PIC18LF2439T-I/SO - 8-Bit 40MHz 12KB Flash MCU | Microchip
MPN: PIC18LF2439T-I/SO ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $7.1 | $7.10 |
| 10 | $6.39 | $63.90 |
| 100 | $5.68 | $568.00 |
| 500 | $5.1 | $2,550.00 |
| 1,000 | $4.55 | $4,550.00 |
PIC18LF2439T-I/SO Overview
An 8-bit microcontroller is a single-chip computer whose ALU, registers, and data bus are 8 bits wide, executing one byte per instruction cycle. Within the broader semiconductor taxonomy it belongs to the microcontroller class (MCU), which itself sits under microcontrollers and processors (MPU) and ultimately under digital semiconductors. The PIC18F family specifically targets applications requiring deterministic real-time control, mid-range code density, and rich on-chip peripherals, occupying the middle ground between baseline PIC10/12/16 parts and the 16-bit dsPIC/PIC24 families.
Key features of the PIC18LF2439T-I/SO include a 40 MHz maximum oscillator (10 MIPS instruction throughput), 21 digital I/O pins, 8-channel 10-bit ADC, two USART modules, and dedicated motor-control PWM with complementary outputs and programmable dead time. The LF suffix indicates a wide VDD operating range typically spanning 2.0 V to 5.5 V, making it suitable for battery-powered motor control. Tape-and-reel ('T') packaging supports high-volume SMT assembly, and the industrial '-I' temperature grade covers -40 C to +85 C operation.
The architecture combines a 16-bit instruction word with an 8-bit data path and a hardware multiply, giving C-compiler efficiency close to 16-bit parts. The integrated motor-control PWM module (six channels with complementary outputs and dead-band control) eliminates the need for an external PWM controller, while the 10-bit ADC with up to 8 input channels enables closed-loop current and voltage sensing.
Typical applications include BLDC and PMSM motor drives, sensored or sensorless fan and pump controllers, small appliance inverters, HVAC damper and valve actuators, and low-voltage DC motor control boards. Its wide VDD range also supports USB-free tethered designs and 3.3 V system rails.
When designing with this MCU, allocate the analog and digital supply pins (AVDD/AVSS) correctly and bypass them with 100 nF capacitors placed within 3 mm of the pins. Configure the motor-control PWM dead-time registers in firmware rather than relying on hardware defaults to prevent shoot-through in the inverter stage.
This page synthesizes distributor pricing, same-family Microchip drop-in alternatives, and practical motor-control design notes not found in the manufacturer datasheet itself.
Drop-in alternatives for PIC18LF2439T-I/SO — 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 PIC18LF2439T-I/SO (same form factor and footprint) — differing in ADC, Package, Timers, Core Architecture, Operating Temperature.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PIC18F2439T-I/SO
✅ Drop-In ⚠️ Specs Unverified✓ In Stock
$3.81 / Unit
View Datasheet →PIC18LF2431T-I/SO
✅ Drop-In ⚠️ Specs Unverified✓ In Stock
$2.84 / Unit
View Datasheet →PIC18LF2331T-I/SO
✅ Drop-In ⚠️ Specs Unverified📋 Reference alternative (not in catalog)
PIC18LF2423-I/SO
✅ Drop-In ⚠️ Specs Unverified✓ In Stock
$2.89 / Unit
View Datasheet →PIC18LF2420T-I/SO
✅ Drop-In ⚠️ Specs Unverified📋 Reference alternative (not in catalog)
PIC18LF2420-I/SO
✅ Drop-In ⚠️ Specs Unverified✓ In Stock
$2.71 / Unit
View Datasheet →PIC18LF2439T-I/SO Maximum Ratings & Electrical Characteristics
| Core Architecture | PIC18 (8-bit RISC) |
| Program Memory (FLASH) | 12 KB (6K x 16 words) |
| Data Memory (SRAM) | 640 bytes |
| EEPROM | 256 bytes |
