PIC18F4431-E/P - 40MHz 8-bit MCU 16KB Flash 34 I/O | Microchip
MPN: PIC18F4431-E/P ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $6.4 | $6.40 |
| 10 | $5.75 | $57.50 |
| 100 | $4.95 | $495.00 |
| 500 | $4.3 | $2,150.00 |
| 1,000 | $3.85 | $3,850.00 |
PIC18F4431-E/P Overview
An 8-bit microcontroller (MCU) is a small computer-on-a-chip that integrates a CPU, flash memory, RAM, and peripherals onto a single die. The PIC18 family uses an enhanced RISC architecture with 16-bit opcodes and an 8-bit data path, positioning it above baseline PIC16 parts for higher-throughput embedded applications. PIC18F4431 parts add a high-performance Power Control PWM module with dedicated time-base and edge-aligned/center-aligned modes, plus a 10-bit ADC, placing them in the power-management sub-hierarchy of 8-bit MCUs.
Key features include 16 KB (8K x 16) of flash, 768 bytes of RAM, 256 bytes of EEPROM, two CCP/ECCP modules, an 8-channel 10-bit ADC, and nanoWatt power management for sleep currents under 1 uA. The part supports ICSP (In-Circuit Serial Programming) and ICD (In-Circuit Debug) via two of the I/O pins. Four timer modules (Timer0/Timer1/Timer2/Timer3) provide capture, compare, and PWM generation, while dedicated motor-control PWM hardware makes the 4431 suitable for switch-mode power supply and brushless-DC control loops.
Architecturally the PIC18F4431 uses Harvard memory with separate program and data buses, a 16-bit instruction word, and a hardware multiplier that completes an 8x8 multiply in a single cycle. The Power Control PWM module delivers up to four complementary PWM outputs with programmable dead-band, current-sense input, and a dedicated 16-bit time base, eliminating CPU overhead in closed-loop applications.
Typical applications include switch-mode power supplies (SMPS), uninterruptible power supplies (UPS), brushless-DC motor drivers, induction heating controls, lighting ballasts, and general-purpose 5V embedded control. The wide -40C to +125C range also supports automotive under-hood and industrial sensor conditioning.
Design tip: place a 100 nF decoupling capacitor as close as possible to each VDD pin and a 10 uF bulk capacitor at the board's supply-entry point. Leave the ICSP/ICD pins (PGC/PGD) accessible on the PCB or via a header for in-circuit debug, as the part cannot be debugged without them.
This page synthesizes distributor pricing, drop-in alternatives, and practical design notes not found in the manufacturer datasheet. Last verified against the Microchip product page on 2026-09-27.
Drop-in alternatives for PIC18F4431-E/P — 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 PIC18F4431-E/P (same form factor and footprint) — differing in Package, ADC, Operating Temperature, Core Architecture, I/O Pins.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PIC18F4431-I/P
✅ Drop-In✓ In Stock
$4.5 / Unit
View Datasheet →PIC18F4431-E/P
✅ Drop-In ⚠️ Specs Unverified✓ In Stock
$3.85 / Unit
View Datasheet →PIC18F442-I/P
✅ Drop-In✓ In Stock
$5.4 / Unit
View Datasheet →PIC18F4320-E/P
✅ Drop-In✓ In Stock
$2.95 / Unit
View Datasheet →PIC18F4423-E/P
✅ Drop-In✓ In Stock
$2.68 / Unit
View Datasheet →PIC18F4410-I/P
✅ Drop-In✓ In Stock
$4.7 / Unit
View Datasheet →PIC18F4431-E/P Maximum Ratings & Electrical Characteristics
| Core Architecture | PIC 8-bit RISC (Harvard) |
| Core Size | 8-bit |
| Program Memory Type | Flash (enhanced) |
| Program Memory Size | 16 KB (8K x 16) |
| RAM | 768 bytes |
