports A, B, C, D, E Ports A, B, C, D, E Timers 4 4 4 4 Capture/Compare/PWM Modules 1 1 1 1 Enhanced Capture/
Compare/PWM Modules ECAN Module 1 1 1 1 Serial Communications MSSP,
Enhanced USART Parallel Communications (PSP) No No Yes Yes 10-bit Analog-to-Digital Module 8 Input Channels 8 Input Channels 11 Input Channels 11 Input Channels Comparators 0 0 2 2 Resets (and Delays) POR, BOR,
RESET Instruction,
MCLR
Programmable High/Low-Voltage Detect
Programmable Brown-out Reset Yes Yes Yes Yes Instruction Set 75 Instructions;
83 with Extended
Packages 28-pin PDIP
0011
MSSP,
Enhanced USART
POR, BOR,
RESET Instruction,
Stack Full,
Stack Underflow
(PWRT, OST),
(optional),
WDT
Yes Ye s Yes Yes
Instruction Set
enabled
28-pin SOIC
Stack Full,
Stack Underflow
(PWRT, OST),
(optional),
MCLR
WDT
75 Instructions;
83 with Extended
Instruction Set
enabled
28-pin PDIP 28-pin SOIC
MSSP,
Enhanced USART
POR, BOR,
RESET Instruction,
Stack Full,
Stack Underflow
(PWRT, OST),
(optional),
MCLR
WDT
75 Instructions;
83 with Extended
Instruction Set
enabled
40-pin PDIP
44-pin QFN
44-pin TQFP
MSSP,
Enhanced USART
POR, BOR,
RESET Instruction,
Stack Full,
Stack Underflow
(PWRT, OST),
(optional),
MCLR
WDT
75 Instructions;
83 with Extended
Instruction Set
enabled
40-pin PDIP
44-pin QFN
44-pin TQFP
© 2007 Microchip Technology Inc. Preliminary DS39625C-page 9
PIC18F2585/2680/4585/4680

FIGURE 1-1: PIC18F2585/2680 (28-PIN) BLOCK DIAGRAM

Table Pointer<21>
inc/dec logic
21
Address Latch
Program Memory
(48/64 Kbytes)
Data Latch
Instruction Bus <16>
(2)
OSC1
(2)
OSC2
T1OSI
T1OSO
(1)
MCLR VDD,
SS
V
20
8
Table Latch
ROM Latch
Instruction
Decode &
Control
Internal
Oscillator
Block
INTRC
Oscillator
8 MHz
Oscillator
Single-Supply Programming
In-Circuit
Debugger
8
PCLATH
PCLATU
PCH PCL
PCU
Program Counter
31 Level Stack
STKPTR
IR
State Machine Control Signals
Power-up
Oscillator
Start-up Timer
Power-on
Watchdog
Brown-out
Fail-Safe
Clock Monitor
Data Bus<8>
8
Timer
Reset Timer
Reset
Data Latch
Data Memory
(3.9 Kbytes)
Address Latch
12
Data Address<12>
44
12
FSR0 FSR1 FSR2
logic
8 x 8 Multiply
W
8
ALU<8>
Access
Bank
PRODLPRODH
8
8
12
8
8
8
8
BSR
3
BITOP
8
Band Gap Reference
inc/dec
Address
Decode
PORTA
PORTB
PORTC
PORTE
RA0/AN0 RA1/AN1 RA2/AN2/VREF­RA3/AN3/VREF+ RA4/T0CKI RA5/AN4/SS OSC2/CLKO/RA6 OSC1/CLKI/RA7
RB0/INT0/AN10 RB1/INT1/AN8 RB2/INT2/CANTX RB3/CANRX RB4/KBI0/AN9 RB5/KBI1/PGM RB6/KBI2/PGC RB7/KBI3/PGD
RC0/T1OSO/T13CKI RC1/T1OSI RC2/CCP1 RC3/SCK/SCL RC4/SDI/SDA RC5/SDO RC6/TX/CK RC7/RX/DT
MCLR/VPP/RE3
/HLVDIN
(1)
BOR
HLVD
Note 1: RE3 is multiplexed with MCLR and is only available when the MCLR Resets are disabled.
2: OSC1/CLKI and OSC2/CLKO are only available in select oscillator modes and when these pins are not being used as digital I/O.
Data
EEPROM
CCP1
Refer to Section 2.0 “Oscillator Configurations” for additional information.
ECCP1
MSSP
Timer2Timer1 Timer3Timer0
EUSARTComparator
ADC
10-bit
ECAN
DS39625C-page 10 Preliminary © 2007 Microchip Technology Inc.
PIC18F2585/2680/4585/4680

