PIC18F4431-I/PT - 8-bit MCU, 16KB Flash, 40MHz, 44-TQFP | Microchip
MPN： PIC18F4431-I/PT ✓ 啟用中PIC18F4431-I/PT 概覽
An 8-bit microcontroller (MCU) is a single-chip computer built around an 8-bit data path that fetches, decodes, and executes instructions from on-chip program memory. Within the broader taxonomy, an 8-bit MCU sits below 16-bit and 32-bit MCUs in computational throughput, but offers deterministic interrupt latency, low cost, and ultra-low power modes that suit real-time control loops. The PIC18 family is Microchip's mid-range 8-bit line, positioned between the baseline PIC10/12/16 families and the high-performance dsPIC digital signal controllers, and is widely used in industrial, appliance, and automotive body/comfort subsystems.
Key features include nanoWatt technology power management with multiple idle and sleep modes, a 10-bit ADC with up to 9 channels and auto-acquisition, multiple serial interfaces (AUSART, MSSP SPI/I2C), and 34 digital I/O pins with interrupt-on-change capability. The integrated 14-bit PWM module supports center-aligned or edge-aligned operation, fault inputs, and dedicated trigger signals for A/D conversion, making the device particularly well suited for closed-loop motor control.
The architecture uses an 8-bit Harvard design with a 16-bit instruction word, an 8-level hardware stack, and a C compiler-friendly instruction set; the chip operates from 4.2 V to 5.5 V and is rated for the industrial -40 C to +85 C temperature range, indicated by the "-I" designator. In-circuit debug is supported via the ICD/ICSP interface, and the device is compatible with MPLAB X IDE and the MPLAB XC8 compiler.
Typical applications include BLDC and PMSM motor drives, sensored and sensorless fan/pump controllers, switched-mode power supply (SMPS) digital control loops, uninterruptible power supplies, induction-cooktop and induction-heater power stages, and HID lighting ballasts. When designing with this device, ensure that the high-current switching outputs use proper PCB thermal relief and that the PWM fault pins are wired to a hardware-safe state at power-up to avoid unintended switching events.
直接替換替代品，適用於 PIC18F4431-I/PT — 相同封裝，腳位對腳位相容。需重新設計 PCB 的不同封裝零件不列入。
此系列的變體
與下列產品可直接替換的同系列型號： PIC18F4431-I/PT （相同外形與佔位） — 差異在於 Operating Temperature, Package, Communication, ADC, Timers.
PIC18F4331-I/PT
✅ 直接替換聯絡詢價
查看資料表 →PIC18F4431-I/P
✅ 直接替換 ⚠️ 規格未經驗證聯絡詢價
查看資料表 →PIC18F2431-I/PT
✅ 直接替換 ⚠️ 規格未經驗證📋 參考替代品（不在目錄中）
PIC18F2331-I/PT
✅ 直接替換📋 參考替代品（不在目錄中）
PIC18F4331-I/ML
✅ 直接替換 ⚠️ 規格未經驗證聯絡詢價
查看資料表 →PIC18F4431-I/PT 最大額定值與電氣特性
| Core Architecture | PIC 8-bit Harvard (PIC18 enhanced) |
| Program Memory (Flash) | 16 KB (8K x 16) |
| Data RAM | 768 bytes |
| Data EEPROM | 256 bytes |
| Max CPU Clock | 40 MHz |
| Operating Voltage (VDD) | 4.2 V to 5.5 V |
| I/O Pins | 34 |
| ADC | 10-bit, up to 9 channels |
| PWM Module | 14-bit enhanced Power Control PWM, up to 8 channels |
| Timers | Multiple 8-bit and 16-bit timers (TMR0-TMR5) |
