PIC18F2431-E/SP - 8-bit 40MHz 16KB Flash MCU | Microchip
MPN: PIC18F2431-E/SP ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $6.12 | $6.12 |
| 10 | $5.51 | $55.10 |
| 100 | $4.84 | $484.00 |
| 500 | $4.36 | $2,180.00 |
| 1,000 | $3.91 | $3,910.00 |
PIC18F2431-E/SP Overview
A PIC18 microcontroller is a member of Microchip's 8-bit PIC (Peripheral Interface Controller) RISC architecture family, with the PIC18 sub-family adding enhanced Flash, hardware multiply, and 16-bit instruction support for computationally demanding embedded tasks. The PIC18F2431 belongs to the PIC18F2331/2431/4331/4431 family - 28/40/44-pin variants of the same silicon with progressively more I/O. These MCUs sit in the broader hierarchy: 8-bit MCU -> microcontroller -> embedded processor -> semiconductor IC.
Key features include 16 KB (8K x 16) Flash program memory with nanoWatt Technology power management, 768 bytes of RAM, 256 bytes of EEPROM, an enhanced 10-bit A/D converter with up to 9 channels on the 28-pin variant, a 14-bit resolution Power Control PWM module with up to 6 channels (3 complementary pairs), a Capture/Compare/PWM (CCP) module, two USART modules, an MSSP module for SPI / I2C, and a 16-bit timer/counter. The PIC18F2431 also provides five 8-bit timers and one 16-bit timer, watchdog timer, in-circuit debug capability, and an extended instruction set.
The PIC18F2431 architecture is built on Microchip's enhanced Harvard RISC core with 16-bit instructions and an 8-bit data path, supporting DC to 40 MHz operation (10 MIPS at 40 MHz). nanoWatt Technology dynamic power management, plus multiple low-power modes (idle, sleep, and oscillator switching) typically reduce operating current to a few mA active and below 1 uA in sleep. The motor-control-oriented PWM is the differentiator versus ordinary PIC18F parts - it drives 3-phase BLDC or 4-phase stepper bridges with dead-band control and center-aligned PWM.
Typical applications include 3-phase BLDC and PMSM motor drives, brushless DC fan and pump controllers, HVAC damper and valve actuators, small appliance motor control, and sensor signal conditioning with integrated ADC. The part is also used in industrial control, LED lighting drivers, and uninterruptible power supply control loops where deterministic PWM timing is required. Developers typically pair it with MPLAB X IDE and the XC8 compiler, programming in-circuit through ICSP.
When designing with the PIC18F2431-E/SP, observe the maximum 40 MHz Fosc limit and configure CONFIG bits for the oscillator mode, watchdog, low-voltage programming, and code protection before code generation. Decouple VDD/VSS with at least 100 nF + 10 uF bulk capacitance near the package, keep the MCLR pull-up weak if ICD is used, and reserve an ICP / ICSP header for field updates.
Drop-in alternatives for PIC18F2431-E/SP — 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 PIC18F2431-E/SP (same form factor and footprint) — differing in Package, I/O Pins, ADC, Core Architecture, Maximum CPU Speed.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PIC18F2431-I/SP
✅ Drop-In✓ In Stock
$5.49 / Unit
View Datasheet →PIC18F2331-E/SP
✅ Drop-In✓ In Stock
$4.3 / Unit
View Datasheet →PIC18F2431-E/SP Maximum Ratings & Electrical Characteristics
| Core Architecture | 8-bit PIC18 RISC (Harvard) |
| Clock Speed (Max) | 40 MHz (10 MIPS) |
| Program Memory | 16 KB (8K x 16) Flash |
| RAM | 768 bytes |
| EEPROM | 256 bytes |
| Supply Voltage | 4.2 V to 5.5 V |
| I/O Pins | 25 |
| A/D Converter | 10-bit, up to 9 channels |
| PWM Module | Power Control PWM, up to 6 channels (3 complementary pairs) |
| Communications | 2x USART, MSSP (SPI / I2C) |
| Timers | 5x 8-bit + 1x 16-bit (Timer0/1/2/3/4) |
| Package | 28-pin SPDIP (0.300-inch, skinny plastic DIP) |
| Mounting Type | Through-Hole |
| Operating Temperature | -40 C to +125 C (Extended "-E" grade) |
| Power-Saving Technology | nanoWatt Technology |
| In-Circuit Debug | ICSP / ICD support |
| Instruction Set | Enhanced PIC18 16-bit instructions, 77 instructions |
| RoHS Status | Compliant |
PIC18F2431-E/SP Pin Configuration
| Pin 1 | MCLR — Master Clear (reset) input, active low |