FIGURE 1-2: PIC18F4585/4680 (40/44-PIN) BLOCK DIAGRAM

Table Pointer<21>
inc/dec logic
21
Address Latch
Program Memory
(48/64 Kbytes)
Data Latch
20
8
PCLATH
PCLATU
PCH PCL
PCU
Program Counter
31 Level Stack
Table Latch
ROM Latch
IR
Instruction
Decode &
Control
Data Bus<8>
8
8
Data Latch
Data Memory
(3.9 Kbytes)
Address Latch
12
Data Address<12>
44
BSR
BITOP
3
8
Access
12
PRODLPRODH
8 x 8 Multiply
8
PORTD
8
RD0/PSP0
/C1IN+
8
ALU<8>
8
PORTE
BOR
HLVD
Note 1: RE3 is multiplexed with MCLR
2: OSC1/CLKI and OSC2/CLKO are only available in select oscillator modes and when these pins are not being used as digital I/O.
Data
EEPROM
CCP1
Refer to Section 2.0 “Oscillator Configurations” for additional information.
ECCP1
MSSP
and is only available when the MCLR Resets are disabled.
Timer2Timer1 Timer3Timer0
EUSARTComparator
ADC
10-bit
RE0/RD/AN5 RE1/WR/AN6/C1OUT RE2/CS/AN7/C2OUT MCLR/VPP/RE3
(1)
© 2007 Microchip Technology Inc. Preliminary DS39625C-page 11
PIC18F2585/2680/4585/4680
TABLE 1-2: PIC18F2585/2680 PINOUT I/O DESCRIPTIONS
Pin
Pin Name
MCLR
/VPP/RE3
MCLR VPP
RE3
OSC1/CLKI/RA7
OSC1 CLKI RA7
OSC2/CLKO/RA6
OSC2 CLKO RA6
Legend: TTL = TTL compatible input CMOS = CMOS compatible input or output
ST = Schmitt Trigger input with CMOS levels I = Input O = Output P = Power
Number
PDIP, SOIC
10
Pin
Buffer
Type
1
9
P
I/O
O O
I/O
Type
Master Clear (input) or programming voltage (input).
I
ST
I
ST
I
ST
I
CMOS
TTL
— —
TTL
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. External clock source input. Always associated with pin function OSC1. (See related OSC1/CLKI, OSC2/CLKO pins.) General purpose I/O pin.
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.
Description
DS39625C-page 12 Preliminary © 2007 Microchip Technology Inc.
PIC18F2585/2680/4585/4680
TABLE 1-2: PIC18F2585/2680 PINOUT I/O DESCRIPTIONS (CONTINUED)
Pin
Pin Name
RA0/AN0
RA0 AN0
RA1/AN1
RA1 AN1
RA2/AN2/V
RA3/AN3/V
RA4/T0CKI
RA5/AN4/SS
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
REF-
RA2 AN2
REF-
V
REF+
RA3 AN3
REF+
V
RA4 T0CKI
/HLVDIN RA5 AN4 SS HLVDIN
ST = Schmitt Trigger input with CMOS levels I = Input O = Output P = Power
Number
PDIP, SOIC
2
3
4
5
6
7
Pin
Buffer
Typ e
Type
I/OITTL
Analog
I/OITTL
Analog
I/O
I/O
I/OITTL
I/O
TTL
I
Analog
I
Analog
TTL
I
Analog
I
Analog
TTL
I
Analog
I
TTL
I
Analog
PORTA is a bidirectional I/O port.
Digital I/O. Analog input 0.
Digital I/O. Analog input 1.
Digital I/O. Analog input 2. A/D reference voltage (low) input.
Digital I/O. Analog input 3. A/D reference voltage (high) input.
Digital I/O.
ST
Timer0 external clock input.
Digital I/O. Analog input 4. SPI slave select input. High/Low-Voltage Detect input.
Description
© 2007 Microchip Technology Inc. Preliminary DS39625C-page 13
PIC18F2585/2680/4585/4680
TABLE 1-2: PIC18F2585/2680 PINOUT I/O DESCRIPTIONS (CONTINUED)
Pin
Pin Name
RB0/INT0/AN10
RB0 INT0 AN10
RB1/INT1/AN8
RB1 INT1 AN8
RB2/INT2/CANTX
RB2 INT2 CANTX
RB3/CANRX
RB3 CANRX
RB4/KBI0/AN9
RB4 KBI0 AN9
RB5/KBI1/PGM
RB5 KBI1 PGM
RB6/KBI2/PGC
RB6 KBI2 PGC
RB7/KBI3/PGD
RB7 KBI3 PGD
Legend: TTL = TTL compatible input CMOS = CMOS compatible input or output
ST = Schmitt Trigger input with CMOS levels I = Input O = Output P = Power
Number