| Communication | AUSART (UART), MSSP (SPI / I2C) |
| 工作溫度 | -40 C to +85 C (Industrial) |
| 封裝 | 44-pin TQFP (PT), 10x10 mm |
| 安裝類型 | Surface Mount |
| Power-Saving Modes | nanoWatt Technology (idle/sleep modes) |
| Programming/Debug | ICSP, ICD via MPLAB tools |
PIC18F4431-I/PT 腳位配置
| 腳位 1 | RD0/PWM4 — PORTD bit 0 / PWM4 output |
| 腳位 2 | RD1/PWM5 — PORTD bit 1 / PWM5 output |
| 腳位 3 | RD2/PWM6 — PORTD bit 2 / PWM6 output |
| 腳位 4 | RD3/PWM7 — PORTD bit 3 / PWM7 output |
| 腳位 5 | RC6/TX/CK — PORTC bit 6 / AUSART TX / clock |
| 腳位 6 | RC7/RX/DT — PORTC bit 7 / AUSART RX / data |
| 腳位 7 | RC4/SDI/SDA — PORTC bit 4 / SPI SDI / I2C SDA |
| 腳位 8 | RC5/SCK/SCL — PORTC bit 5 / SPI SCK / I2C SCL |
| 腳位 9 | RC3/T0CKI/T5CKI — PORTC bit 3 / Timer0/5 clock input |
| 腳位 10 | RC2/CCP1 — PORTC bit 2 / CCP1 PWM output |
| 腳位 11 | VDD — Positive supply voltage (4.2 V to 5.5 V) |
| 腳位 12 | VSS — Ground reference |
| 腳位 13 | OSC1/CLKIN — Crystal oscillator input / external clock |
| 腳位 14 | OSC2/CLKOUT — Crystal oscillator output |
| 腳位 15 | RA0/AN0 — PORTA bit 0 / analog channel 0 |
| 腳位 16 | RA1/AN1 — PORTA bit 1 / analog channel 1 |
| 腳位 17 | RA2/AN2/VREF- — PORTA bit 2 / analog channel 2 / ADC VREF- |
| 腳位 18 | RA3/AN3/VREF+ — PORTA bit 3 / analog channel 3 / ADC VREF+ |
| 腳位 19 | RA4/AN4/T0CKI — PORTA bit 4 / analog channel 4 / T0CKI |
| 腳位 20 | RA5/AN5 — PORTA bit 5 / analog channel 5 |
| 腳位 21 | RE0/AN6 — PORTE bit 0 / analog channel 6 |
| 腳位 22 | RE1/AN7 — PORTE bit 1 / analog channel 7 |
| 腳位 23 | RE2/AN8 — PORTE bit 2 / analog channel 8 |
| 腳位 24 | RA6/OSC — PORTA bit 6 / alternate crystal |
| 腳位 25 | RA7/OSC — PORTA bit 7 / alternate crystal |
| 腳位 26 | RC0/T1CKI — PORTC bit 0 / Timer1 clock input |
| 腳位 27 | RC1/T1OSI/CCP2 — PORTC bit 1 / Timer1 oscillator / CCP2 |
| 腳位 28 | RB7/PGD — PORTB bit 7 / ICSP data |
| 腳位 29 | RB6/PGC — PORTB bit 6 / ICSP clock |
| 腳位 30 | RB5/PWM3 — PORTB bit 5 / PWM3 output |
| 腳位 31 | VSS — Ground reference |
| 腳位 32 | VDD — Positive supply voltage (4.2 V to 5.5 V) |
| 腳位 33 | RB4/PWM2 — PORTB bit 4 / PWM2 output |
| 腳位 34 | RB3/PWM1/CCP3 — PORTB bit 3 / PWM1 / CCP3 |
| 腳位 35 | RB2/PWM0 — PORTB bit 2 / PWM0 output |
| 腳位 36 | RB1/PWM1 — PORTB bit 1 / PWM1 output |
| 腳位 37 | RB0/PWM0 — PORTB bit 0 / PWM0 output |
| 腳位 38 | RD4/FLTA — PORTD bit 4 / PWM fault input A |
| 腳位 39 | RD5/PWM4 — PORTD bit 5 / PWM4 output |
| 腳位 40 | RD6 — PORTD bit 6 |
| 腳位 41 | RD7 — PORTD bit 7 |
| 腳位 42 | MCLR/VPP — Master clear (reset) / ICSP VPP |
| 腳位 43 | NC — Not connected (no internal bond on PT package) |
| 腳位 44 | NC — Not connected (no internal bond on PT package) |
典型應用
PIC18F4431-I/PT 適用於 7 應用s: BLDC / PMSM Motor Drive Control, Switched-Mode Power Supply (SMPS) Digital Control, Induction Cooktop / Induction Heating Control, HID and LED Lighting Ballast / Driver, Uninterruptible Power Supply (UPS) Controller, Sensored / Sensorless Fan and Pump Controller, Industrial Servo and Stepper Drive.
