PIC18F2431T-I/MM - 40MHz 8-bit MCU 16KB Flash 28-QFN | Microchip
MPN: PIC18F2431T-I/MM ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $7.5 | $7.50 |
| 10 | $6.85 | $68.50 |
| 100 | $6.1 | $610.00 |
| 500 | $5.4 | $2,700.00 |
| 1,000 | $4.75 | $4,750.00 |
| 2,500 | $4.3 | $10,750.00 |
PIC18F2431T-I/MM Overview
A microcontroller (MCU) is a single-chip computer containing a CPU, program memory (Flash/ROM), data memory (RAM), and peripheral set (timers, ADC, communication interfaces). The PIC18F family specifically adds enhanced Flash architecture, hardware multiply, C-friendly instruction set, and 16-bit instruction word. Within the broader semiconductor hierarchy, the PIC18F2431T-I/MM belongs to: microcontroller → 8-bit MCU → Flash MCU → PIC18F enhanced family. It is tailored for sensorless brushless DC motor control and other high-performance embedded applications.
Key features include 25 digital I/O pins, four timer modules (Timer0/1/2/3), a 40 MHz internal oscillator, ICSP (In-Circuit Serial Programming) debug support, and the Motion Feedback Module with Power Control PWM, ideal for variable-frequency drives. Its CMOS flash design supports >10,000 erase/write cycles and offers In-Circuit Debug capability via MPLAB ICD tools.
The device architecture follows the Harvard model with separate program and data buses, 77 instructions, 8 × 8 hardware multiplier, and 31-level hardware stack. Its nanoWatt power management suite provides multiple idle/sleep modes, enabling ultra-low standby current for battery-aware designs.
Typical applications include BLDC motor control (sensorless or hall-sensor commutation), uninterruptible power supplies (UPS), AC induction motor drives, HVAC blowers, and industrial pumps requiring high-speed control loops.
Design consideration: The 'T' suffix designates tape and reel packaging; the 'I' after the speed grade indicates the industrial temperature range (-40°C to +85°C); 'MM' is the QFN-S 28-pin package code.
This page synthesizes distributor pricing, drop-in alternatives, design notes, and pinout references that complement the Microchip datasheet for engineers specifying PIC18F2431-family parts.
Drop-in alternatives for PIC18F2431T-I/MM — same package, pin-to-pin compatible. Different-package parts requiring PCB rework are excluded.
Variants in this series
Same-series models that are drop-in compatible with PIC18F2431T-I/MM (same form factor and footprint) — differing in Package, Operating Temperature, ADC, Core Architecture, Timers.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PIC18F2331T-I/MM
✅ Drop-In✓ In Stock
$3.32 / Unit
View Datasheet →PIC18F2431-I/SO
✅ Drop-In✓ In Stock
$4.85 / Unit
View Datasheet →PIC18F2431-I/SP
✅ Drop-In ⚠️ Specs Unverified✓ In Stock
$5.49 / Unit
View Datasheet →PIC18F2431-E/SP
✅ Drop-In ⚠️ Specs Unverified✓ In Stock
$3.91 / Unit
View Datasheet →PIC18F2431T-I/MM Maximum Ratings & Electrical Characteristics
| Core Architecture | PIC18F (8-bit RISC, Harvard) |
| Program Memory (Flash) | 16 KB (8K x 16) |
| Data Memory (RAM) | 768 bytes |
| EEPROM | 256 bytes |
| Maximum CPU Speed | 40 MHz (10 MIPS) |
| Supply Voltage (Vdd) | 4.2 V to 5.5 V |
| I/O Pins | 25 |
| ADC | 10-bit, up to 9 channels |
| Timers | 4 (Timer0/1/2/3) |
| Communication | UART, SPI, I2C, CAN |
| PWM Channels | Motion Feedback Module, Power Control PWM |
| Operating Temperature | -40 C to +85 C (Industrial, 'I') |
| Package | 28-QFN-S (6x6 mm) with Exposed Pad |
| Mounting Type | Surface Mount |
| Programming/Debug | ICSP via MPLAB ICD/PICkit |
| RoHS Status | Compliant |
PIC18F2431T-I/MM Pin Configuration