PDIP, SOIC
21
22
23
24
25
26
27
28
Pin
Buffer
Type
Type
I/O
I/O
I/O
I/OITTL
I/O
I/O I/O
I/O I/O
I/O I/O
TTL I I
Analog
TTL I I
Analog
TTL I
O
TTL
TTL
TTL I
TTL I
Analog
TTL I
TTL
TTL I
TTL
TTL I
TTL
Description
PORTB is a bidirectional I/O port. PORTB can be software programmed for internal weak pull-ups on all inputs.
Digital I/O.
ST
ST
ST
ST
ST
ST
External interrupt 0. Analog input 10.
Digital I/O. External interrupt 1. Analog input 8.
Digital I/O. External interrupt 2. CAN bus TX.
Digital I/O. CAN bus RX.
Digital I/O. Interrupt-on-change pin. Analog input 9.
Digital I/O. Interrupt-on-change pin. Low-Voltage ICSP™ Programming enable pin.
Digital I/O. Interrupt-on-change pin. In-Circuit Debugger and ICSP programming clock pin.
Digital I/O. Interrupt-on-change pin. In-Circuit Debugger and ICSP programming data pin.
DS39625C-page 14 Preliminary © 2007 Microchip Technology Inc.
PIC18F2585/2680/4585/4680
TABLE 1-2: PIC18F2585/2680 PINOUT I/O DESCRIPTIONS (CONTINUED)
Pin
Pin Name
RC0/T1OSO/T13CKI
RC0 T1OSO T13CKI
RC1/T1OSI
RC1 T1OSI
RC2/CCP1
RC2 CCP1
RC3/SCK/SCL
RC3 SCK SCL
RC4/SDI/SDA
RC4 SDI SDA
RC5/SDO
RC5 SDO
RC6/TX/CK
RC6 TX CK
RC7/RX/DT
RC7 RX
DT RE3 See MCLR VSS 8, 19 P Ground reference for logic and I/O pins.
DD 20 P Positive supply for logic and I/O pins.
V Legend: TTL = TTL compatible input CMOS = CMOS compatible input or output
ST = Schmitt Trigger input with CMOS levels I = Input O = Output P = Power
Number
PDIP, SOIC
11
12
13
14
15
16
17
18
Pin
Buffer
Typ e
I/O
O
I
I/O
ISTCMOS
I/O I/O
I/O I/O I/O
I/O
I
I/O
I/O
O
I/O
O
I/O
I/O
I
I/O
Type
ST
ST
ST ST
ST ST ST
ST ST ST
ST
ST
ST
ST ST ST
Description
PORTC is a bidirectional I/O port.
Digital I/O. Timer1 oscillator output. Timer1/Timer3 external clock input.
Digital I/O. Timer1 oscillator input.
Digital I/O. Capture1 input/Compare1 output/PWM1 output.
Digital I/O. Synchronous serial clock input/output for SPI mode. Synchronous serial clock input/output for I
Digital I/O. SPI data in.
2
C data I/O.
I
Digital I/O. SPI data out.
Digital I/O. EUSART asynchronous transmit. EUSART synchronous clock (see related RX/DT).
Digital I/O. EUSART asynchronous receive. EUSART synchronous data (see related TX/CK).
/VPP/RE3 pin.
2
C™ mode.
© 2007 Microchip Technology Inc. Preliminary DS39625C-page 15
PIC18F2585/2680/4585/4680
TABLE 1-3: PIC18F4585/4680 PINOUT I/O DESCRIPTIONS
Pin Name
/VPP/RE3
MCLR
MCLR VPP
RE3
OSC1/CLKI/RA7
OSC1
CLKI
RA7
OSC2/CLKO/RA6
OSC2 CLKO
RA6
Legend: TTL = TTL compatible input CMOS = CMOS compatible input or output
ST = Schmitt Trigger input with CMOS levels I = Input O = Output P = Power
Pin Number
PDIP QFN TQFP
11818
13 32 30
14 33 31
Pin
Typ e
I
P
I
I
I
I/O
O O
I/O
Buffer
Type
ST
ST
ST
CMOS
TTL
— —
TTL
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; CMOS otherwise. External clock source input. Always associated with pin function OSC1. (See related OSC1/CLKI, OSC2/CLKO pins.) General purpose I/O pin.
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.
DS39625C-page 16 Preliminary © 2007 Microchip Technology Inc.
PIC18F2585/2680/4585/4680
TABLE 1-3: PIC18F4585/4680 PINOUT I/O DESCRIPTIONS (CONTINUED)
Pin Name
RA0/AN0/CVREF
RA0
AN0
CVREF RA1/AN1
RA1
AN1 RA2/AN2/V
