PIC18F4439-I/PT - 8-bit 40MHz 12KB Flash MCU w/ Motor Control | Microchip
MPN: PIC18F4439-I/PT ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $7.65 | $7.65 |
| 10 | $6.88 | $68.80 |
| 100 | $6.15 | $615.00 |
| 500 | $5.62 | $2,810.00 |
| 1,000 | $5.05 | $5,050.00 |
PIC18F4439-I/PT Overview
The PIC18F family of microcontrollers (MCU) is an 8-bit C-compiler-friendly architecture that combines high computational performance with rich on-chip peripherals. Within this family, the PIC18F4439 belongs to the PIC18FXX39 subgroup that adds a dedicated motion-feedback PWM kernel, a quadrature encoder interface, an input-capture module, and 8 channels of 10-bit analog-to-digital conversion - features that target closed-loop motor-control and switched-mode power-conversion designs.
Key specifications include 40 MHz maximum clock speed, 12 KB (typically 6K x 16) of self-programmable Flash with 256 bytes of EEPROM, 768 bytes of SRAM, 36 user I/O lines, a 10-bit ADC with eight channels, dual PWM outputs suitable for full-bridge or three-phase topologies, and an ICD (In-Circuit Debugger) interface. The device supports supply voltages from 4.2 V to 5.5 V and runs the standard PIC18 instruction set, enabling code reuse across the PIC18 portfolio.
Architecturally, the PIC18F4439 integrates the PIC18 RISC core with hardware multiply and a hardware motor-control PWM module featuring dedicated time bases and edge-aligned/center-aligned modes. This combination lets the engineer's firmware maintain deterministic control loop timing without loading the CPU, which is essential for sinusoidal commutation of single-phase induction motors and variable-frequency drives.
Typical applications include single-phase induction motor drives, appliance fan and pump controllers, BLDC and PMDC motor controllers, digital inverters, uninterruptible power supplies, switched-mode power supplies, and industrial automation boards that require deterministic PWM and precise feedback sampling.
When designing with this part, follow the datasheet decoupling guidance: place one 100 nF ceramic bypass capacitor adjacent to each VDD/VSS pair and a bulk capacitor at the regulator output. For motor-control layouts, keep the high-current switching traces away from the analog AVSS/AVDD traces to avoid ground-bounce noise coupling into the ADC result register. The PIC18F4439-I/PT is the industrial-temperature variant (-40 C to +85 C); the PIC18F4439-E/PT extends this to the extended grade while the PIC18LF4439-I/PT supports lower voltage operation for battery-aware designs.
This page consolidates datasheet specifications, distributor pricing as of 2026-09-27, and verified drop-in alternatives from Microchip's PIC18F family so that engineers can make a faster sourcing and design-in decision than by reading dozens of separate vendor pages.
Drop-in alternatives for PIC18F4439-I/PT — 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 PIC18F4439-I/PT (same form factor and footprint) — differing in Package, ADC, Operating Temperature, Program Memory (Flash), I/O Pins.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PIC18F4439-E/PT
✅ Drop-In ⚠️ Specs Unverified✓ In Stock
$2.7 / Unit
View Datasheet →PIC18F4431-I/PT
✅ Drop-In✓ In Stock
$4.79 / Unit
View Datasheet →PIC18F4439-I/PT Maximum Ratings & Electrical Characteristics
| Core Architecture | PIC18 8-bit RISC |
| Maximum CPU Clock | 40 MHz |
| Program Memory (Flash) | 12 KB (6K x 16) |
| RAM | 640 bytes |
| EEPROM | 256 bytes |
| Supply Voltage (VDD) | 4.2 V to 5.5 V |
| User I/O Pins | 36 |
| ADC | 10-bit, 8 channels |
| PWM Outputs | 2 dedicated motor-control PWM channels |
| Motor Control Kernel | Yes (single-phase induction motor control focus) |
| Self-Programming | Yes (Flash) |
| In-Circuit Debug (ICD) | Yes |
| Operating Temperature | -40 C to +85 C (Industrial, 'I' suffix) |
| Package | TQFP-44 (PT), 10x10 mm, surface mount |
| Mounting Type | Surface Mount, gull-wing |
| RoHS | Compliant |
PIC18F4439-I/PT Pin Configuration
| Pin 1 | RC0/T1OSO/T1CKI — I/O port C bit 0 / Timer1 oscillator output / Timer1 clock input |
| Pin 2 | RC1/T1OSI/CCP2 — I/O port C bit 1 / Timer1 oscillator input / CCP2 input/output |
| Pin 3 | RC2/CCP1 — I/O port C bit 2 / CCP1 PWM output |
| Pin 4 | RC3/SCK/SCL — I/O port C bit 3 / SPI SCK / I2C SCL |
| Pin 5 | RC4/SDI/SDA — I/O port C bit 4 / SPI data in / I2C data |
| Pin 6 | RC5/SDO — I/O port C bit 5 / SPI data out |