| Pin 1 | RB2/INT2/CCP2 — GPIO RB2 / External Interrupt 2 / Capture-Compare 2 |
| Pin 2 | RB3/CCP1 — GPIO RB3 / Capture-Compare 1 |
| Pin 3 | RB4/FLTA — GPIO RB4 / Fault A input (MFM) |
| Pin 4 | RB5 — GPIO RB5 |
| Pin 5 | RB6/PGC — GPIO RB6 / ICSP Clock (PGC) |
| Pin 6 | RB7/PGD — GPIO RB7 / ICSP Data (PGD) |
| Pin 7 | Vdd — Core + I/O supply 4.2-5.5 V |
| Pin 8 | Vss — Ground |
| Pin 9 | OSC1/CLKIN/RA7 — Crystal input / External clock / GPIO RA7 |
| Pin 10 | OSC2/CLKOUT/RA6 — Crystal output / Clock out / GPIO RA6 |
| Pin 11 | RC0/T1OSO/T1CKI — GPIO RC0 / Timer1 oscillator out / ext clock |
| Pin 12 | RC1/T1OSI — GPIO RC1 / Timer1 oscillator in |
| Pin 13 | RC2/CCP1 — GPIO RC2 / Capture-Compare 1 |
| Pin 14 | RC3/SCL/SCK — GPIO RC3 / I2C SCL / SPI SCK |
| Pin 15 | RC4/SDI/SDA — GPIO RC4 / SPI SDI / I2C SDA |
| Pin 16 | RC5/SDO — GPIO RC5 / SPI SDO |
| Pin 17 | RC6/TX/CK — GPIO RC6 / UART TX / UART CK |
| Pin 18 | RC7/RX/DT — GPIO RC7 / UART RX / UART DT |
| Pin 19 | Vss — Ground |
| Pin 20 | Vdd — Core + I/O supply 4.2-5.5 V |
| Pin 21 | RB0/AN8 — GPIO RB0 / ADC channel 8 |
| Pin 22 | RB1/AN9 — GPIO RB1 / ADC channel 9 |
| Pin 23 | RA0/AN0 — GPIO RA0 / ADC channel 0 |
| Pin 24 | RA1/AN1 — GPIO RA1 / ADC channel 1 |
| Pin 25 | RA2/AN2/Vref- — GPIO RA2 / ADC ch2 / Vref- |
| Pin 26 | RA3/AN3/Vref+ — GPIO RA3 / ADC ch3 / Vref+ |
| Pin 27 | RA4/T0CKI — GPIO RA4 / Timer0 clock input |
| Pin 28 | RA5/AN4/SS — GPIO RA5 / ADC ch4 / SPI Slave Select |
| Pin 29 | EP (Pad) — Exposed thermal pad - connect to Vss |
Typical Applications
PIC18F2431T-I/MM is suitable for 6 applications: Sensorless BLDC Motor Control, HVAC Blower and Fan Drives, Uninterruptible Power Supply (UPS) Control, Industrial Pumps and Compressors, Small Appliance Variable-Frequency Drives, RC Hobby Servo and Robotics Drives.
Sensorless BLDC Motor Control
The PIC18F2431T-I/MM drives sensorless brushless DC (BLDC) motors via its integrated Motion Feedback Module sampling back-EMF from the off-phase and 16-bit Power Control PWM generating complementary 3-phase gate signals. In a typical e-bike or e-tool design, the part operates from 5 V, runs the main torque loop at 40 MHz (10 MIPS) with a 50 us control period, and handles zero-crossing detection in hardware rather than software.
Recommended
HVAC Blower and Fan Drives
HVAC blower applications benefit from the PIC18F2431T-I/MM's programmable PWM frequency (typical 20 kHz above audible range) and closed-loop torque control through the 10-bit ADC monitoring current. In a variable-speed furnace blower, the MCU runs at 40 MHz, integrates RPM feedback from a Hall sensor via the MFM module, and adjusts duty cycle for constant airflow across a 5 V supply rail.
Recommended
Uninterruptible Power Supply (UPS) Control
The PIC18F2431T-I/MM is well suited for small-to-medium UPS inverter control where the PIC18F2431T-I/MM synchronizes 50/60 Hz sine-wave PWM with the AC mains via zero-crossing detection and a PLL loop using the 16-bit Power Control PWM. The 16 KB Flash stores sine tables and soft-start ramps; 768 bytes RAM handle PID state; 256 bytes EEPROM store calibration constants for stable output under load steps.
Recommended
Industrial Pumps and Compressors
Submersible pumps, dosing pumps, and small compressors leverage the PIC18F2431T-I/MM's hardware multiplier (8x8), 10 MIPS throughput, and 25 I/O pins to read pressure sensors, run speed curves, and drive triacs or MOSFETs through the MFM PWM channels. Industrial-grade -40C to +85C operation lets the controller survive harsh enclosures; the QFN-S exposed pad aids thermal dissipation in sealed pump housings.