RA3/AN3/V
RA4/T0CKI
RA5/AN4/SS
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
REF-
RA2
AN2
REF-
V
REF+
RA3
AN3
REF+
V
RA4
T0CKI
/HLVDIN RA5 AN4 SS HLVDIN
ST = Schmitt Trigger input with CMOS levels I = Input O = Output P = Power
Pin Number
PDIP QFN TQFP
21919
32020
42121
52222
62323
72424
Pin
Buffer
Typ e
Type
I/O
I
Analog
O
Analog
I/OITTL
Analog
I/O
I
Analog
I
Analog
I/O
I
Analog
I
Analog
I/OITTL
I/O
I
Analog I I
Analog
PORTA is a bidirectional I/O port.
TTL
TTL
TTL
ST
TTL TTL
Digital I/O. Analog input 0. Analog comparator reference output.
Digital I/O. Analog input 1.
Digital I/O. Analog input 2. A/D reference voltage (low) input.
Digital I/O. Analog input 3. A/D reference voltage (high) input.
Digital I/O. Timer0 external clock input.
Digital I/O. Analog input 4. SPI slave select input. High/Low-Voltage Detect input.
Description
© 2007 Microchip Technology Inc. Preliminary DS39625C-page 17
PIC18F2585/2680/4585/4680
TABLE 1-3: PIC18F4585/4680 PINOUT I/O DESCRIPTIONS (CONTINUED)
Pin Name
RB0/INT0/FLT0/AN10
RB0 INT0 FLT0 AN10
RB1/INT1/AN8
RB1 INT1 AN8
RB2/INT2/CANTX
RB2 INT2 CANTX
RB3/CANRX
RB3 CANRX
RB4/KBI0/AN9
RB4 KBI0 AN9
RB5/KBI1/PGM
RB5 KBI1 PGM
RB6/KBI2/PGC
RB6 KBI2 PGC
RB7/KBI3/PGD
RB7 KBI3 PGD
Legend: TTL = TTL compatible input CMOS = CMOS compatible input or output
ST = Schmitt Trigger input with CMOS levels I = Input O = Output P = Power
Pin Number
PDIP QFN TQFP
33 9 8
34 10 9
35 11 10
36 12 11
37 14 14
38 15 15
39 16 16
40 17 17
Pin
Buffer
Typ e
Type
I/O
I I I
Analog
I/O
I I
Analog
I/O
I
O
I/OITTL
I/O
I I
Analog
I/O
I
I/O
I/O
I
I/O
I/O
I
I/O
Description
PORTB is a bidirectional I/O port. PORTB can be software programmed for internal weak pull-ups on all inputs.
TTL
ST ST
TTL
ST
TTL
ST
TTL
TTL
TTL TTL
TTL TTL
ST
TTL TTL
ST
TTL TTL
ST
Digital I/O. External interrupt 0. Enhanced PWM Fault input (ECCP1 module). Analog input 10.
Digital I/O. External interrupt 1. Analog input 8.
Digital I/O. External interrupt 2. CAN bus TX.
Digital I/O. CAN bus RX.
Digital I/O. Interrupt-on-change pin. Analog input 9.
Digital I/O. Interrupt-on-change pin. Low-Voltage ICSP™ Programming enable pin.
Digital I/O. Interrupt-on-change pin. In-Circuit Debugger and ICSP programming clock pin.
Digital I/O. Interrupt-on-change pin. In-Circuit Debugger and ICSP programming data pin.
DS39625C-page 18 Preliminary © 2007 Microchip Technology Inc.
PIC18F2585/2680/4585/4680
TABLE 1-3: PIC18F4585/4680 PINOUT I/O DESCRIPTIONS (CONTINUED)
Pin Name
RC0/T1OSO/T13CKI
RC0 T1OSO T13CKI
RC1/T1OSI
RC1 T1OSI
RC2/CCP1
RC2 CCP1
RC3/SCK/SCL
RC3 SCK
SCL
RC4/SDI/SDA
RC4 SDI SDA
RC5/SDO
RC5 SDO
RC6/TX/CK
RC6 TX CK
RC7/RX/DT
RC7 RX DT
Legend: TTL = TTL compatible input CMOS = CMOS compatible input or output
ST = Schmitt Trigger input with CMOS levels I = Input O = Output P = Power
Pin Number
PDIP QFN TQFP
15 34 32
16 35 35
17 36 36
18 37 37
23 42 42
24 43 43
25 44 44
26 1 1
Pin
Buffer
Typ e
I/O
O
I
I/OIST
CMOS
I/O I/OSTST
I/O I/O
I/O
I/O
I
I/O
I/OOST
I/O
O
I/O
I/O
I
I/O
Type
ST
ST
ST ST
ST
ST ST ST
ST
ST
ST ST ST
Description
PORTC is a bidirectional I/O port.
Digital I/O. Timer1 oscillator output. Timer1/Timer3 external clock input.
Digital I/O. Timer1 oscillator input.
