PIC18F4685T-I/PT - 8-Bit MCU, 96KB Flash, ECAN, 44-TQFP | Microchip
料号： PIC18F4685T-I/PT ✓ 量产中| 数量 | 单价 | 小计 |
|---|---|---|
| 1 | $10.36 | $10.36 |
| 10 | $9.32 | $93.20 |
| 100 | $8.21 | $821.00 |
| 500 | $7.45 | $3,725.00 |
| 1,000 | $6.89 | $6,890.00 |
PIC18F4685T-I/PT 概述
A microcontroller (MCU) is a single-chip computer that contains a processor core, program memory, data memory, and peripherals. The PIC18F4685 belongs to the PIC18F enhanced family, which sits in the broader 8-bit PIC hierarchy (PIC10/12/16/18) and ultimately under the embedded controller branch of semiconductor products. The PIC18F4685T-I/PT adds Enhanced CAN, 10-bit ADC with up to 11 channels, nanoWatt power management, and a 16-bit capture/compare/PWM module, making it well suited to mid-range embedded control.
Key features of the PIC18F4685T-I/PT include 36 digital I/O pins, 10-bit ADC with 11 input channels, two Enhanced USART modules, MSSP (SPI/I2C), two Enhanced Capture/Compare/PWM (ECCP) peripherals, 10 MIPS throughput at 40 MHz, and nanoWatt power-saving modes. The ECAN module supports CAN 2.0B active with multiple receive/transmit buffers. Self-programmability under software control, Flash program memory with 100K erase/write cycles typical, and a 10-year data retention rating simplify in-field firmware updates.
Architecturally, the PIC18F4685 uses a Harvard RISC core with a modified instruction set that retains compatibility with earlier PIC16 code while adding 16-bit instructions, indexed addressing, and a linear data memory space up to 4 KB. The on-chip ECAN peripheral implements the CAN 2.0B protocol in hardware, offloading bit timing, acceptance filtering, and message buffering from the CPU and enabling real-time deterministic networking at 1 Mbit/s.
Typical applications include industrial automation with CAN-bus networking, automotive body and powertrain ECUs, building automation, HVAC controllers, medical instrumentation with CAN connectivity, sensor aggregation nodes, and CAN-to-UART/SPI bridges. The wide -40 C to +85 C industrial temperature range and nanoWatt sleep modes support always-on battery-powered designs.
When designing with this part, observe Microchip's recommended decoupling: 0.1 F ceramic on each VDD pin and bulk capacitance near the IC. The ECAN bus requires a CAN transceiver such as the MCP2551 and proper 120-ohm termination. For firmware development, use MPLAB X IDE with the XC8 compiler and the PICkit 5 or ICD 4 in-circuit debugger.
This page synthesizes distributor pricing, drop-in alternatives drawn from Microchip's PIC18F family, and practical design notes not found in the manufacturer datasheet alone, giving engineers a single reference for selecting, sourcing, and validating the PIC18F4685T-I/PT for new designs or legacy migrations.
直接替换替代料： PIC18F4685T-I/PT ——相同封装，引脚兼容。需要 PCB 改动的不同封装料号已排除。
本系列中的变体
可与以下型号直接替换的同系列型号： PIC18F4685T-I/PT （相同外形与封装尺寸） ——差异在于 Package, ADC, Program Memory (Flash), Operating Temperature, Core Architecture.
