PIC18F4685-I/ML - 96KB Flash 8-bit MCU w/ECAN, 44-QFN | Microchip
MPN: PIC18F4685-I/ML ✓ פעילPIC18F4685-I/ML סקירה
Key features include 1 KB of EEPROM data memory, nanoWatt Technology power management with multiple idle and sleep modes, an enhanced USART, MSSP (SPI/I2C) peripheral, two CCP/ECCP modules for PWM and capture/compare, and a 16-bit timer/counter. The integrated ECAN controller is compliant with CAN 2.0B active specification and supports both standard and extended identifiers with maskable filters, allowing reliable in-vehicle networking at bit rates up to 1 Mbit/s. The device is part of the PIC18F4685 family which includes the PIC18F2682/2685/4682/4685 variants in 28/40/44-pin packages.
The architecture uses an 8-bit data path with a 16-bit instruction word and a modified Harvard bus, providing linear memory addressing for both program and data. The enhanced Flash supports self-programming under software control, enabling in-field firmware updates and bootloader-style workflows. Hardware stack and interrupt controller support priority-based context handling, with up to 20 interrupt sources and two priority levels, making this device suitable for real-time control tasks.
Typical applications include automotive body and chassis ECUs (CAN nodes for body control, HVAC, instrument clusters), industrial CAN-based sensor networks, motor control loops where ECCP PWM drives half-bridges, sensor conditioning with on-chip 10-bit ADC, and consumer appliances requiring robust wired networking. The wide operating temperature range (-40C to +85C for the -I industrial grade) plus ECAN and nanoWatt features align it with both automotive passenger-compartment and industrial control deployments.
Designers should use MPLAB X IDE with the MPLAB XC8 compiler for firmware development and the PICkit 5 in-circuit debugger for programming and debugging. The QFN-44 package requires careful PCB layout with thermal vias under the exposed pad to manage the 5 V/40 MHz power dissipation envelope. The 96 KB Flash also enables large lookup-table and bootloader strategies that smaller PIC18 devices cannot host.
This page synthesizes distributor pricing, drop-in Microchip alternative MPNs, and practical design considerations not found in the manufacturer datasheet alone, including parametric proximity analysis versus PIC18F4682 and PIC18F4585 variants within the same 44-pin QFN footprint.
חלופות תחליף ישיר עבור PIC18F4685-I/ML — אותו מארז, תואם פין-לפין. חלקים במארז שונה הדורשים עיבוד מחדש של ה-PCB אינם נכללים.
וריאנטים בסדרה זו
דגמים מאותה סדרה התואמים Drop-in עם PIC18F4685-I/ML (אותו גורם צורה וטביעת רגל) — שונים ב Package, Timers, Operating Temperature, EEPROM, MSL Level.
PIC18F4682-I/ML
✅ Drop-Inצור קשר לקבלת מחיר
הצג גיליון נתונים ←PIC18F4585-I/ML
✅ Drop-Inצור קשר לקבלת מחיר
הצג גיליון נתונים ←PIC18F4680-I/P
✅ Drop-Inצור קשר לקבלת מחיר
הצג גיליון נתונים ←PIC18F4620-I/ML
✅ Drop-In📋 חלופה להתייחסות (לא בקטלוג)
PIC18F4480-I/ML
✅ Drop-Inצור קשר לקבלת מחיר
הצג גיליון נתונים ←PIC18F4685-I/ML דירוגים מרביים ומאפיינים חשמליים
| Family | PIC18F |
| Core | 8-bit PIC RISC |
| Program Memory Type | Enhanced Flash |
| Program Memory Size | 96 KB |
| Data RAM Size | 3328 bytes |
| Data EEPROM Size | 1024 bytes |
| Maximum CPU Frequency | 40 MHz |
| MIPS | 10 MIPS |
| Operating Voltage Range | 2.0 V to 5.5 V |
| טווח טמפרטורת פעולה | -40C to +85C (Industrial grade, I suffix) |
| ADC | 10-bit, up to 11 channels |
| CAN | ECAN (Enhanced CAN 2.0B active) on-chip |