Digital I/O. Capture1 input/Compare1 output/PWM1 output.
Digital I/O. Synchronous serial clock input/output for SPI mode. Synchronous serial clock input/output for
2
C™ mode.
I
Digital I/O. SPI data in.
2
C data I/O.
I
Digital I/O. SPI data out.
Digital I/O. EUSART asynchronous transmit. EUSART synchronous clock (see related RX/DT).
Digital I/O. EUSART asynchronous receive. EUSART synchronous data (see related TX/CK).
© 2007 Microchip Technology Inc. Preliminary DS39625C-page 19
PIC18F2585/2680/4585/4680
TABLE 1-3: PIC18F4585/4680 PINOUT I/O DESCRIPTIONS (CONTINUED)
Pin Name
RD0/PSP0/C1IN+
RD0 PSP0 C1IN+
RD1/PSP1/C1IN-
RD1 PSP1 C1IN-
RD2/PSP2/C2IN+
RD2 PSP2 C2IN+
RD3/PSP3/C2IN-
RD3 PSP3 C2IN-
RD4/PSP4/ECCP1/ P1A
RD4 PSP4 ECCP1 P1A
RD5/PSP5/P1B
RD5 PSP5 P1B
RD6/PSP6/P1C
RD6 PSP6 P1C
RD7/PSP7/P1D
RD7 PSP7 P1D
Legend: TTL = TTL compatible input CMOS = CMOS compatible input or output
ST = Schmitt Trigger input with CMOS levels I = Input O = Output P = Power
Pin Number
PDIP QFN TQFP
19 38 38
20 39 39
21 40 40
22 41 41
27 2 2
28 3 3
29 4 4
30 5 5
Pin
Typ e
I/O I/O
I
I/O I/O
I
I/O I/O
I
I/O I/O
I
I/O I/O I/O
O
I/O I/O
O
I/O I/O
O
I/O I/O
O
Buffer
Type
ST
TTL
Analog
ST
TTL
Analog
ST
TTL
Analog
ST
TTL
Analog
ST
TTL
ST
TTL
ST TTL TTL
ST TTL TTL
ST TTL TTL
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 PSP module is enabled.
Digital I/O. Parallel Slave Port data. Comparator 1 input (+).
Digital I/O. Parallel Slave Port data. Comparator 1 input (-)
Digital I/O. Parallel Slave Port data. Comparator 2 input (+).
Digital I/O. Parallel Slave Port data. Comparator 2 input (-).
Digital I/O. Parallel Slave Port data. Capture2 input/Compare2 output/PWM2 output. ECCP1 PWM output A.
Digital I/O. Parallel Slave Port data. ECCP1 PWM output B.
Digital I/O. Parallel Slave Port data. ECCP1 PWM output C.
Digital I/O. Parallel Slave Port data. ECCP1 PWM output D.
DS39625C-page 20 Preliminary © 2007 Microchip Technology Inc.
PIC18F2585/2680/4585/4680
TABLE 1-3: PIC18F4585/4680 PINOUT I/O DESCRIPTIONS (CONTINUED)
Pin Name
RE0/RD
RE1/WR
RE2/CS
RE3 See MCLR V
V
NC 13 12, 13,
Legend: TTL = TTL compatible input CMOS = CMOS compatible input or output
/AN5 RE0 RD
AN5
/AN6/C1OUT RE1 WR
AN6 C1OUT
/AN7/C2OUT RE2 CS
AN7 C2OUT
SS 12,
DD 11, 32 7, 8,
ST = Schmitt Trigger input with CMOS levels I = Input O = Output P = Power
Pin Number
PDIP QFN TQFP
82525
92626
10 27 27
6, 30, 316, 29 P Ground reference for logic and I/O pins.
31
7, 28 P Positive supply for logic and I/O pins.
28, 29
33, 34
Pin
Buffer
Typ e
Type
PORTE is a bidirectional I/O port.
I/O
I/O
I/O
ST
I
TTL
I
Analog
ST
TTL
I
Analog
I
TTL
O
ST
I
TTL
I
Analog
O
TTL
No connect.
Digital I/O. Read control for Parallel Slave Port (see also WR and CS Analog input 5.
Digital I/O. Write control for Parallel Slave Port (see CS and RD Analog input 6. Comparator 1 output.
Digital I/O. Chip select control for Parallel Slave Port (see related RD Analog input 7. Comparator 2 output.
Description
pins).
pins).
and WR).
/VPP/RE3 pin.
© 2007 Microchip Technology Inc. Preliminary DS39625C-page 21
PIC18F2585/2680/4585/4680
NOTES:
DS39625C-page 22 Preliminary © 2007 Microchip Technology Inc.
PIC18F2585/2680/4585/4680