快速对比工具——选择替代料号进行并排对比：
PIC18F4685-I/PT
✅ 直接替换✓ 有现货
$5.65 / 个
查看数据手册 →PIC18F4682-I/PT
✅ 直接替换✓ 有现货
$7.85 / 个
查看数据手册 →DSPIC33EP512MC806-E/PT
✅ 直接替换✓ 有现货
$8.75 / 个
查看数据手册 →PIC18F4585-I/PT
✅ 直接替换 ⚠️ 规格未核验✓ 有现货
$5.73 / 个
查看数据手册 →PIC18F46K22-I/PT
✅ 直接替换 ⚠️ 规格未核验✓ 有现货
$2.32 / 个
查看数据手册 →PIC18F4685T-I/PT 最大额定值与电气特性
| Family | PIC18F4xxx |
| Core | 8-bit PIC RISC (Harvard) |
| Program Memory | 96 KB (48K x 16) Flash |
| RAM | 3.25 KB (3328 bytes) |
| EEPROM | 1 KB |
| Maximum Clock Speed | 40 MHz |
| Instruction Throughput | 10 MIPS |
| 电源电压 | 4.2 V to 5.5 V |
| I/O Pins | 36 |
| ADC | 10-bit, 11 channels |
| CAN Module | ECAN 2.0B active |
| UART | 2x Enhanced USART |
| SPI | 1x MSSP (SPI/I2C) |
| PWM | 2x ECCP + 1x CCP |
| 工作温度 | -40 C to +85 C (Industrial) |
| 封装 | 44-pin TQFP (10x10 mm) |
| 安装类型 | Surface Mount |
| MSL 等级 | 3 (168 hours) |
| RoHS 状态 | Compliant |
| Lead-Free | Yes |
PIC18F4685T-I/PT 引脚配置
| 引脚 1 | RC2/CCP1 — Digital I/O / Capture-Compare-PWM output 1 |
| 引脚 2 | RC3/SCK/SCL — Digital I/O / SPI clock / I2C clock |
| 引脚 3 | RC4/SDI/SDA — Digital I/O / SPI data in / I2C data |
| 引脚 4 | RC5/SDO — Digital I/O / SPI data out |
| 引脚 5 | RC6/TX1/CK1 — Digital I/O / USART1 TX / USART1 clock |
| 引脚 6 | RC7/RX1/DT1 — Digital I/O / USART1 RX / USART1 data |
| 引脚 7 | RD4/ECCP1/P1A — Digital I/O / Enhanced CCP1 / PWM output |
| 引脚 8 | RD5/P1B — Digital I/O / PWM output 1B |
| 引脚 9 | RD6/P1C — Digital I/O / PWM output 1C |
| 引脚 10 | RD7/P1D — Digital I/O / PWM output 1D |
| 引脚 11 | VSS — Ground reference |
| 引脚 12 | VDD — Positive supply 4.2 V to 5.5 V |
| 引脚 13 | OSC1/RA7 — Crystal input or digital I/O |
| 引脚 14 | OSC2/RA6 — Crystal output or digital I/O |
| 引脚 15 | RC0/T1OSO — Digital I/O / Timer1 oscillator output |
| 引脚 16 | RC1/T1OSI/CCP2 — Digital I/O / Timer1 oscillator input / CCP2 |
| 引脚 17 | RB0/INT0 — Digital I/O / External interrupt 0 |
| 引脚 18 | RB1/INT1 — Digital I/O / External interrupt 1 |
| 引脚 19 | RB2/INT2 — Digital I/O / External interrupt 2 |
| 引脚 20 | RB3/INT3 — Digital I/O / External interrupt 3 |
| 引脚 21 | RB4/KBI0 — Digital I/O / Keyboard interrupt 0 |
| 引脚 22 | RB5/KBI1 — Digital I/O / Keyboard interrupt 1 |
| 引脚 23 | RB6/KBI2/PGC — Digital I/O / Keyboard interrupt 2 / ICSP clock |
| 引脚 24 | RB7/KBI3/PGD — Digital I/O / Keyboard interrupt 3 / ICSP data |
| 引脚 25 | MCLR — Master clear reset (active low) |
| 引脚 26 | RA0/AN0 — Digital I/O / ADC input 0 |
| 引脚 27 | RA1/AN1 — Digital I/O / ADC input 1 |
| 引脚 28 | RA2/AN2/VREF- — Digital I/O / ADC input 2 / ADC reference low |
| 引脚 29 | RA3/AN3/VREF+ — Digital I/O / ADC input 3 / ADC reference high |
| 引脚 30 | RA4/T0CKI — Digital I/O / Timer0 clock input |
| 引脚 31 | RA5/AN4 — Digital I/O / ADC input 4 |
| 引脚 32 | VSS — Ground reference |
| 引脚 33 | VDD — Positive supply 4.2 V to 5.5 V |
| 引脚 34 | CANTX/RC2 — CAN transmit (shared with digital I/O) |
| 引脚 35 | CANRX/RC3 — CAN receive (shared with digital I/O) |
| 引脚 36 | RE0/RD — Digital I/O / Parallel port read |
| 引脚 37 | RE1/WR — Digital I/O / Parallel port write |
| 引脚 38 | RE2/CS — Digital I/O / Parallel port chip select |
| 引脚 39 | RD0 — Digital I/O port D bit 0 |
| 引脚 40 | RD1 — Digital I/O port D bit 1 |
| 引脚 41 | RD2 — Digital I/O port D bit 2 |
| 引脚 42 | RD3 — Digital I/O port D bit 3 |
| 引脚 43 | AVSS — Analog ground reference |
| 引脚 44 | AVDD — Analog positive supply |
典型应用
PIC18F4685T-I/PT 适用于 7 应用s: Industrial CAN-bus Automation, Automotive Body and Powertrain ECU, HVAC and Building Automation Controller, Medical Instrument Sensor Hub, Sensor Aggregation and Gateway Node, Industrial Motor Control, Embedded Data Logger.
