PIC18F4431-I/ML - 8-Bit 40MHz 16KB Flash MCU 44-QFN | Microchip
MPN: PIC18F4431-I/ML ✓ Hoạt độngPIC18F4431-I/ML Tóm tắt
What is a PIC18F microcontroller? A PIC18F is a high-performance 8-bit CMOS Flash microcontroller family from Microchip Technology, architected around an enhanced RISC instruction set. PIC18F devices occupy a tier above PIC16F parts in Microchip's product hierarchy: 8-bit microcontroller -> Flash MCU -> PIC18 family -> enhanced Flash MCU with nanoWatt technology. The family is widely deployed in consumer, industrial, and automotive subsystems where deterministic real-time control, low sleep current, and on-chip analog peripherals reduce external component count.
Key features of the PIC18F4431 include 16KB Flash with 10,000 erase/write cycles endurance, 768 bytes of RAM, 256 bytes of EEPROM, nanoWatt power management with multiple idle/sleep modes, and a Power Control PWM (PCPWM) module with up to eight complementary outputs and programmable dead-band delay. The 10-bit ADC offers 9 channels with auto-acquisition, and the device includes a USART, MSSP (SPI/I2C), and four 16-bit timers suitable for closed-loop control loops.
The PIC18F4431's 44-QFN package exposes 34 I/O lines and integrates a high-current sink/source capability of 25 mA per pin, which simplifies driving power MOSFET bridges through external gate drivers. The 8-bit Harvard architecture executes most instructions in one cycle (4-clock Tcy) at 40 MHz, giving 10 MIPS throughput. Internal Phase-Locked Loop (PLL) options multiply the external crystal up to the operating frequency, while the nanoWatt features reduce standby current below typical battery-monitoring thresholds.
Typical applications include BLDC and PMSM motor control, three-phase UPS and inverter stages, switch-mode power supply (SMPS) digital control loops, industrial fan and pump drives, HVAC compressor controllers, and low-end servo positioning. The integrated PCPWM block eliminates an external PWM controller, reducing BOM cost and PCB area in motor-drive designs.
When designing with this device, ensure the Vdd/Vss decoupling network uses a 100 nF ceramic capacitor placed within 5 mm of each power pin pair, and a 10 uF bulk tantalum or aluminum-polymer capacitor on each power rail. For high-noise motor environments, add a ferrite bead on the supply line. The MCLR reset pin should be pulled up to Vdd through a 10 kohm resistor, with the optional MCLR capacitor omitted if in-circuit debugging (ICD) is required.
This page synthesizes distributor pricing, drop-in alternatives from the PIC18F family, and practical design notes not found in the manufacturer datasheet alone.
Bộ thay thế dễ dàng lắp đặt cho PIC18F4431-I/ML — cùng gói, chân-to-chân tương thích. Các bộ phận yêu cầu hàn PCB bị loại trừ.
Các biến thể trong loạt này
Các mẫu cùng loạt có thể lắp đặt dễ dàng tương thích với PIC18F4431-I/ML (cùng hình factor và footprint) — khác nhau ở Operating Temperature, Core Architecture, Package, Communication, ADC.