2.0 OSCILLATOR CONFIGURATIONS

2.1 Oscillator Types

PIC18F2585/2680/4585/4680 devices can be operated in ten different oscillator modes. The user can program the Configuration bits, FOSC3:FOSC0, in Configuration Register 1H to select one of these ten modes:
1. LP Low-Power Crystal
2. XT Crystal/Resonator
3. HS High-Speed Crystal/Resonator
4. HSPLL High-Speed Crystal/Resonator
with PLL enabled
5. RC External Resistor/Capacitor with
F
OSC/4 output on RA6
6. RCIO External Resistor/Capacitor with I/O
on RA6
7. INTIO1 Internal Oscillator with F
on RA6 and I/O on RA7
8. INTIO2 Internal Oscillator with I/O on RA6
and RA7
9. EC External Clock with F
10. ECIO External Clock with I/O on RA6

2.2 Crystal Oscillator/Ceramic Resonators

In XT, LP, HS or HSPLL Oscillator modes, a crystal or ceramic resonator is connected to the OSC1 and OSC2 pins to establish oscillation. Figure 2-1 shows the pin connections.
The oscillator design requires the use of a parallel cut crystal.
Note: Use of a series cut crystal may give a
frequency out of the crystal manufacturer’s specifications.
OSC/4 output
OSC/4 output
FIGURE 2-1: CRYSTAL/CERAMIC
RESONATOR OPERATION (XT, LP, HS OR HSPLL CONFIGURATION)
(1)
C1
(1)
C2
Note 1: See Table 2-1 and Table 2-2 for initial values of
2: A series resistor (R 3: R
OSC1
XTAL
OSC2
C1 and C2. strip cut crystals.
F varies with the oscillator mode chosen.
(3)
RF
Sleep
PIC18FXXXX
S) may be required for AT
To
Logic
TABLE 2-1: CAPACITOR SELECTION FOR
CERAMIC RESONATORS
Typical Capacitor Values Used:
Mode Freq OSC1 OSC2
XT 455 kHz
2.0 MHz
4.0 MHz
HS 8.0 MHz
16.0 MHz Capacitor values are for design guidance only. These capacitors were tested with the resonators
listed below for basic start-up and operation. These values are not optimized.
Different capacitor values may be required to produce acceptable oscillator operation. The user should test the performance of the oscillator over the expected
DD and temperature range for the application.
V See the notes on page 24 for additional information.
Resonators Used:
56 pF 47 pF 33 pF
27 pF 22 pF
56 pF 47 pF 33 pF
27 pF 22 pF
455 kHz 4.0 MHz
2.0 MHz 8.0 MHz
16.0 MHz
Note: When using resonators with frequencies
above 3.5 MHz, the use of HS mode, rather than XT mode, is recommended. HS mode may be used at any V
DD for
which the controller is rated. If HS is selected, it is possible that the gain of the oscillator will overdrive the resonator. Therefore, a series resistor should be placed between the OSC2 pin and the resonator. As a good starting point, the recommended value of R
© 2007 Microchip Technology Inc. Preliminary DS39625C-page 23
S is 330Ω.
PIC18F2585/2680/4585/4680
TABLE 2-2: CAPACITOR SELECTION FOR
CRYSTAL OSCILLATOR
Osc Type
LP 32 kHz 33 pF 33 pF
XT 1 MHz 33 pF 33 pF
HS 4 MHz 27 pF 27 pF
Capacitor values are for design guidance only. These capacitors were tested with the crystals listed
below for basic start-up and operation. These values
are not optimized.
Different capacitor values may be required to produce acceptable oscillator operation. The user should test the performance of the oscillator over the expected
DD and temperature range for the application.
V See the notes following this table for additional
information.
Note 1: Higher capacitance increases the stability
Crystal
Freq
200 kHz 15 pF 15 pF
4 MHz 27 pF 27 pF
8 MHz 22 pF 22 pF
20 MHz 15 pF 15 pF
Crystals Used:
32 kHz 4 MHz
200 kHz 8 MHz
1 MHz 20 MHz
of the oscillator but also increases the start-up time.
2: When operating below 3V V
using certain ceramic resonators at any voltage, it may be necessary to use the HS mode or switch to a crystal oscillator.
3: Since each resonator/crystal has its own
characteristics, the user should consult the resonator/crystal manufacturer for appropriate values of external components.
4: Rs may be required to avoid overdriving
crystals with low drive level specification.
5: Always verify oscillator performance over
DD and temperature range that is
the V expected for the application.
Typical Capacitor Values
Tested:
C1 C2
DD, or when
An external clock source may also be connected to the OSC1 pin in the HS mode, as shown in Figure 2-2.
FIGURE 2-2: EXTERNAL CLOCK
INPUT OPERATION (HS OSCILLATOR CONFIGURATION)
Clock from Ext. System
Open
OSC1
OSC2
PIC18FXXXX
(HS Mode)

2.3 External Clock Input

The EC and ECIO Oscillator modes require an external clock source to be connected to the OSC1 pin. There is no oscillator start-up time required after a Power-on Reset or after an exit from Sleep mode.
In the EC Oscillator mode, the oscillator frequency divided by 4 is available on the OSC2 pin. This signal may be used for test purposes or to synchronize other logic. Figure 2-3 shows the pin connections for the EC Oscillator mode.
FIGURE 2-3: EXTERNAL CLOCK
INPUT OPERATION (EC CONFIGURATION)
Clock from Ext. System
F
OSC/4
The ECIO Oscillator mode functions like the EC mode, except that the OSC2 pin becomes an additional general purpose I/O pin. The I/O pin becomes bit 6 of PORTA (RA6). Figure 2-4 shows the pin connections for the ECIO Oscillator mode.
FIGURE 2-4: EXTERNAL CLOCK
Clock from Ext. System
RA6
OSC1/CLKI
PIC18FXXXX
OSC2/CLKO
INPUT OPERATION (ECIO CONFIGURATION)
OSC1/CLKI
PIC18FXXXX
I/O (OSC2)
DS39625C-page 24 Preliminary © 2007 Microchip Technology Inc.
PIC18F2585/2680/4585/4680

2.4 RC Oscillator

For timing insensitive applications, the “RC” and “RCIO” device options offer additional cost savings. The actual oscillator frequency is a function of several factors:
• supply voltage
• values of the external resistor (R capacitor (C
EXT)
• operating temperature
Given the same device, operating voltage and tempera­ture and component values, there will also be unit-to-unit frequency variations. These are due to factors such as:
• normal manufacturing variation
• difference in lead frame capacitance between package types (especially for low C
• variations within the tolerance of limits of R
EXT
and C
In the RC Oscillator mode, the oscillator frequency divided by 4 is available on the OSC2 pin. This signal may be used for test purposes or to synchronize other logic. Figure 2-5 shows how the R/C combination is connected.