Industrial CAN-bus Automation
The PIC18F4685T-I/PT is purpose-built for industrial CAN 2.0B networks that demand deterministic real-time communication. Its integrated ECAN module supports up to 1 Mbit/s with hardware acceptance filtering, while the 10 MIPS core handles both the application stack and the CANOpen or DeviceNet protocol. The 96 KB Flash accommodates full CANOpen stack libraries with room to spare, and 3.25 KB RAM covers receive buffer pools plus application scratch. Industrial temperature operation from -40 C to +85 C supports factory-floor deployment.
推荐
Automotive Body and Powertrain ECU
The PIC18F4685T-I/PT integrates the ECAN controller, 10-bit ADC with 11 channels, ECCP PWM, and 36 I/O, all needed for body controllers, climate modules, and sensor interface ECUs. Its 16-bit ECCP modules generate precise PWM for motor and valve control, while the dual USARTs bridge LIN or K-line diagnostics. With 96 KB Flash and self-programmability, OTA-style firmware updates are possible in fielded vehicles. Pair with an MCP2551 transceiver for the physical bus.
推荐
HVAC and Building Automation Controller
In HVAC and building automation, the PIC18F4685T-I/PT aggregates data from temperature, humidity, and air-quality sensors over its 10-bit ADC and communicates to higher-level BMS backbones via ECAN. Its 36 I/O drive relays, triacs, and 7-segment displays directly. The nanoWatt power-saving modes reduce standby consumption below 1 uA in idle states, supporting always-on nodes. Wide 4.2 V to 5.5 V supply allows direct 5 V industrial bus powering.
推荐
Medical Instrument Sensor Hub
The PIC18F4685T-I/PT serves as a low-cost sensor aggregation hub in medical instrumentation, capturing data from multiple physiological sensors via its 11-channel ADC and forwarding aggregated packets over CAN to a host controller. Its 3.25 KB RAM supports buffer management for time-series streams, while 96 KB Flash hosts proprietary signal-processing routines. The ECAN module isolates safety-critical host from peripheral noise, and the -40 C to +85 C range supports clinical environments.
推荐
Sensor Aggregation and Gateway Node
The PIC18F4685T-I/PT acts as a CAN-to-UART/SPI gateway that aggregates sensor data and bridges to upstream processors. Its dual Enhanced USARTs support LIN, RS-485, or K-line, while MSSP provides SPI or I2C master to local peripherals. The 96 KB Flash stores routing tables and protocol converters, and 3.25 KB RAM buffers inter-bus traffic. ECAN handles real-time bus arbitration at 1 Mbit/s without CPU intervention.
推荐
Industrial Motor Control
The PIC18F4685T-I/PT drives BLDC and stepper motors with its two Enhanced Capture/Compare/PWM modules, which support center-aligned, complementary, and dead-band-controlled outputs. The 40 MHz core and 10 MIPS throughput compute PI control loops with sub-microsecond latency, while the 10-bit ADC samples current shunts for closed-loop feedback. The 36 I/O handle direction control, fault inputs, and encoder feedback, and ECAN carries status messages to a centralized controller.
推荐
Embedded Data Logger
The PIC18F4685T-I/PT functions as a self-contained data logger with 1 KB internal EEPROM and SPI/I2C master ports to external Flash or FRAM. Its 96 KB Flash stores the logger firmware and 3.25 KB RAM implements ring buffers, while 36 I/O read sensors and digital inputs. The ECAN interface time-stamps events from a central network. nanoWatt sleep modes and RTC operation enable multi-year battery life on unattended loggers in remote sites.