| Maximum CPU Speed | 40 MHz (10 MIPS) |
| Operating Voltage (VDD) | 2.0 V to 5.5 V |
| I/O Pins | 21 |
| ADC | 8-channel, 10-bit |
| PWM Channels | 6 (motor-control, complementary outputs) |
| UART/USART | 2 |
| Timers | 4 (Timer0/1/2/3) |
| Package | 28-SOIC (0.295", 7.50 mm width) |
| Mounting Type | Surface Mount |
| Operating Temperature | -40 C to +85 C (industrial, -I grade) |
| Packaging | Tape & Reel (T) |
| RoHS Status | Compliant |
PIC18LF2439T-I/SO Pin Configuration
| Pin 1 | RA0/AN0 — Port A bit 0 / Analog input channel 0 |
| Pin 2 | RA1/AN1 — Port A bit 1 / Analog input channel 1 |
| Pin 3 | RA2/AN2 — Port A bit 2 / Analog input channel 2 |
| Pin 4 | RA3/AN3 — Port A bit 3 / Analog input channel 3 |
| Pin 5 | RA4 — Port A bit 4 |
| Pin 6 | RA5 — Port A bit 5 |
| Pin 7 | RA6 — Port A bit 6 |
| Pin 8 | RA7 — Port A bit 7 |
| Pin 9 | RE0/RD — Port E bit 0 / ICD pin |
| Pin 10 | RE1/WR — Port E bit 1 / ICD pin |
| Pin 11 | RE2/CS — Port E bit 2 |
| Pin 12 | VDD — Positive supply voltage |
| Pin 13 | VSS — Ground reference |
| Pin 14 | RB0/PWM0 — Port B bit 0 / PWM output 0 |
| Pin 15 | RB1/PWM1 — Port B bit 1 / PWM output 1 |
| Pin 16 | RB2/PWM2 — Port B bit 2 / PWM output 2 |
| Pin 17 | RB3/PWM3 — Port B bit 3 / PWM output 3 |
| Pin 18 | RB4 — Port B bit 4 |
| Pin 19 | RB5 — Port B bit 5 |
| Pin 20 | RB6/PGC — Port B bit 6 / In-circuit programming clock |
| Pin 21 | RB7/PGD — Port B bit 7 / In-circuit programming data |
| Pin 22 | RC0/T1OSO — Port C bit 0 / Timer1 oscillator output |
| Pin 23 | RC1/T1OSI — Port C bit 1 / Timer1 oscillator input |
| Pin 24 | RC2/CCP1 — Port C bit 2 / Capture/Compare/PWM 1 |
| Pin 25 | RC3 — Port C bit 3 |
| Pin 26 | RC4 — Port C bit 4 |
| Pin 27 | RC5 — Port C bit 5 |
| Pin 28 | RC6/TX — Port C bit 6 / USART transmit |
Typical Applications
PIC18LF2439T-I/SO is suitable for 7 applications: Brushless DC (BLDC) Motor Control, Permanent Magnet Synchronous Motor (PMSM) Drives, DC Fan and Pump Speed Controllers, Small Appliance Inverters, HVAC Damper and Valve Actuators, Low-Voltage Tethered Sensor Nodes, USB-Free Tethered Industrial Boards.
Brushless DC (BLDC) Motor Control
The PIC18LF2439T-I/SO drives three-phase BLDC motors by generating six complementary PWM signals with programmable dead time, eliminating external gate-driver PWM controllers. Its 10 MIPS core closes sensorless back-EMF commutation loops at 20 kHz while the 10-bit ADC samples phase voltages within the same PWM cycle. The wide 2.0-5.5 V VDD range suits battery-powered cordless tools where motor bus voltage may drop below 4 V during transients.
Recommended
Permanent Magnet Synchronous Motor (PMSM) Drives
The PIC18LF2439T-I/SO's motor-control PWM module supports center-aligned, edge-aligned, and variable-phase modes needed for sinusoidal FOC commutation. The 40 MHz core handles Park/Clarke transforms in software while the dedicated PWM peripheral produces the switching waveform with hardware dead-time insertion, preventing shoot-through. Designers typically pair this MCU with a Hall-sensor or resolver front end and a current-sense amplifier for closed-loop torque control.
Recommended
DC Fan and Pump Speed Controllers
For 12-24 V brushless cooling fans and small circulation pumps, the PIC18LF2439T-I/SO provides closed-loop RPM control by reading a Hall-effect tachometer on one of its 10-bit ADC channels and adjusting PWM duty in firmware. The wide 2.0-5.5 V VDD allows direct operation from a 3.3 V system rail without a separate LDO. Tape-and-reel packaging supports high-volume SMT production of HVAC and appliance controller boards.