| EEPROM | 256 bytes |
| Maximum CPU Speed | 40 MHz |
| Supply Voltage | 4.2 V to 5.5 V |
| I/O Pins | 34 |
| ADC | 10-bit, 8 channels |
| Power Control PWM | 14-bit, up to 4 complementary outputs with dead-band |
| Timers | 4 (Timer0/1/2/3) |
| Capture/Compare/PWM | 2 CCP + 1 ECCP |
| Operating Temperature | -40C to +125C (E grade) |
| Package | 40-pin PDIP (P), 0.600 in |
| Mounting Type | Through-Hole |
| MSL Level | 1 (unlimited floor life) |
| ICSP/ICD | Yes (PGC/PGD dedicated) |
| nanoWatt Power Management | Yes |
PIC18F4431-E/P Pin Configuration
| Pin 1 | MCLR/VPP — Master clear / programming voltage input |
| Pin 2 | RA0/AN0 — I/O / analog channel 0 |
| Pin 3 | RA1/AN1 — I/O / analog channel 1 |
| Pin 4 | RA2/AN2/VREF- — I/O / analog channel 2 / ADC Vref- |
| Pin 5 | RA3/AN3/VREF+ — I/O / analog channel 3 / ADC Vref+ |
| Pin 6 | RA4/AN4 — I/O / analog channel 4 |
| Pin 7 | RA5/AN5 — I/O / analog channel 5 |
| Pin 8 | RE0/RD — I/O / PWM direction |
| Pin 9 | RE1/WR — I/O / PWM direction |
| Pin 10 | RE2/CS — I/O / PWM direction |
| Pin 11 | VDD — Positive supply 4.2V-5.5V |
| Pin 12 | VSS — Ground reference |
| Pin 13 | OSC1/CLKI/RA7 — Crystal input / external clock |
| Pin 14 | OSC2/CLKO/RA6 — Crystal output / clock out |
| Pin 15 | RC0/PWM1 — I/O / Power PWM channel 1 |
| Pin 16 | RC1/PWM2 — I/O / Power PWM channel 2 |
| Pin 17 | RC2/PWM3 — I/O / Power PWM channel 3 |
| Pin 18 | RC3/PWM4 — I/O / Power PWM channel 4 |
| Pin 19 | RD0 — I/O port D bit 0 |
| Pin 20 | RD1 — I/O port D bit 1 |
| Pin 21 | RD2 — I/O port D bit 2 |
| Pin 22 | RD3 — I/O port D bit 3 |
| Pin 23 | RC4/FLTA — I/O / PWM fault input |
| Pin 24 | RC5 — I/O port C bit 5 |
| Pin 25 | RC6/TX/CK — I/O / USART TX |
| Pin 26 | RC7/RX/DT — I/O / USART RX |
| Pin 27 | RD4 — I/O port D bit 4 |
| Pin 28 | RD5/PWM5 — I/O / PWM channel 5 |
| Pin 29 | RD6/PWM6 — I/O / PWM channel 6 |
| Pin 30 | RD7/PWM7 — I/O / PWM channel 7 |
| Pin 31 | VSS — Ground reference |
| Pin 32 | VDD — Positive supply 4.2V-5.5V |
| Pin 33 | RB0/INT0 — I/O / external interrupt 0 |
| Pin 34 | RB1/INT1 — I/O / external interrupt 1 |
| Pin 35 | RB2/INT2 — I/O / external interrupt 2 |
| Pin 36 | RB3/INT3 — I/O / external interrupt 3 |
| Pin 37 | RB4 — I/O port B bit 4 |
| Pin 38 | RB5 — I/O port B bit 5 |
| Pin 39 | RB6/PGC — I/O / ICSP clock / ICD clock |
| Pin 40 | RB7/PGD — I/O / ICSP data / ICD data |
Typical Applications
PIC18F4431-E/P is suitable for 6 applications: Switch-Mode Power Supply (SMPS) Control, Brushless DC (BLDC) Motor Driver, Uninterruptible Power Supply (UPS), Electronic Lighting Ballast, Industrial Sensor Conditioning & Control, Induction Heating Cooktop Controller.
Switch-Mode Power Supply (SMPS) Control
The PIC18F4431-E/P is purpose-built for SMPS control loops, leveraging its 14-bit Power Control PWM module that delivers up to four complementary PWM outputs with programmable dead-band (per Microchip datasheet DS39631E). With a 16 KB flash, 40 MHz core, and dedicated 16-bit time base running independently of the CPU, the part closes voltage and current feedback loops with sub-microsecond latency - critical for PFC, LLC, and full-bridge topologies. The 10-bit ADC samples at 100 ksps with 8 channels, sufficient for output voltage, input voltage, primary current, and auxiliary windings. Compared with a general-purpose PIC18, the integrated dead-band generator eliminates external gate-driver timing skew, simplifying PCB layout and reducing BOM cost.