推荐
推荐产品汇总
工程参考数据： PIC18F4685T-I/PT ——对比、设计指导和合规信息。
选型指南
与替代料对比
| 参数 | 本产品 | PIC18F4685-I/PT | PIC18F4682-I/PT | DSPIC33EP512MC806-E/PT | PIC18F4585-I/PT | PIC18F46K22-I/PT |
|---|---|---|---|---|---|---|
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Package | 44-TQFP (10x10) | 44-TQFP (10x10) | 44-TQFP (10x10) | 64-TQFP (10x10) | 44-TQFP (10x10) | 44-TQFP (10x10) |
| Program Memory | 96 KB Flash | 96 KB Flash | 80 KB Flash | 512 KB Flash | 48 KB Flash | 64 KB Flash |
| RAM | 3.25 KB | 3.25 KB | 3.25 KB | 48 KB | 3.25 KB | 3.86 KB |
| Max Clock | 40 MHz / 10 MIPS | 40 MHz / 10 MIPS | 40 MHz / 10 MIPS | 70 MHz / 70 MIPS | 40 MHz / 10 MIPS | 64 MHz / 16 MIPS |
| CAN Module | ECAN 2.0B active | ECAN 2.0B active | ECAN 2.0B active | ECAN 2.0B active | ECAN 2.0B active | None |
| Supply Voltage | 4.2 V to 5.5 V | 4.2 V to 5.5 V | 4.2 V to 5.5 V | 3.0 V to 3.6 V | 4.2 V to 5.5 V | 1.8 V to 5.5 V |
| ADC | 10-bit, 11 ch | 10-bit, 11 ch | 10-bit, 11 ch | 10/12-bit, 24 ch | 10-bit, 11 ch | 10-bit, 30 ch |
| Operating Temperature | -40 C to +85 C | -40 C to +85 C | -40 C to +85 C | -40 C to +125 C | -40 C to +85 C | -40 C to +85 C |
关键差异点
- Tape-and-reel packaging for high-volume pick-and-place assembly （对比 PIC18F4685-I/PT)
- 96 KB Flash supports CANOpen and DeviceNet stacks （对比 PIC18F4585-I/PT)
- Lower-cost alternative with same peripheral set （对比 PIC18F4682-I/PT)
设计说明
Place a 0.1 uF ceramic decoupling capacitor as close as possible to each VDD pin (pins 12, 33) and a bulk capacitor (10 uF tantalum or 4.7 uF ceramic) on the analog AVDD pin (44) with corresponding AVSS (43) ground. Per Microchip's PIC18F4685 datasheet, inadequate decoupling on AVDD causes ADC reference noise and degrades conversion accuracy by several LSBs. nanoWatt sleep modes drop supply current below 1 uA but require both decoupling networks to remain in place during wake transitions.
Route the ECAN CANTX/CANRX signals as a differential pair with 100-ohm characteristic impedance, length-matched within 5 mm, and isolated from digital switching traces. According to the Microchip PIC18F2682/2685/4682/4685 datasheet ECAN section, the CANTX/CANRX pins are shared with RC2/RC3, so assign these I/O carefully to avoid conflicts with SPI or I2C peripherals on the same ports. Place the MCP2551 transceiver within 50 mm of the MCU for signal integrity.
The PIC18F4685T-I/PT in 44-TQFP at 40 MHz consumes roughly 25 mA typical active current and 1-2 uA in sleep. Estimated: at ambient 85 C and active 25 mA from 5 V, junction-to-ambient thermal resistance for 44-TQFP is approximately 50 C/W, yielding a 6 C rise well within the -40 C to +125 C operating junction envelope. No special thermal management is required for typical embedded designs.
When migrating firmware from PIC18F4685 to PIC18F4682, ensure all Flash pages remain below the 80 KB address boundary; code that compiles above 0x14000 on the 4685 will overflow on the 4682 and silently corrupt the linker output. According to Microchip, the device ID registers must also be polled at startup to confirm the target MCU, especially on production boards where either variant may be populated.
For ICSP programming on pins 23 (PGC) and 24 (PGD), Microchip recommends 4.7 kohm pull-up resistors on PGD and PGC to keep them defined during reset and prevent unintentional entry into programming mode. According to Microchip's ICSP application note, omit these pull-ups only when an external programmer drives the bus; otherwise floating PGD/PGC may cause transient reset events in noisy industrial environments.
合规信息
RoHS compliant per Microchip product page. Not AEC-Q100 qualified - choose dsPIC33EP512MC806-E/PT for automotive Grade-1 environments. Lead-free T&R packaging only.