PIC18F4331-I/ML
✅ Drop-InLiên hệ để biết giá
Xem tài liệu →PIC18F2431-I/ML
✅ Drop-In📋 Tham chiếu thay thế (không có trong danh mục)
PIC18F2331-I/ML
✅ Drop-In📋 Tham chiếu thay thế (không có trong danh mục)
PIC18F4431-I/ML Tỷ lệ tối đa & tính chất điện
| Core Architecture | PIC18 8-bit RISC |
| Program Memory Type | Enhanced Flash |
| Program Memory Size | 16 KB (8K x 16) |
| RAM Size | 768 bytes |
| EEPROM Size | 256 bytes |
| Maximum CPU Clock | 40 MHz |
| Instruction Throughput | 10 MIPS |
| Supply Voltage (Vdd) | 4.2 V to 5.5 V |
| I/O Pins | 34 |
| ADC | 10-bit, 9 channels |
| PWM Module | Power Control PWM, 8 complementary outputs with programmable dead-band |
| Communication | 1x USART, 1x MSSP (SPI / I2C) |
| Timers | 4 x 16-bit |
| Hộp | 44-pin QFN (8x8 mm) |
| Nhiệt độ hoạt động | -40 C to +85 C (Industrial, -I suffix) |
| Kiểu lắp đặt | Surface Mount |
| Cấp MSL | 1 (unlimited) |
| Trạng thái RoHS | Compliant |
Cấu hình chân PIC18F4431-I/ML
| Chân 1 | MCLR — Master Clear (reset) input, internal pull-up, drive low to reset |
| Chân 2 | OSC1/RA7 — External oscillator input / GPIO RA7 |
| Chân 3 | OSC2/RA6 — External oscillator output / GPIO RA6 |
| Chân 4 | RA0/AN0 — GPIO RA0 / ADC input AN0 |
| Chân 5 | RA1/AN1 — GPIO RA1 / ADC input AN1 |
| Chân 6 | RA2/AN2 — GPIO RA2 / ADC input AN2 |
| Chân 7 | RA3/AN3 — GPIO RA3 / ADC input AN3 |
| Chân 8 | RA4/AN4 — GPIO RA4 / ADC input AN4 |
| Chân 9 | RA5/AN5 — GPIO RA5 / ADC input AN5 |
| Chân 10 | Vss — Ground reference |
| Chân 11 | VDD — Positive supply (4.2 V to 5.5 V) |
| Chân 12 | RB0/INT0 — GPIO RB0 / external interrupt 0 |
| Chân 13 | RB1/INT1 — GPIO RB1 / external interrupt 1 |
| Chân 14 | RB2/INT2 — GPIO RB2 / external interrupt 2 |
| Chân 15 | RB3/CCP2 — GPIO RB3 / Capture-Compare-PWM 2 |
| Chân 16 | RB4 — GPIO RB4 |
| Chân 17 | RB5 — GPIO RB5 |
| Chân 18 | RB6/PGC — GPIO RB6 / ICSP clock |
| Chân 19 | RB7/PGD — GPIO RB7 / ICSP data |
| Chân 20 | Vss — Ground reference |
| Chân 21 | VDD — Positive supply (4.2 V to 5.5 V) |
| Chân 22 | RC0/T1OSO — GPIO RC0 / Timer1 oscillator output |
| Chân 23 | RC1/T1OSI — GPIO RC1 / Timer1 oscillator input |
| Chân 24 | RC2/CCP1 — GPIO RC2 / Capture-Compare-PWM 1 |
| Chân 25 | RC3/SCK/SCL — GPIO RC3 / MSSP clock (SPI SCK / I2C SCL) |
| Chân 26 | RC4/SDI/SDA — GPIO RC4 / MSSP data (SPI SDI / I2C SDA) |
| Chân 27 | RC5/SDO — GPIO RC5 / MSSP data out (SPI SDO) |
| Chân 28 | RC6/TX/CK — GPIO RC6 / USART asynchronous TX or synchronous clock |
| Chân 29 | RC7/RX/DT — GPIO RC7 / USART asynchronous RX or synchronous data |
| Chân 30 | Vss — Ground reference |
| Chân 31 | VDD — Positive supply (4.2 V to 5.5 V) |
| Chân 32 | RD0/PWM0 — GPIO RD0 / Power Control PWM output 0 |
| Chân 33 | RD1/PWM1 — GPIO RD1 / Power Control PWM output 1 |
| Chân 34 | RD2/PWM2 — GPIO RD2 / Power Control PWM output 2 |
| Chân 35 | RD3/PWM3 — GPIO RD3 / Power Control PWM output 3 |
| Chân 36 | RD4/PWM4 — GPIO RD4 / Power Control PWM output 4 |
| Chân 37 | RD5/PWM5 — GPIO RD5 / Power Control PWM output 5 |
| Chân 38 | RD6/PWM6 — GPIO RD6 / Power Control PWM output 6 |
| Chân 39 | RD7/PWM7 — GPIO RD7 / Power Control PWM output 7 |
| Chân 40 | Vss — Ground reference |
| Chân 41 | VDD — Positive supply (4.2 V to 5.5 V) |
| Chân 42 | RE0/PWM8 — GPIO RE0 / Power Control PWM output 8 |
| Chân 43 | RE1/PWM9 — GPIO RE1 / Power Control PWM output 9 |
| Chân 44 | RE2/PWM10 — GPIO RE2 / Power Control PWM output 10 |
Ứng dụng tiêu biểu
PIC18F4431-I/ML phù hợp cho 6 Áp dụngs: BLDC Motor Control, Switch-Mode Power Supply (SMPS) Digital Control, Industrial Fan and Pump Drives, HVAC Compressor Controllers, Uninterruptible Power Supply (UPS) Inverter Stage, Low-End Servo and Positioning Controllers.