| PWM Channels | ECCP/CCP |
| Timers | 16-bit and 8-bit Timer/Counter modules |
| UART | Enhanced USART (EUSART) |
| I2C/SPI | MSSP (SPI / I2C) peripheral |
| מארז | 44-pin QFN (ML) with exposed thermal pad |
| סוג הרכבה | Surface Mount |
| סטטוס RoHS | Compliant |
תצורת פינים של PIC18F4685-I/ML
| פין 1 | OSC1/CLKI — Oscillator input / external clock input |
| פין 2 | OSC2/CLKO — Oscillator output / clock output |
| פין 3 | MCLR — Master Clear (reset) input, active-low |
| פין 4 | RA0/AN0 — PORTA bit 0 / analog input 0 |
| פין 5 | RA1/AN1 — PORTA bit 1 / analog input 1 |
| פין 6 | RA2/AN2/VREF- — PORTA bit 2 / analog input 2 / ADC VREF- |
| פין 7 | RA3/AN3/VREF+ — PORTA bit 3 / analog input 3 / ADC VREF+ |
| פין 8 | RA4/T0CKI — PORTA bit 4 / Timer0 clock input |
| פין 9 | RA5/AN4/SS — PORTA bit 5 / analog input 4 / SPI slave select |
| פין 10 | VSS — Ground |
| פין 11 | VDD — Positive supply (2.0-5.5V) |
| פין 12 | RB0/INT0 — PORTB bit 0 / external interrupt 0 |
| פין 13 | RB1/INT1 — PORTB bit 1 / external interrupt 1 |
| פין 14 | RB2/INT2 — PORTB bit 2 / external interrupt 2 |
| פין 15 | RB3/CCP2 — PORTB bit 3 / CCP2 PWM/capture |
| פין 16 | RB4 — PORTB bit 4 |
| פין 17 | RB5/PGM — PORTB bit 5 / ICSP programming low-voltage |
| פין 18 | RB6/PGC — PORTB bit 6 / ICSP clock |
| פין 19 | RB7/PGD — PORTB bit 7 / ICSP data |
| פין 20 | VSS — Ground |
| פין 21 | VDD — Positive supply (2.0-5.5V) |
| פין 22 | RC0/T1OSO — PORTC bit 0 / Timer1 oscillator output |
| פין 23 | RC1/T1OSI — PORTC bit 1 / Timer1 oscillator input |
| פין 24 | RC2/CCP1 — PORTC bit 2 / ECCP1 PWM/capture |
| פין 25 | RC3/SCK/SCL — PORTC bit 3 / SPI clock / I2C clock |
| פין 26 | RC4/SDI/SDA — PORTC bit 4 / SPI data in / I2C data |
| פין 27 | RC5/SDO — PORTC bit 5 / SPI data out |
| פין 28 | RC6/TX/CK — PORTC bit 6 / EUSART TX / clock |
| פין 29 | RC7/RX/DT — PORTC bit 7 / EUSART RX / data |
| פין 30 | RD0 — PORTD bit 0 |
| פין 31 | RD1 — PORTD bit 1 |
| פין 32 | RD2 — PORTD bit 2 |
| פין 33 | RD3 — PORTD bit 3 |
| פין 34 | RD4/ECANRX — PORTD bit 4 / ECAN receive pin |
| פין 35 | RD5/ECANTX — PORTD bit 5 / ECAN transmit pin |
| פין 36 | RD6 — PORTD bit 6 |
| פין 37 | RD7 — PORTD bit 7 |
| פין 38 | VSS — Ground |
| פין 39 | VDD — Positive supply (2.0-5.5V) |
| פין 40 | RE0/RD — PORTE bit 0 / parallel port read |
| פין 41 | RE1/WR — PORTE bit 1 / parallel port write |
| פין 42 | RE2/CS — PORTE bit 2 / parallel port chip select |
| פין 43 | AVDD — Analog supply |
| פין 44 | AVSS — Analog ground |
יישומים טיפוסיים
PIC18F4685-I/ML מתאים עבור 6 יישוםs: Automotive CAN Body Control Module, Industrial CAN Sensor Network Node, BLDC Motor Control with ECAN Feedback, HVAC Climate Control Unit, Instrument Cluster CAN Display Driver, Building Automation / Smart Sensor Hub.
Automotive CAN Body Control Module
The PIC18F4685-I/ML is well suited for automotive body-control ECUs because its ECAN module is compliant with Bosch CAN 2.0B active and supports standard 11-bit plus extended 29-bit identifiers at bit rates up to 1 Mbit/s. With 96 KB Flash, designers can host the entire body-control application (HVAC control, lighting sequencer, door lock state machine) plus a bootloader for service updates over CAN. The 10-bit ADC handles analog sensor inputs (temperature, position) while ECCP PWM drives small actuators. The 44-pin QFN (ML) package offers a compact footprint under 10x10 mm and the -I temperature grade covers the -40C to +85C passenger-compartment environment.