BLDC / PMSM Motor Drive Control
The PIC18F4431-I/PT is purpose-built for brushless DC and permanent-magnet synchronous motor control, thanks to its enhanced 14-bit power-control PWM with up to 8 channels and complementary outputs with programmable dead-band. With 9 channels of 10-bit ADC and 40 MIPS throughput, the MCU can execute a sensored trapezoidal commutation loop with <25 us cycle time. The dedicated PWM fault input (FLTA) supports hardware shutdown within nanoseconds of an over-current event, and the centre-aligned PWM mode eliminates the DC-bias ripple present in edge-aligned implementations. Designers typically pair it with a 3-phase gate driver such as the Microchip MCP8024 to drive MOSFET/IGBT power stages on small pumps, fans, and appliance motors.
推薦
Switched-Mode Power Supply (SMPS) Digital Control
The PIC18F4431-I/PT's high-resolution 14-bit PWM and 9-channel 10-bit ADC make it well suited as a digital control loop in isolated and non-isolated SMPS designs such as PFC boost, half-bridge LLC, and phase-shifted full-bridge converters. The PWM module supports variable-frequency operation, programmable dead-time, and ADC-trigger-on-edge, which is essential for volt-second balancing in digital controllers. Operating from 4.2 V to 5.5 V the device can be powered from an auxiliary winding on the main transformer or from a separate housekeeping rail. Typical designs pair the MCU with an IGBT/MOSFET gate driver and a current-sense amplifier to implement peak-current-mode control.
推薦
Induction Cooktop / Induction Heating Control
Induction-cooktop and induction-heater power stages demand sub-microsecond timing precision to track the resonant tank frequency and avoid catastrophic shoot-through. The PIC18F4431-I/PT's 40 MHz clock combined with its 14-bit PWM enables 100 ns resolution updates of the half-bridge drivers, while the integrated ADC samples the resonant current and tank voltage for zero-voltage-switching (ZVS) detection. The dedicated FLTA fault pin provides hardware-level shutdown on over-current, and nanoWatt sleep modes keep standby power below regulatory limits. Multiple heating zones can be time-multiplexed on the same MCU by leveraging the multi-channel PWM.
推薦
HID and LED Lighting Ballast / Driver
For high-intensity-discharge (HID) ballasts and high-power LED drivers, the PIC18F4431-I/PT provides the constant-current regulation and dimming control needed to meet automotive and street-lighting specs. The AUSART/MSSP peripherals allow DMX-512 or DALI dimming protocol integration, while the enhanced PWM generates the high-frequency switching signal for the DC-DC converter stage. The 10-bit ADC samples feedback current and ambient light sensor inputs for closed-loop brightness regulation. The industrial temperature range (-40 C to +85 C) supports outdoor luminaires and automotive headlamp modules.
推薦
Uninterruptible Power Supply (UPS) Controller
The PIC18F4431-I/PT can serve as the low-cost front-end controller in a small-to-medium UPS, monitoring line/battery voltage, temperature, and load current via its 10-bit ADC while generating the inverter PWM drive signals. The MSSP SPI/I2C ports interface with external battery-monitoring and EEPROM data-logging chips, and the AUSART provides UART telemetry to the host system. Fault detection (over-current, over-temperature, brown-out) is handled by the dedicated FLTA pin plus on-chip BOR. The 44-pin TQFP gives 34 GPIO for the multiple status LEDs and relay outputs typical of UPS panels.
推薦
Sensored / Sensorless Fan and Pump Controller
Variable-speed fans and pumps for HVAC, refrigeration, and white-goods applications benefit from the PIC18F4431-I/PT's combination of low cost, integrated 14-bit PWM, and nanoWatt idle/sleep modes. The MCU can implement sensorless back-EMF or sensored Hall-effect commutation, regulate speed via PI control on the ADC feedback, and enter micro-amp sleep mode when the system is idle. The industrial -40 C to +85 C temperature range covers under-hood and outdoor installations. The AUSART is often used for MODBUS or LIN slave comms to the system controller.