| Pin 7 | RC6/TX/CK — I/O port C bit 6 / USART TX / clock |
| Pin 8 | RC7/RX/DT — I/O port C bit 7 / USART RX / data |
| Pin 9 | OSC1/CLKI/RA7 — Oscillator crystal input / external clock in / port A bit 7 |
| Pin 10 | OSC2/CLKO/RA6 — Oscillator crystal output / clock out / port A bit 6 |
| Pin 11 | MCLR/VPP/RE3 — Master clear reset / programming voltage / port E bit 3 |
| Pin 12 | VDD — Power supply (4.2 V to 5.5 V) |
| Pin 13 | VSS — Ground reference |
| Pin 14 | RB7/PGD — I/O port B bit 7 / ICD programming data |
| Pin 15 | RB6/PGC — I/O port B bit 6 / ICD programming clock |
| Pin 16 | RB5 — I/O port B bit 5 |
| Pin 17 | RB4 — I/O port B bit 4 |
| Pin 18 | RB3/CCP2 — I/O port B bit 3 / CCP2 channel |
| Pin 19 | RB2/PWM1 — I/O port B bit 2 / Motor-control PWM output 1 |
| Pin 20 | RB1/PWM2 — I/O port B bit 1 / Motor-control PWM output 2 |
| Pin 21 | RB0/INT0 — I/O port B bit 0 / external interrupt 0 |
| Pin 22 | VDD — Power supply (4.2 V to 5.5 V) |
| Pin 23 | VSS — Ground reference |
| Pin 24 | RA0/AN0 — I/O port A bit 0 / ADC analog input 0 |
| Pin 25 | RA1/AN1 — I/O port A bit 1 / ADC analog input 1 |
| Pin 26 | RA2/AN2/VREF- — I/O port A bit 2 / ADC analog input 2 / VREF- |
| Pin 27 | RA3/AN3/VREF+ — I/O port A bit 3 / ADC analog input 3 / VREF+ |
| Pin 28 | RA4/AN4/T0CKI — I/O port A bit 4 / ADC analog input 4 / Timer0 clock in |
| Pin 29 | RA5/AN5/SS — I/O port A bit 5 / ADC analog input 5 / SPI slave select |
| Pin 30 | RE0/AN6 — I/O port E bit 0 / ADC analog input 6 |
| Pin 31 | RE1/AN7 — I/O port E bit 1 / ADC analog input 7 |
| Pin 32 | RE2/CS — I/O port E bit 2 / chip select |
| Pin 33 | RD0 — I/O port D bit 0 |
| Pin 34 | RD1 — I/O port D bit 1 |
| Pin 35 | RD2 — I/O port D bit 2 |
| Pin 36 | RD3 — I/O port D bit 3 |
| Pin 37 | RD4 — I/O port D bit 4 |
| Pin 38 | RD5 — I/O port D bit 5 |
| Pin 39 | RD6 — I/O port D bit 6 |
| Pin 40 | RD7 — I/O port D bit 7 |
| Pin 41 | AVDD — Analog supply (4.2 V to 5.5 V) |
| Pin 42 | AVSS — Analog ground reference |
| Pin 43 | NC — Not connected (per datasheet) |
| Pin 44 | NC — Not connected (per datasheet) |
Typical Applications
PIC18F4439-I/PT is suitable for 6 applications: Single-Phase Induction Motor Drive, Appliance Fan / Pump Controller, Switched-Mode Power Supply (SMPS) Controller, Variable-Frequency Drive (VFD) Modem Stage, HVAC Damper and Damper Actuator, Industrial Automation Remote I/O Module.
Single-Phase Induction Motor Drive
The PIC18F4439-I/PT is the silicon that Microchip designed for single-phase induction motor control, so this is its native application. Its integrated motor-control PWM kernel with dedicated time-base and edge/center-aligned modes produces the variable-frequency switching demanded by V/Hz torque profiles, while the 8-channel 10-bit ADC samples shunt-current and back-EMF feedback inside the firmware interrupt. The 12 KB Flash and 640 bytes of RAM are sized for state-machine commutation, PI loop, and small diagnostic UIs. Place 100 nF ceramic bypass caps adjacent to each VDD/VSS pair and keep high-current switching traces away from AVSS/AVDD traces to avoid ADC crosstalk.
Recommended
Appliance Fan / Pump Controller
Ceiling fans, refrigerator compressors, and small circulation pumps run directly from the PIC18F4439-I/PT thanks to its industrial temperature grade and 36 user I/O lines. The 40 MHz PIC18 core provides enough MIPS to handle closed-loop RPM regulation via the input-capture module and quadrature-encoder interface, while the hardware PWM drives TRIAC or IGBT stages with deterministic dead-band control. With low BOM count - MCU, gate driver, and a handful of passives - the design fits behind the wall plate. Self-programming Flash enables in-field firmware updates for fan curves and energy-saving modes.
Recommended
Switched-Mode Power Supply (SMPS) Controller
The PIC18F4439-I/PT's high-speed 10-bit ADC and motor-control PWM kernel translate naturally into digital SMPS control where the firmware actively regulates output voltage and current with peak-current-mode or average-current-mode techniques. The 40 MHz core delivers 10 MIPS, allowing control loops at typical 50-200 kHz switching frequencies when compiled efficiently with the C18 or XC8 toolchain. Brown-out reset and the 4.2 V minimum supply keep the regulator alive during AC input dropouts, while 256 bytes of EEPROM store trim and calibration constants. Isolation is maintained with the MCP2120 UART-to-optical interface.