מומלץ
Industrial CAN Sensor Network Node
For industrial sensor networks using CANopen or DeviceNet, the PIC18F4685-I/ML acts as a smart sensor node with on-chip ECAN handling bus arbitration and acceptance filtering so the CPU offloads message routing. The 10-bit ADC scans up to 11 analog inputs (temperature, pressure, flow) and the 16-bit timer accurately timestamps CAN messages. nanoWatt Technology enables sleep currents below 1 uA in battery-backed field nodes. Industrial EMC and surge immunity are improved by the wide 2.0-5.5 V supply tolerance, accepting 24 V bus-derived rails with a simple LDO dropper. The 3328-byte RAM accommodates CANopen object dictionary fragments and run-time diagnostics.
מומלץ
BLDC Motor Control with ECAN Feedback
The PIC18F4685-I/ML's ECCP (Enhanced Capture/Compare/PWM) module drives a 3-phase BLDC or PMSM motor with hardware fault shutdown and programmable dead-band control. The 10-bit ADC samples back-EMF or phase current through external shunt amplifiers while the 16-bit timer triggers commutation events deterministically. ECAN streams rotor speed, torque, and fault status back to a central controller, enabling distributed motor clusters in industrial robots and CNC machines. The 40 MHz / 10 MIPS core performs field-oriented control loops at switching frequencies up to 20 kHz. The -40C to +85C industrial range supports motor compartment installations.
מומלץ
HVAC Climate Control Unit
The PIC18F4685-I/ML drives HVAC climate-control panels where multiple temperature sensors (NTC thermistors, RTDs), humidity sensors, and user-interface keypads feed the 10-bit ADC. The 96 KB Flash holds full PID control algorithms for compressor, blower, and damper actuators while ECAN communicates with the vehicle's body controller or with the building's HVAC bus. PWM channels regulate blower speed and proportional valves, and the nanoWatt Technology idle modes drop current draw below 5 uA in standby. The 44-pin QFN (ML) keeps the PCB under 25x25 mm, leaving room for a compact in-dash or wall-mount enclosure.
מומלץ
Instrument Cluster CAN Display Driver
In automotive and industrial dashboards, the PIC18F4685-I/ML serves as a CAN-attached display controller that interprets vehicle CAN frames (RPM, speed, fuel, temperature) and drives a graphic LCD or segment display. With 96 KB Flash and 3328 bytes RAM, it can host full custom fonts, warning icons, and CANopen-style network management. The 10-bit ADC reads the cluster's photodiode for automatic dimming, and PWM channels drive LED backlight brightness. ECAN hardware filtering reduces CPU load by discarding non-relevant frames, freeing cycles for display refresh routines.
מומלץ
Building Automation / Smart Sensor Hub
In building automation, the PIC18F4685-I/ML aggregates multiple sensor inputs (PIR motion, CO2, light, temperature) and reports aggregated telemetry over a CAN bus using ECAN's maskable filters to handle bus traffic efficiently. The 10-bit ADC digitizes analog sensors, MSSP runs I2C sensors, and ECCP drives relay or TRIAC outputs for lighting control. The nanoWatt Technology sleep modes extend battery life in wireless gateway nodes. The wide 2.0-5.5 V supply range tolerates Power-over-Ethernet derived rails after a small LDO. With 96 KB Flash, the device can host BACnet or KNX-style application profiles.
מומלץ
סיכום מוצרים מומלצים
נתוני עזר הנדסיים עבור PIC18F4685-I/ML — השוואה, הנחיות תכנון ומידע על תאימות.