FIGURE 2-5: RC OSCILLATOR MODE

VDD
REXT
OSC1
CEXT
VSS
F
Recommended values: 3 kΩ ≤ REXT 100 kΩ
OSC/4
OSC2/CLKO
EXT > 20 pF
C
EXT) and
EXT values)
EXT
Internal
Clock
PIC18FXXXX

2.5 PLL Frequency Multiplier

A Phase Locked Loop (PLL) circuit is provided as an option for users who wish to use a lower frequency oscillator circuit or to clock the device up to its highest rated frequency from a crystal oscillator. This may be useful for customers who are concerned with EMI due to high-frequency crystals or users who require higher clock speeds from an internal oscillator.

2.5.1 HSPLL OSCILLATOR MODE

The HSPLL mode makes use of the HS mode oscillator for frequencies up to 10 MHz. A PLL then multiplies the oscillator output frequency by 4 to produce an internal clock frequency up to 40 MHz.
The PLL is only available to the crystal oscillator when the FOSC3:FOSC0 Configuration bits are programmed for HSPLL mode (= 0110).
FIGURE 2-7: PLL BLOCK DIAGRAM
(HS MODE)
HS Osc Enable
PLL Enable
(from Configuration Register 1H)
OSC2
OSC1
HS Mode
Crystal
Osc
IN
F FOUT
÷4
Phase
Comparator
Loop Filter
VCO
SYSCLK
MUX
The RCIO Oscillator mode (Figure 2-6) functions like the RC mode, except that the OSC2 pin becomes an additional general purpose I/O pin. The I/O pin becomes bit 6 of PORTA (RA6).

2.5.2 PLL AND INTOSC

The PLL is also available to the internal oscillator block in selected oscillator modes. In this configuration, the

FIGURE 2-6: RCIO OSCILLATOR MODE

VDD
PLL is enabled in software and generates a clock output of up to 32MHz. The operation of INTOSC with the PLL is described in Section 2.6.4 “PLL in INTOSC
REXT
OSC1
CEXT
VSS
RA6
Recommended values: 3 kΩ ≤ REXT 100 kΩ
© 2007 Microchip Technology Inc. Preliminary DS39625C-page 25
I/O (OSC2)
C
EXT > 20 pF
Internal
Clock
PIC18FXXXX
Modes”.
PIC18F2585/2680/4585/4680