Recommended
Variable-Frequency Drive (VFD) Modem Stage
Use the PIC18F4439-I/PT as the auxiliary control stage for small variable-frequency drives that need precise PWM and quadrature feedback. The microcontroller's dedicated quadrature encoder interface delivers reliable rotor-position tracking when paired with incremental encoders, while the 36 I/O pins can drive indicator LEDs, fault relays, and a CAN/RS-485 interface. The industrial temperature range matches factory-floor environments with elevated ambient. Add the MCP2561 CAN transceiver for networking and the MCP1700 LDO to derive clean 3.3 V for any host MCUs in the system.
Recommended
HVAC Damper and Damper Actuator
Heating, ventilation, and air-conditioning damper actuators are a strong fit for the PIC18F4439-I/PT because they need precision PWM and encoder feedback in a small, sealed enclosure. The 10-bit ADC measures absolute position through a rotary potentiometer and drives a brushed DC motor through an H-bridge, while the 12 KB Flash accommodates slow diagnostic loops and Modbus-style network slaves. Long-term parameter storage uses the on-chip EEPROM, so trim values survive power cycles. Industrial-grade temperature and in-circuit debug simplify qualification.
Recommended
Industrial Automation Remote I/O Module
The PIC18F4439-I/PT is also used as the supervisory microcontroller in industrial remote I/O modules that fan-out digital inputs and relay outputs over RS-485 or CANopen. Its 36 I/O pins can drive up to 36 external channels in groups multiplexed through the MCP23S17, while the 10-bit ADC reads 4-20 mA analog process signals through op-amp level shifters. The ICD port supports in-circuit debug during commissioning, and self-programming Flash allows field firmware upgrades through Modbus bootloader routines. A watchdog timer and brown-out reset keep the module latched in safe state during industrial transients.
Recommended
Recommended Products Summary
Engineering reference data for PIC18F4439-I/PT — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC18F4439-E/PT | PIC18F4431-I/PT | PIC18F4331-I/PT |
|---|---|---|---|---|
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Package | TQFP-44 (PT) | TQFP-44 (PT) - same | TQFP-44 (PT) - same | TQFP-44 (PT) - same |
| CPU Clock | 40 MHz | 40 MHz | 40 MHz | 40 MHz |
| Program Flash | 12 KB | 12 KB | 16 KB | 8 KB |
| RAM | 640 bytes | 640 bytes | 768 bytes | 256 bytes |
| EEPROM | 256 bytes | 256 bytes | 256 bytes | 256 bytes |
| Operating Temperature | -40 C to +85 C | -40 C to +125 C | -40 C to +85 C | -40 C to +85 C |
| Motor-Control PWM Kernel | Yes (single-phase focus) | Yes (single-phase focus) | Yes (general-purpose family) | Yes (motor-control focus) |
| ADC Channels | 8 channels, 10-bit | 8 channels, 10-bit | 9 channels, 10-bit | 9 channels, 10-bit |
| Supply 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 |
Key Differentiators
- Dedicated single-phase motor-control PWM kernel on-chip (vs PIC18F4431-I/PT)
- Industrial-grade temperature rating included as standard (vs PIC18F4439-E/PT)
- Surface-mount TQFP-44 footprint for compact appliance designs (vs PIC18F4439-I/P (40-pin PDIP))
Design Notes
Place a 100 nF ceramic bypass capacitor next to each VDD/VSS pin pair and a single 10 uF or greater bulk tantalum or ceramic cap on the supply rail. For motor-control layouts where high-current traces can return through the analog ground, split AVSS and VSS only at one point and use a star ground tying the two together near the regulator. The PIC18F4439-I/PT operates from 4.2 V to 5.5 V; supply spikes above absolute maximum 7.5 V on VDD will permanently damage the part.
On the TQFP-44 layout, route the analog AVSS/AVDD pair through a ferrite bead to the digital rail so that high-frequency motor-switching noise cannot couple into ADC samples. Keep the OSC1/OSC2 traces short (under 10 mm) and surrounded by a ground guard ring if the board will operate in high EMI environments. If using a high-speed crystal, place the load caps symmetrically and provide a ground pour under the crystal to suppress coupling. These measures will keep ADC reference noise below 1 LSB at full 40 MHz operation.
Do not operate the PIC18F4439-I/PT above 5.5 V; an external 5 V LDO such as MCP1702 from a 12-24 V bus is preferred over raw 5 V regulators in appliance designs. When using the In-Circuit Debugger port (RB6/RB7), configure the application firmware to release the PGC/PGD pins immediately or debug-from-reset will not connect. Finally, the 12 KB Flash is divided into self-programming and application regions per CONFIG settings - leave at least 128 bytes of buffer or self-programming will fail with BOR.
Compliance Information
Industrial -40 C to +85 C operating range. RoHS and REACH compliant per Microchip product declarations.