推薦
Industrial Servo and Stepper Drive
Industrial servo and stepper drives require precise current-loop PWM generation at high switching frequency, exactly the use case the PIC18F4431-I/PT was designed for. The 14-bit PWM provides the resolution to trim phase currents in microstepping stepper drives to within a few percent, while the 9-channel ADC simultaneously samples two phase currents plus supply voltage. The 40 MIPS core executes a FOC loop at 20 kHz with margin to spare for velocity/trajectory planning. The MSSP SPI port interfaces with external position-feedback encoder counters or resolver-to-digital converters.
推薦
推薦產品摘要
工程參考資料，適用於 PIC18F4431-I/PT — 比較、設計指引及合規資訊。
選型指南
與替代品比較
| 參數 | 本產品 | PIC18F4331-I/PT | PIC18F2331-I/PT | PIC18F4410-I/PT |
|---|---|---|---|---|
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Package | 44-pin TQFP (PT) 10x10 mm | 44-pin TQFP (PT) - same | 44-pin TQFP (PT) - same | 44-pin TQFP (PT) - same |
| Program Flash | 16 KB | 8 KB | 8 KB | 16 KB |
| Data RAM | 768 bytes | 768 bytes | 768 bytes | 768 bytes |
| EEPROM | 256 bytes | 256 bytes | 256 bytes | 256 bytes |
| Max CPU Clock | 40 MHz | 40 MHz | 40 MHz | 40 MHz |
| Operating Voltage | 4.2 V to 5.5 V | 4.2 V to 5.5 V | 4.2 V to 5.5 V | 4.2 V to 5.5 V |
| ADC | 10-bit, 9 channels | 10-bit, 9 channels | 10-bit, 9 channels | 10-bit, 8 channels |
| PWM Resolution | 14-bit enhanced Power Control PWM | 14-bit enhanced Power Control PWM | 14-bit enhanced Power Control PWM | 10-bit standard CCP PWM |
| Lifecycle Status | ACTIVE | ACTIVE | ACTIVE | ACTIVE |
主要差異化特點
- Twice the flash of the PIC18F4331-I/PT in the same pin-compatible package (對比PIC18F4331-I/PT)
- Dedicated 14-bit Power Control PWM vs 10-bit standard CCP on PIC18F4410 (對比PIC18F4410-I/PT)
- 9 ADC channels vs 8 on the PIC18F4410 (對比PIC18F4410-I/PT)
設計說明
Decouple both VDD pairs (pins 11/32) and the AVCC pin with 100 nF ceramic capacitors placed within 5 mm of each VDD pin, plus a bulk 10 uF tantalum or ceramic on the supply rail. The AVDD/VREF+ pair must be tied to the same regulated rail as VDD with a ferrite bead if noisy switching is present nearby. Brown-out reset (BOR) must be enabled in CONFIG1L to protect flash from low-voltage writes.
At 40 MHz switching and 5.0 V supply the PIC18F4431-I/PT dissipates under 100 mW - thermal relief is not a primary concern. However, in motor-control boards the MCU sits next to hot gate drivers and MOSFETs; place it on the opposite side of the board or behind a copper keep-out so that localized PCB heating does not push the die above 85 C. Estimated: at ambient 70 C the package self-heating is ~5 C, leaving 10 C margin to the industrial rating.
Route the crystal traces (OSC1/OSC2) symmetrically and keep them short with a grounded guard ring to avoid stray pickup. PWM output traces carrying >1 MHz should be routed away from the analog ADC inputs (AN0-AN8) and VREF traces; a 4-layer PCB with a continuous ground plane strongly recommended. The MCLR pin should be pulled up to VDD through a 10 kohm resistor with a 100 nF cap to ground for noise immunity.
Estimated: when migrating from PIC18F4331 to PIC18F4431 the only firmware change is the flash limit (8 KB vs 16 KB); however when migrating to PIC18F4410 the PWM registers differ (10-bit CCP vs 14-bit Power Control PWM) - register-level code must be re-written. Do NOT assume the FLTA fault pin is active by default - it must be enabled via the PWMCON0 register. The ICSP PGC/PGD pins (RB6/RB7) cannot be repurposed as GPIO if in-circuit debug is required.
合規資訊
RoHS compliant and lead-free per Microchip product declaration. NOT AEC-Q100 qualified - automotive designs should select the -E extended temperature variant or qualified K-series parts. REACH and conflict-minerals compliance asserted by Microchip.