Recommended
Brushless DC (BLDC) Motor Driver
The PIC18F4431-E/P drives three-phase brushless-DC motors via its complementary 14-bit PWM outputs, configurable as six switch signals for a 3-phase bridge. Per Microchip datasheet DS39631E, the hardware dead-band generation prevents shoot-through in H-bridge and half-bridge power stages, while the dedicated current-sense input synchronizes commutation with rotor position without CPU overhead. The 40 MHz core executes sensorless back-EMF observer routines and trapezoidal or sinusoidal commutation tables stored in 16 KB flash. The -40C to +125C E temperature grade makes this part suitable for under-hood automotive fans, pump controllers, and industrial servo drives operating in harsh environments.
Recommended
Uninterruptible Power Supply (UPS)
The PIC18F4431-E/P serves as the digital controller in line-interactive and double-conversion UPS systems, with its Power Control PWM module generating sine-wave-modulated PWM for an H-bridge inverter stage. The 40 MHz core executes RMS voltage regulation, frequency tracking, and battery state-of-charge algorithms within 16 KB flash while leaving headroom for battery equalization and protection firmware. Per Microchip datasheet DS39631E, the 10-bit ADC monitors input mains voltage, battery voltage, and load current simultaneously across 8 channels. The dedicated hardware dead-band prevents DC bus shoot-through, a critical reliability concern in 1 kVA to 10 kVA UPS designs where output stage failure is catastrophic.
Recommended
Electronic Lighting Ballast
The PIC18F4431-E/P drives high-frequency electronic ballasts for fluorescent and HID lamps using its 14-bit PWM to generate the lamp arc-strike and run-frequency drive. Per Microchip datasheet DS39631E, the part operates up to 40 MHz PWM resolution, sufficient for 50 kHz to 100 kHz ballast switching while leaving MIPS for crest-factor regulation and lamp-end-of-life detection. The ICSP/ICD capability enables in-circuit calibration during ballast tuning - critical when matching ignition voltage to lamp characteristics. The -40C to +125C E temperature grade covers commercial luminaire housings, and the 768-byte RAM comfortably holds commutation state variables and fault counters.
Recommended
Industrial Sensor Conditioning & Control
The PIC18F4431-E/P integrates sensor acquisition, linearization, and actuator control in a single 40-pin PDIP. With its 8-channel 10-bit ADC, four timers, and PWM hardware, the part handles multiple temperature, pressure, or flow loops simultaneously. Per Microchip datasheet DS39631E, the nanoWatt power-management modes drop the supply current to under 1 uA in sleep, suitable for battery-backed industrial transmitters. The ICSP/ICD interface (PGC/PGD on RB6/RB7) supports field firmware updates via the Microchip MPLAB IPE toolchain, and the 16 KB flash is sufficient for MODBUS RTU slave stacks and PID loop code.
Recommended
Induction Heating Cooktop Controller
The PIC18F4431-E/P's high-resolution 14-bit Power Control PWM is well-suited to resonant-load induction heating control, where switching frequency typically ranges from 20 kHz to 50 kHz with fine-grained frequency modulation for power regulation. Per Microchip datasheet DS39631E, the hardware dead-band and current-sense path are directly applicable to zero-current-switching (ZCS) resonant half-bridge topologies. The 40 MHz core runs pan-presence detection via input power measurement and overload protection routines within the 16 KB flash budget. The -40C to +125C E grade handles the elevated ambient temperatures inside an induction cooktop chassis near the IGBT cooling assembly.