2.6 Internal Oscillator Block

The PIC18F2585/2680/4585/4680 devices include an internal oscillator block which generates two different clock signals; either can be used as the microcontroller’s clock source. This may eliminate the need for external oscillator circuits on the OSC1 and/or OSC2 pins.
The main output (INTOSC) is an 8MHz clock source, which can be used to directly drive the device clock. It also drives a postscaler, which can provide a range of clock frequencies from 31 kHz to 4 MHz. The INTOSC output is enabled when a clock frequency from 125 kHz to 8 MHz is selected.
The other clock source is the internal RC oscillator (INTRC), which provides a nominal 31 kHz output. INTRC is enabled if it is selected as the device clock source; it is also enabled automatically when any of the following are enabled:
• Power-up Timer
• Fail-Safe Clock Monitor
• Watchdog Timer
• Two-Speed Start-up These features are discussed in greater detail in
Section 24.0 “Special Features of the CPU”. The clock source frequency (INTOSC direct, INTRC
direct or INTOSC postscaler) is selected by configuring the IRCF bits of the OSCCON register (Register 2-2).
2.6 enH918.5(t-unfg2sTD0.1710.7sh4o]TJ0 -2cc647.2.o(10.7sh4g)13.37ccl)12.4 81 Te.9(e)-1(2)-12u9
DS39625C-page 26 Preliminary © 2007 Microchip Technology Inc.
PIC18F2585/2680/4585/4680
REGISTER 2-1: OSCTUNE: OSCILLATOR TUNING REGISTER
R/W-0 R/W-0
INTSRC PLLEN
bit 7 bit 0
bit 7 INTSRC: Internal Oscillator Low-Frequency Source Select bit
1 = 31.25 kHz device clock derived from 8 MHz INTOSC source (divide-by-256 enabled) 0 = 31 kHz device clock derived directly from INTRC internal oscillator
bit 6 PLLEN: Frequency Multiplier PLL for INTOSC Enable bit
1 = PLL enabled for INTOSC (4 MHz and 8 MHz only) 0 = PLL disabled
Note 1: Available only in certain oscillator configurations; otherwise, this bit is unavailable
bit 5 Unimplemented: Read as ‘0’ bit 4-0 TUN4:TUN0: Frequency Tuning bits
01111 = Maximum frequency
00001 00000 = Center frequency. Oscillator module is running at the calibrated frequency. 11111
10000 = Minimum frequency
(1)
(1)
and reads as ‘0’. See text for details.
U-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0
TUN4 TUN3 TUN2 TUN1 TUN0
(1)
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 x = Bit is unknown
2.6.5.1 Compensating with the EUSART
An adjustment may be required when the EUSART begins to generate framing errors or receives data with errors while in Asynchronous mode. Framing errors indicate that the device clock frequency is too high. To adjust for this, decrement the value in OSCTUNE to reduce the clock frequency. On the other hand, errors in data may suggest that the clock speed is too low. To compensate, increment OSCTUNE to increase the clock frequency.
2.6.5.2 Compensating with the Timers
This technique compares device clock speed to some reference clock. Two timers may be used; one timer is clocked by the peripheral clock, while the other is clocked by a fixed reference source, such as the Timer1 oscillator.
Both timers are cleared, but the timer clocked by the reference generates interrupts. When an interrupt occurs, the internally clocked timer is read and both timers are cleared. If the internally clocked timer value is greater than expected, then the internal oscillator block is running too fast. To adjust for this, decrement the OSCTUNE register.
2.6.5.3 Compensating with the CCP1 Module in Capture Mode
The CCP1 module can use free running Timer1 (or Timer3), clocked by the internal oscillator block and an external event with a known period (i.e., AC power frequency). The time of the first event is captured in the CCPRxH:CCPRxL registers and is recorded for use later. When the second event causes a capture, the time of the first event is subtracted from the time of the second event. Since the period of the external event is known, the time difference between events can be calculated.
If the measured time is much greater than the calculated time, the internal oscillator block is running too fast. To compensate, decrement the OSCTUNE register. If the measured time is much less than the calculated time, the internal oscillator block is running too slow. To compensate, increment the OSCTUNE register.
© 2007 Microchip Technology Inc. Preliminary DS39625C-page 27
PIC18F2585/2680/4585/4680

2.7 Clock Sources and Oscillator Switching

Like previous PIC18 devices, the PIC2585/2680/ 4585/4680 family includes a feature that allows the device clock source to be switched from the main oscillator to an alternate low-frequency clock source. PIC18F2585/2680/4585/4680 devices offer two alter­nate clock sources. When an alternate clock source is enabled, the various power managed operating modes are available.
Essentially, there are three clock sources for these devices:
• Primary oscillators
• Secondary oscillators
• Internal oscillator block
The primary oscillators include the External Crystal and Resonator modes, the External RC modes, the External Clock modes and the internal oscillator block. The particular mode is defined by the FOSC3:FOSC0 Configuration bits. The details of these modes are covered earlier in this chapter.
The secondary oscillators are those external sources not connected to the OSC1 or OSC2 pins. These sources may continue to operate even after the controller is placed in a power managed mode.
PIC18F2585/2680/4585/4680 devices offer the Timer1 oscillator as a secondary oscillator. This oscillator, in all power managed modes, is often the time base for functions such as a real-time clock.
Most often, a 32.768kHz watch crystal is connected between the RC0/T1OSO/T13CKI and RC1/T1OSI pins. Like the LP mode oscillator circuit, loading capacitors are also connected from each pin to ground.
The Timer1 oscillator is discussed in greater detail in Section 12.3 “Timer1 Oscillator”.
In addition to being a primary clock source, the internal oscillator block is available as a power managed mode clock source. The INTRC source is also used as the clock source for several special features, such as the WDT and Fail-Safe Clock Monitor.
The clock sources for the PIC18F2585/2680/4585/4680 devices are shown in Figure 2-8. See Section 24.0 “Special Features of the CPU” for Configuration
register details.

FIGURE 2-8: PIC18F2585/2680/4585/4680 CLOCK DIAGRAM

PIC18FX585/X680
8 MHz 4 MHz
2 MHz 1 MHz
500 kHz
Postscaler
250 kHz 125 kHz
1 0
31 kHz
4 x PLL
OSCCON<6:4>
111
110
101
100
MUX
011
010
001
000
OSCTUNE<7>
HSPLL, INTOSC/PLL
OSC2
OSC1
T1OSO
T1OSI
Primary Oscillator
Sleep
Secondary Oscillator
T1OSCEN Enable Oscillator
OSCCON<6:4>
Internal
Oscillator
Block
8 MHz
Source INTRC
Source
31 kHz (INTRC)
OSCTUNE<6>
8 MHz
(INTOSC)
LP, XT, HS, RC, EC
T1OSC
Internal Oscillator
FOSC3:FOSC0
Peripherals
MUX
CPU
Clock
Control
Clock Source Option for other Modules
WDT, PWRT, FSCM and Two-Speed Startup
IDLEN
OSCCON<1:0>
DS39625C-page 28 Preliminary © 2007 Microchip Technology Inc.
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