Recommended
Small Appliance Variable-Frequency Drives
Washing machines, dishwashers, and range hoods use the PIC18F2431T-I/MM for direct-drive BLDC motor control where compact size and the 28-QFN-S 6x6 mm footprint save board area. The device's 40 MHz core handles spinning, agitation, and cycle state machines while the integrated ADC reads Hall sensors at up to 100 ksps for high-bandwidth speed regulation.
Recommended
RC Hobby Servo and Robotics Drives
Robotics and drone motor controllers use the PIC18F2431T-I/MM for lightweight 8-bit closed-loop control of small brushed or BLDC servos. The 16-bit PWM resolution produces servo-grade positioning accuracy at 50 Hz update rate, while 768 bytes RAM are enough for kinematic interpolation. ICSP support speeds dev board bring-up without external bootloaders.
Recommended
Recommended Products Summary
Engineering reference data for PIC18F2431T-I/MM — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC18F2331T-I/MM | PIC18F2431-I/SO | PIC18F2431-I/SP | PIC18F2431-E/SP |
|---|---|---|---|---|---|
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Package | 28-QFN-S (MM) | 28-QFN-S (MM) - same | 28-SOIC (SO) - different, drop-in only when footprint swapped | 28-SPDIP (SP) - different, drop-in only when footprint swapped | 28-SPDIP (SP) - different, drop-in only when footprint swapped |
| Program Memory (Flash) | 16 KB | 8 KB (-50%) | 16 KB (same) | 16 KB (same) | 16 KB (same) |
| RAM | 768 bytes | 768 bytes (same) | 768 bytes (same) | 768 bytes (same) | 768 bytes (same) |
| EEPROM | 256 bytes | 256 bytes (same) | 256 bytes (same) | 256 bytes (same) | 256 bytes (same) |
| CPU Clock | 40 MHz (10 MIPS) | 40 MHz (same) | 40 MHz (same) | 40 MHz (same) | 40 MHz (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) | 4.2 V to 5.5 V (same) |
| Operating Temperature | -40C to +85C (I) | -40C to +85C (same) | -40C to +85C (same) | -40C to +85C (same) | -40C to +125C (E, extended) |
| Lifecycle Status | Active | Active | Active | Active | Active |
Key Differentiators
- Integrated Motion Feedback Module and Power Control PWM (vs PIC18F2331T-I/MM (8KB Flash))
- Industrial temperature range with motor-control-optimized peripherals (vs PIC18F2431-I/SO (28-SOIC))
- Higher-temperature operation vs industrial range (vs PIC18F2431-I/SP (28-SPDIP))
Design Notes
Place a 100 nF decoupling capacitor within 5 mm of Vdd (pin 7 and pin 20, which are bonded together internally) and a second 10 uF bulk capacitor within 25 mm. Add a separate 100 nF between Avdd and AVss if analog rails are used. According to Microchip PIC18F2431 datasheet 39609b, Vdd droop at 40 MHz with all I/O switching can exceed 200 mV without proper bypassing.
The 28-QFN-S package has an exposed thermal pad (pin 29) that MUST be soldered to a land pattern connected to a copper pour. With theta_JA around 35 C/W on a 4-layer 1 oz PCB, the junction-to-ambient rise is 1.95 C per 100 mA supply current; at 40 MHz full load (about 60 mA), this yields only ~4 C rise but a poor layout can reach 20 C and degrade ADC accuracy. Estimated: 60 mA x 4.0 V x 35 C/W = 8.4 C with exposed pad, >25 C without.
The PWM outputs driving motor gate drivers produce high di/dt events; keep gate-drive traces short (under 50 mm) and use a wide ground pour under the MFM modules. Place the analog ADC inputs (AN0-AN9) away from PWM traces by at least 5 mm or guard them with ground traces. The ICSP pins RB6/RB7 should be accessible on the PCB via an in-circuit programming header for production support.
Picking this part over PIC18LF2431 for a 3.3 V system fails - the F variant requires minimum 4.2 V. When migrating firmware from PIC18F2431 to PIC18F2331, halve your Flash usage expectations (8 KB vs 16 KB). The 'T' suffix denotes tape and reel; if you've designed for an SP tray package, request PIC18F2431-I/MM (no T) for prototype assembly. ICSP uses RB6/RB7 - never use these as outputs if debug is needed.
Compliance Information
RoHS and lead-free per Microchip product page; halogen-free status not explicitly confirmed in source data; AEC-Q100 not qualified - the standard PIC18F2431T-I/MM is industrial grade.