BLDC Motor Control
The PIC18F4431-I/ML is purpose-built for BLDC and PMSM motor control because its Power Control PWM module provides up to eight complementary outputs with programmable dead-band delay that prevents shoot-through in a three-phase inverter bridge. With 10 MIPS throughput from the 40 MHz oscillator, the CPU can run a sensorless back-EMF zero-crossing algorithm and a closed-loop PI speed controller at typical PWM frequencies of 20 to 50 kHz while leaving headroom for housekeeping tasks. The 10-bit ADC with 9 channels samples phase currents and DC-bus voltage simultaneously, and the high-current 25 mA I/O pins simplify interfacing to gate-driver ICs such as the IR2104 or MCP14E1. Compared with a discrete analog control loop, the integrated solution reduces BOM count and PCB area.
Được đề xuất
Switch-Mode Power Supply (SMPS) Digital Control
The PIC18F4431-I/ML's high-resolution 14-bit PCPWM and fast 10 MIPS CPU make it suitable as a digital controller for isolated and non-isolated SMPS topologies such as half-bridge, full-bridge, and active-clamp forward converters. The ADC samples the output voltage and primary current at the start of each PWM cycle, and the firmware implements peak-current-mode or average-current-mode control with slope compensation. With 16 KB of Flash, complex state machines, soft-start sequencing, and supervisory housekeeping fit comfortably; 768 bytes of RAM is adequate for control variables, and 256 bytes of EEPROM store calibration constants. Compared with analog UC3842-style controllers, the digital loop enables adaptive compensation and telemetry.
Được đề xuất
Industrial Fan and Pump Drives
Variable-frequency drives for industrial fans and centrifugal pumps benefit from the PIC18F4431-I/ML because it integrates the three-phase PWM, ADC feedback, and supervisory logic in one IC. The PCPWM generates the six PWM signals required for a three-phase IGBT inverter at carrier frequencies up to about 25 kHz, while the ADC measures the DC bus voltage and phase currents for sensorless V/Hz or space-vector-modulation control. The 34 I/O pins cover enable inputs, fault outputs, tachometer feedback, and a USART that links to a Modbus RTU master. Compared with a discrete DSP plus logic-IC implementation, this MCU reduces system cost while keeping firmware updateable in the field.
Được đề xuất
HVAC Compressor Controllers
In HVAC compressor and blower drives, the PIC18F4431-I/ML provides deterministic motor control plus room for safety and communications firmware. The 16 KB Flash holds sensorless sinusoidal commutation tables, current-limit ramps, and a UART-based service interface, while the 768 B RAM covers state variables and the 256 B EEPROM stores compressor-matching parameters across power cycles. The industrial -40 C to +85 C temperature range handles under-hood or rooftop-unit environments. Compared with a fixed-function motor controller, the PIC18F4431-I/ML adds soft-start profiles, brown-out handling, and field-reprogrammable tuning without hardware changes.
Được đề xuất
Uninterruptible Power Supply (UPS) Inverter Stage
Low-to-medium power UPS inverter stages use the PIC18F4431-I/ML to generate the AC sine output through the PCPWM module driving an H-bridge or three-phase IGBT bridge. The ADC senses battery voltage, output current, and temperature, while the firmware implements a digital sine-PWM generator and a closed-loop RMS voltage regulator. With 16 KB Flash the device can hold multiple output-voltage profiles (120 V / 230 V, 50 Hz / 60 Hz) selectable through I/O, and 256 B EEPROM stores the calibration constants per profile. Compared with pure analog oscillator designs, the digital approach delivers better THD and faster load-step response.
Được đề xuất
Low-End Servo and Positioning Controllers
For small stepper or DC servo positioning controllers in industrial automation, the PIC18F4431-I/ML combines sufficient CPU bandwidth, PWM, ADC, and USART in a single 44-QFN device. The PCPWM drives a single H-bridge at up to 50 kHz with directional logic, the ADC reads a potentiometer or encoder feedback, and the USART links to a PLC or HMI. With 34 I/O pins the controller handles limit switches, brake control, and indicator LEDs without a logic expander. Compared with a discrete analog servo amplifier, this MCU offers programmable acceleration/deceleration ramps and absolute positioning from EEPROM-stored setpoints.