מדריך בחירה
השוואה עם חלופות
| פרמטר | מוצר זה | PIC18F4682-I/ML | PIC18F4585-I/ML | PIC18F4620-I/ML | PIC18F4480-I/ML |
|---|---|---|---|---|---|
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Package | 44-pin QFN (ML) | 44-pin QFN (ML) - same | 44-pin QFN (ML) - same | 44-pin QFN (ML) - same | 44-pin QFN (ML) - same |
| Flash Program Memory | 96 KB | 80 KB (-17%) | 48 KB (-50%) | 64 KB (-33%) | 16 KB (-83%) |
| Data RAM | 3328 bytes | 3328 bytes | 3328 bytes | 3986 bytes | 768 bytes (-77%) |
| CAN Module | ECAN (Enhanced) | ECAN (Enhanced) | Legacy CAN (no ECAN filters) | Legacy CAN | ECAN (Enhanced) |
| Maximum CPU Frequency | 40 MHz | 40 MHz | 40 MHz | 40 MHz | 40 MHz |
| ADC Resolution | 10-bit, 11 channels | 10-bit, 11 channels | 10-bit, 11 channels | 10-bit, 8 channels | 10-bit, 8 channels |
| Operating Temperature | -40C to +85C (I grade) | -40C to +85C (I grade) | -40C to +85C (I grade) | -40C to +85C (I grade) | -40C to +85C (I grade) |
מבדילים עיקריים
- Largest Flash in PIC18F4685/4682 family at 96 KB (לעומתPIC18F4682-I/ML)
- ECAN with hardware acceptance filtering vs legacy CAN (לעומתPIC18F4585-I/ML)
- Industrial temperature range -40C to +85C with ECAN (לעומתPIC18F4620-I/ML)
- Lower unit cost than PIC18F4585 for higher-memory CAN nodes (לעומתPIC18F4480-I/ML)
הערות תכנון
The 44-pin QFN (ML) package has an exposed thermal pad on the underside that must be soldered to a PCB pad for both thermal dissipation and electrical ground connection. Per the Microchip 39626e datasheet, fabricate a thermal-pad copper pour of at least 1 square inch with an array of 0.3 mm thermal vias connecting the top pad to the bottom ground plane. Inadequate exposed-pad soldering raises junction-to-ambient thermal resistance and can cause thermal-shutdown events at high CPU activity. Keep decoupling capacitors (0.1 uF ceramic) within 3 mm of every VDD pin.
The PIC18F4685-I/ML supports a wide 2.0-5.5 V supply, but ADC accuracy and ECAN bus performance depend on a clean, well-regulated rail. Use a 10 uF bulk capacitor plus a 0.1 uF ceramic near each VDD/AVDD pin. For noise-sensitive designs, route VDD and AVDD through ferrite beads to isolate analog from digital noise. The nanoWatt Technology power-management modes (Sleep, Idle, Low-Voltage Sleep) drop quiescent current below 1 uA; configure the appropriate mode by clearing/setting the IDLEN and SCS0/1 bits in the OSCCON register.
ECAN bus signals (RD4/ECANRX, RD5/ECANTX) require a 5 V tolerant CAN transceiver such as the MCP2551 or TCAN334G between the MCU and the bus. Place the transceiver within 20 mm of the MCU pins to keep stub length below 1/10 of the CAN bit time. Add a 120 ohm termination resistor at each end of the bus, not at every node, and use shielded twisted-pair cable for industrial EMC compliance. For high-speed 1 Mbit/s CAN, ensure the oscillator accuracy is within +/-0.5% so the CAN bit timing is reliable.
Do not configure the ICD/ICSP pins (RB5/PGM, RB6/PGC, RB7/PGD) as outputs when designing for in-circuit programming - many designs lock themselves out of reprogramming by driving these pins low in the application. The MCLR pin must be pulled high through a 10 kohm resistor with a 100 nF decoupling cap to ground for clean reset behavior. Avoid leaving ADC channels floating - tie unused analog inputs to either VSS or VDD to prevent injected-current leakage. Finally, never write to Flash on a Brown-Out Detect event without verifying the BOR voltage threshold is set appropriately.
For mixed-signal designs using the internal ADC, separate the analog ground (AVSS) and digital ground (VSS) planes on the PCB and join them at a single point under the MCU exposed pad. Route the ADC reference voltage (VREF+/VREF-) traces as wide, short pairs to minimize input-referred noise. Place the 40 MHz crystal or resonator within 5 mm of the OSC1/OSC2 pins with guard traces around it to avoid coupling digital noise into the oscillator. Use Microchip's MPLAB X IDE with the XC8 compiler and PICkit 5 debugger for development; configure configuration bits in the IDE rather than in code to avoid boot failures.
מידע על תאימות
RoHS compliant per Microchip product page. Industrial-grade -I suffix (not AEC-Q100 qualified); for automotive safety-critical ECUs, migrate to AEC-Q100 qualified PIC18F K-series or dsPIC33 family.