| Pin 2 | RA0/AN0 — Digital I/O / Analog input 0 |
| Pin 3 | RA1/AN1 — Digital I/O / Analog input 1 |
| Pin 4 | RA2/AN2/VREF- — Digital I/O / Analog input 2 / ADC VREF- |
| Pin 5 | RA3/AN3/VREF+ — Digital I/O / Analog input 3 / ADC VREF+ |
| Pin 6 | RA4/T0CKI — Digital I/O / Timer0 clock input |
| Pin 7 | RA5/AN4/SS — Digital I/O / Analog input 4 / SPI slave select |
| Pin 8 | OSC1/CLKI/RA7 — Crystal oscillator input / external clock / digital I/O |
| Pin 9 | OSC2/CLKO/RA6 — Crystal oscillator output / clock out / digital I/O |
| Pin 10 | RC0/T1OSO/T1CKI — Digital I/O / Timer1 oscillator output / Timer1 clock input |
| Pin 11 | RC1/T1OSI — Digital I/O / Timer1 oscillator input |
| Pin 12 | RC2/CCP1 — Digital I/O / Capture/Compare/PWM 1 |
| Pin 13 | RC3 — Digital I/O |
| Pin 14 | RC4 — Digital I/O |
| Pin 15 | RC5 — Digital I/O |
| Pin 16 | RC6/TX/CK — Digital I/O / USART TX / USART clock |
| Pin 17 | RC7/RX/DT — Digital I/O / USART RX / USART data |
| Pin 18 | VSS — Ground reference |
| Pin 19 | VDD — Positive power supply (4.2 V to 5.5 V) |
| Pin 20 | RB0/INT0 — Digital I/O / External interrupt 0 |
| Pin 21 | RB1/INT1 — Digital I/O / External interrupt 1 |
| Pin 22 | RB2 — Digital I/O |
| Pin 23 | RB3 — Digital I/O |
| Pin 24 | RB4 — Digital I/O |
| Pin 25 | RB5 — Digital I/O |
| Pin 26 | RB6/PGC — Digital I/O / ICSP clock |
| Pin 27 | RB7/PGD — Digital I/O / ICSP data |
| Pin 28 | VSS — Ground reference |
Typical Applications
PIC18F2431-E/SP is suitable for 6 applications: 3-Phase BLDC / PMSM Motor Drive, HVAC Damper and Valve Actuator, Small Appliance Motor Control, Industrial Fan and Pump Controller, LED Lighting Driver and Dimming Controller, Uninterruptible Power Supply Control Loop.
3-Phase BLDC / PMSM Motor Drive
The PIC18F2431-E/SP Power Control PWM module delivers up to 6 PWM channels in 3 complementary pairs with programmable dead-band and center-aligned switching - exactly what 3-phase BLDC and PMSM drives need. Operating at 40 MHz (10 MIPS) the MCU computes Park/Clark transforms or simple sinusoidal commutation within 100 us per cycle. The integrated 9-channel 10-bit ADC samples phase currents and back-EMF at the PWM reload rate for sensorless or Hall-sensor FOC control. Per Microchip's 39616D datasheet, the PWM resolution is 14-bit at typical 20 kHz switching, giving 1.22 ns edge granularity.
Recommended
HVAC Damper and Valve Actuator
The PIC18F2431-E/SP fits HVAC damper and valve actuators because its Power Control PWM can drive a brush DC or stepper positioning motor directly without an external motion controller. With 16 KB Flash and 768 bytes RAM, the firmware can host a Modbus or BACnet MS/TP stack over one of the two integrated USARTs. nanoWatt Technology reduces idle current below 1 uA, critical for always-on thermostats and 24 VAC-powered actuators. The -40 C to +125 C extended temperature range ensures operation in unconditioned plenums and rooftop unit enclosures.
Recommended
Small Appliance Motor Control
Small appliance motor control (mixers, blenders, fans, pumps) benefits from the PIC18F2431-E/SP because it integrates a 10-bit ADC, PWM, and timers in a single MCU, eliminating discrete analog-timer chips. With 40 MHz operation, closed-loop PI control of a universal or BLDC motor runs in tens of microseconds. The 25 digital I/O channels drive user-interface buttons, LED indicators, and segment displays without an I/O expander. Per Microchip's 39616D datasheet, the PIC18F2431 is the recommended choice over the PIC18F2331 when code size exceeds 8 KB for these appliance profiles.
Recommended
Industrial Fan and Pump Controller
Industrial fan and pump controllers use the PIC18F2431-E/SP to drive BLDC motors with variable speed under tachometer feedback. The MCU's Capture/Compare/PWM module handles both PWM generation and tachometer input capture on the same timer, simplifying the analog front end. The MSSP supports SPI to an external resolver or encoder chip. Two USARTs isolate the user-facing Modbus link from the debug port. The extended temperature range (-40 C to +125 C) handles outdoor and rooftop mounting.