Được đề xuất
Tóm tắt các sản phẩm được đề xuất
Dữ liệu tham khảo kỹ thuật cho PIC18F4431-I/ML — so sánh, hướng dẫn thiết kế và thông tin tuân thủ.
Hướng dẫn chọn lựa
So sánh với các sản phẩm thay thế
| Tham số | Sản phẩm này | PIC18F4331-I/ML | PIC18F2431-I/ML | PIC18F2331-I/ML |
|---|---|---|---|---|
| Package | 44-QFN (8x8 mm) | 44-QFN (8x8 mm) - same | 28-QFN (6x6 mm) - smaller, drop-in only for I/O subset | 28-QFN (6x6 mm) - smaller, drop-in only for I/O subset |
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Program Memory | 16 KB Flash | 8 KB Flash (-50%) | 16 KB Flash (same) | 8 KB Flash (-50%) |
| RAM | 768 bytes | 768 bytes (same) | 768 bytes (same) | 768 bytes (same) |
| Maximum CPU Clock | 40 MHz / 10 MIPS | 40 MHz / 10 MIPS (same) | 40 MHz / 10 MIPS (same) | 40 MHz / 10 MIPS (same) |
| Supply Voltage | 4.2 V to 5.5 V | 4.2 V to 5.5 V (same) | 4.2 V to 5.5 V (same) | 4.2 V to 5.5 V (same) |
| I/O Pins | 34 | 34 (same) | 24 (-29%) | 24 (-29%) |
| PWM Module | PCPWM, 8 complementary outputs | PCPWM, 8 complementary outputs (same) | PCPWM, 6 complementary outputs | PCPWM, 6 complementary outputs |
| ADC | 10-bit, 9 channels | 10-bit, 9 channels (same) | 10-bit, 5 channels | 10-bit, 5 channels |
Bảo phân biệt quan trọng
- Half-memory variant on identical 44-QFN footprint (vsPIC18F4331-I/ML)
- Integrated Power Control PWM for three-phase inverters (vsPIC18F458-I/ML)
- More I/O and more PWM channels than 28-pin family members (vsPIC18F2431-I/ML)
Ghi chú thiết kế
Place a 100 nF ceramic decoupling capacitor within 5 mm of every Vdd/Vss pin pair on the PIC18F4431-I/ML, and add a single 10 uF bulk tantalum or aluminum-polymer capacitor on each power rail. AVDD must be tied directly to VDD with its own local 100 nF bypass to avoid ADC reference noise. For motor-drive boards with high dI/dt events, a ferrite bead on the supply line reduces conducted noise from the power stage entering the MCU supply. These practices typically keep Vdd ripple below 50 mV peak-to-peak.
The 44-QFN exposed thermal pad (EP) on the PIC18F4431-I/ML must be soldered to a continuous ground plane for both electrical performance and thermal dissipation; missing or partial EP soldering can cause device malfunction and overtemperature shutdown. Use a via-array pattern of 9 to 16 thermal vias (0.3 mm drill, 0.6 mm pitch) under the EP to spread heat into inner copper layers. The QFN has 0.65 mm pitch, so PCB fabrication should target 4 mil trace/space with solder mask-defined pads to avoid tombstoning on small passive components.
When using the PCPWM module, always program a non-zero dead-band delay before enabling the complementary outputs, otherwise shoot-through can damage the external MOSFET bridge. The PIC18F4431's BOR (brown-out reset) is factory-trimmed to a specific threshold and should not be disabled in motor applications because a low-Vdd event can corrupt Flash and EEPROM. Estimate: at Vdd=5 V and 25 mA source current, sourcing 34 I/O simultaneously would draw 850 mA, which exceeds the absolute maximum I/O source specification, so outputs must be toggled in groups to limit total pin current.
Keep the high-current PWM traces (RD0-RD7, RE0-RE2) short and wide to minimize switching transients, and route the analog ADC inputs (AN0-AN8) away from the PWM traces to avoid capacitive coupling. The MCLR pin should be pulled up to VDD through a 10 kohm resistor; if in-circuit debugger (ICD) is required, omit the optional MCLR capacitor and route the ICSP clock/data lines (RB6/PGC, RB7/PGD) directly to the debug header. Place a 4.7 kohm to 10 kohm pull-up on RB6 and RB7 only if no ICD is connected in production.
Thông tin tuân thủ
RoHS and REACH compliant per Microchip product page; matte-tin lead finish on /ML package. Not AEC-Q100 qualified - for automotive, choose a Q-grade part number. Halogen-free per Microchip environmental certification.