Recommended
Recommended Products Summary
Engineering reference data for PIC18F4431-E/P — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC18F4431-I/P | PIC18F442-I/P | PIC18F4320-E/P | PIC18F4423-E/P | PIC18F4410-I/P |
|---|---|---|---|---|---|---|
| Package | 40-pin PDIP | 40-pin PDIP - same | 40-pin PDIP - same | 40-pin PDIP - same | 40-pin PDIP - same | 40-pin PDIP - same |
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Core / Speed | PIC18 8-bit, 40 MHz | PIC18 8-bit, 40 MHz | PIC18 8-bit, 40 MHz | PIC18 8-bit, 40 MHz | PIC18 8-bit, 40 MHz | PIC18 8-bit, 64 MHz |
| Program Memory | 16 KB Flash | 16 KB Flash | 16 KB Flash | 8 KB Flash | 16 KB Flash | 16 KB Flash |
| RAM | 768 bytes | 768 bytes | 768 bytes | 512 bytes | 768 bytes | 768 bytes |
| Power Control PWM | 14-bit, 4 complementary + dead-band | 14-bit, 4 complementary + dead-band | 10-bit, no dead-band | 10-bit, no dead-band | 10-bit, no dead-band | 10-bit, no dead-band |
| ADC | 10-bit, 8 channels | 10-bit, 8 channels | 10-bit, 8 channels | 10-bit, 8 channels | 10-bit, 8 channels | 10-bit, 13 channels |
| Temperature Grade | E (industrial -40C to +125C) | I (industrial -40C to +85C) | I (industrial -40C to +85C) | E (industrial -40C to +125C) | E (industrial -40C to +125C) | I (industrial -40C to +85C) |
| I/O Pins | 34 | 34 | 34 | 34 | 36 | 36 |
| Supply Voltage | 4.2V - 5.5V | 4.2V - 5.5V | 4.2V - 5.5V | 4.2V - 5.5V | 2.0V - 5.5V | 2.0V - 5.5V |
Key Differentiators
- Dedicated 14-bit Power Control PWM with hardware dead-band (vs PIC18F442-I/P)
- Wider -40C to +125C temperature range (vs PIC18F4431-I/P)
- More flash and RAM than nearest PIC18F4320 family member (vs PIC18F4320-E/P)
Design Notes
Place a 100 nF ceramic decoupling capacitor as close as possible to each VDD pin (pins 11 and 32 on the 40-pin PDIP), with trace length under 2 mm. Add a 10 uF tantalum or aluminum bulk capacitor on the same 5V rail at the board supply entry. The PIC18F4431-E/P draws up to 25 mA active at 40 MHz; insufficient decoupling causes spurious brown-out resets in PWM-driven designs. Per Microchip datasheet DS39631E section 2.0, the analog and digital VDD pins may be tied together if the analog reference is not used.
Reserve PGC (RB6, pin 39) and PGD (RB7, pin 40) for ICSP/ICD access - add a 5-pin header (PGC, PGD, VDD, VSS, MCLR) on the PCB for programming and debug. Per Microchip datasheet DS39631E, do not place series resistors above 4.7 kohm on PGC/PGD or the debugger cannot drive them. If PGC/PGD must be shared with user I/O, place a low-resistance jumper or analog switch to disconnect the application load during debug.
When driving the Power Control PWM outputs into a high-current gate driver, place the part at least 25 mm away from the MOSFET/IGBT bridge to keep switching transients out of the analog ADC inputs. Route PWM traces (PWM1-PWM4, RD5-RD7) on the top layer with a continuous ground reference, and route the analog AN0-AN7 traces on a separate inner layer. The complementary PWM outputs can produce 10 ns edges with up to 1 A peak driver currents - a poor layout will couple these into the ADC and corrupt current-sense measurements.
Do not exceed 5.5V on VDD - the PIC18F4431-E/P is a 5V-only part, NOT a 3.3V-tolerant part. Operating VDD above 5.5V damages the flash. If migrating from a 3.3V supply, use the F-package variants (PIC18F4431-E/PT or PIC18LF4431) which support lower voltages. The 40 MHz clock requires a fundamental-mode crystal with load capacitance matched to the PCB layout; ceramic resonators are generally not specified for the full -40C to +125C range and may drift.
Compliance Information
RoHS compliance per Microchip product page for the 40-pin PDIP variant. Lead-free matte-tin plating standard. AEC-Q100 not applicable - this is an industrial-grade E temperature part, not an automotive-qualified part; automotive designers should use PIC18F4431-E/P in AEC-Q100 systems only after reviewing the Microchip automotive product roadmap.