Recommended
LED Lighting Driver and Dimming Controller
The PIC18F2431-E/SP works as an LED lighting driver with analog or PWM dimming because the 14-bit PWM provides high-resolution logarithmic dimming curves (perceived-smooth brightness). With the 10-bit ADC reading photocells and current-sense amplifiers, the MCU implements closed-loop constant-current control without a dedicated LED driver IC. nanoWatt Technology is critical for always-on drivers with Energy Star standby budgets; the part draws under 1 uA in sleep with RTC operating. The two USARTs enable DALI, 0-10 V analog, and wireless module interfaces.
Recommended
Uninterruptible Power Supply Control Loop
UPS and inverter control loops use the PIC18F2431-E/SP to generate the sine-wave SPWM driving the H-bridge power stage. The 14-bit Power Control PWM with dead-band insertion matches the typical 16 kHz to 20 kHz switching frequency used in line-interactive UPS topologies. The integrated 10-bit ADC samples battery voltage, output voltage, and current at every PWM reload to maintain regulation. With 16 KB Flash the firmware can host a sine-table generator, RMS calculator, and user LCD interface in a single MCU.
Recommended
Recommended Products Summary
Engineering reference data for PIC18F2431-E/SP — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC18F2431-I/SP | PIC18F2331-E/SP |
|---|---|---|---|
| Brand | Microchip Technology | Microchip Technology | Microchip Technology |
| Package | 28-SPDIP (0.300") | 28-SPDIP - same | 28-SPDIP - same |
| Program Memory | 16 KB Flash | 16 KB Flash | 8 KB Flash |
| RAM | 768 bytes | 768 bytes | 512 bytes |
| EEPROM | 256 bytes | 256 bytes | 256 bytes |
| Clock Speed | 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 |
| Operating Temperature | -40 C to +125 C | -40 C to +85 C | -40 C to +125 C |
| PWM Channels | 6 (3 complementary pairs) | 6 (3 complementary pairs) | 6 (3 complementary pairs) |
| ADC | 10-bit, up to 9 channels | 10-bit, up to 9 channels | 10-bit, up to 9 channels |
Key Differentiators
- Power Control PWM with complementary outputs and programmable dead-band (vs PIC18F2431-I/SP)
- 16 KB Flash vs 8 KB Flash at same package and peripheral set (vs PIC18F2331-E/SP)
- Through-hole 28-SPDIP for prototyping and repair (vs PIC18F2431T-I/SO)
Design Notes
Decouple each VDD/VSS pin pair with 100 nF ceramic plus a shared 10 uF bulk capacitor located within 5 mm of the package. The PIC18F2431 draws up to 16 mA per VDD pin transient during Flash write; insufficient bulk causes VDD droop that aborts the write. A 10 uF tantalum or polymer bulk on the rail near pin 19 is recommended for motor-control designs with high dI/dt on the power stage.
Keep the analog AVdd/AVss pair (or the dedicated VDD/VSS pins closest to the analog inputs) separated from noisy digital traces by at least 3 mm. Route the analog signals with a ground guard trace and place the ADC reference decoupling on pin 5 (VREF+) within 3 mm. For PWM outputs, keep traces short and twisted with their gate-driver return paths to limit ringing; gate-loop area should be < 0.5 cm^2 for 1 ns edges.
Configure CONFIG1L and CONFIG1H bits for the oscillator mode, watchdog timer, brown-out reset (BOR), and low-voltage programming BEFORE the first code generation. Setting the wrong oscillator configuration prevents ICSP from re-programming the device. Always verify the silicon revision (A1 vs A2) against the latest errata DS80233 - early revision parts have known PWM and ADC issues addressed by silicon A2. Disable interrupts during Flash self-write cycles (PMCON1 WR bit).
Estimated: at 40 MHz, 5 V VDD, and 16 mA active I_DD, the PIC18F2431-E/SP dissipates approximately 0.08 W. The 28-SPDIP package has theta_JA of ~50 C/W in still air, yielding a junction temperature rise of 4 C above ambient at room temperature. Even at +125 C ambient, the part remains well within the 150 C absolute maximum. Forced-air cooling is not required for the MCU itself but may be needed for the external gate drivers and MOSFETs.
Compliance Information
RoHS and REACH compliance per Microchip product page; not AEC-Q100 qualified (automotive customers should specify AEC-Q100-validated part numbers separately). Lead-free matte-tin finish on SPDIP pins.