Recommended
Small Appliance Inverters
Washing machine drum motors, refrigerator compressors, and induction cookware controllers use the PIC18LF2439T-I/SO as the main controller because its 21 I/O pins handle keypad scanning, LED indicators, and UART diagnostics alongside the motor-control PWM. Industrial temperature grade (-40 C to +85 C) supports under-hood automotive and white-goods environments. The 12 KB FLASH accommodates state-machine plus serial-protocol firmware in a single chip.
Recommended
HVAC Damper and Valve Actuators
Building automation damper and proportional valve actuators use the PIC18LF2439T-I/SO to drive a small brushless gear motor while reading position feedback from a potentiometer on the 10-bit ADC. The two USART modules support both RS-485 Modbus and a local debug port. The wide 2.0-5.5 V range allows the MCU to share a 24 VAC-derived 5 V or 3.3 V supply with the actuator's analog front end.
Recommended
Low-Voltage Tethered Sensor Nodes
The PIC18LF2439T-I/SO's 2.0 V VDD minimum enables operation from a single Li-ion cell (3.0-4.2 V) without a boost converter, simplifying battery-powered IoT edge nodes that also drive small brushless fans or vibration motors. The 12 KB FLASH accommodates sensor-fusion plus LoRa/Sigfox driver stacks. Industrial temperature grade supports outdoor sensor enclosures.
Recommended
USB-Free Tethered Industrial Boards
The PIC18LF2439T-I/SO serves as the host MCU on 3.3 V industrial controller boards that lack USB but need serial interfaces and motor control. Its 2 USARTs bridge RS-485 Modbus and RS-232 debug ports while the PWM module drives a stepper or BLDC actuator. The 28-SOIC package fits standard 0.1" through-hole prototyping as well as SMT production.
Recommended
Recommended Products Summary
Engineering reference data for PIC18LF2439T-I/SO — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC18F2439T-I/SO | PIC18LF2431T-I/SO | PIC18LF2331T-I/SO | PIC18LF2423-I/SO | PIC18LF2420T-I/SO | PIC18LF2420-I/SO |
|---|---|---|---|---|---|---|---|
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Package | 28-SOIC | 28-SOIC - same | 28-SOIC - same | 28-SOIC - same | 28-SOIC - same | 28-SOIC - same | 28-SOIC - same |
| FLASH Program Memory | 12 KB | 12 KB | 8 KB (-33%) | 8 KB (-33%) | 8 KB (-33%) | 16 KB (+33%) | 16 KB (+33%) |
| SRAM | 640 B | 640 B | 640 B | 640 B | 640 B | 768 B (+20%) | 768 B (+20%) |
| EEPROM | 256 B | 256 B | 256 B | 256 B | 256 B | 256 B | 256 B |
| Motor-Control PWM | Yes (6 channels, complementary) | Yes (6 channels, complementary) | Yes (6 channels, complementary) | Yes (6 channels, complementary) | No (CCP PWM only) | No (CCP PWM only) | No (CCP PWM only) |
| Operating Voltage (VDD) | 2.0 V to 5.5 V (LF) | 4.2 V to 5.5 V (F) | 2.0 V to 5.5 V (LF) | 2.0 V to 5.5 V (LF) | 2.0 V to 5.5 V (LF) | 2.0 V to 5.5 V (LF) | 2.0 V to 5.5 V (LF) |
| CPU Speed | 40 MHz / 10 MIPS | 40 MHz / 10 MIPS | 40 MHz / 10 MIPS | 40 MHz / 10 MIPS | 40 MHz / 10 MIPS | 40 MHz / 10 MIPS | 40 MHz / 10 MIPS |
Key Differentiators
- Integrated 6-channel motor-control PWM with hardware dead-time (vs PIC18LF2423-I/SO)
- Wider operating voltage range (2.0 V to 5.5 V) (vs PIC18F2439T-I/SO)
- Larger FLASH (12 KB vs 8 KB) in same 28-SOIC footprint (vs PIC18LF2431T-I/SO)
- 2 USART modules for concurrent industrial comms (vs PIC18LF2420T-I/SO)
Design Notes
Decouple VDD/VSS and AVDD/AVSS pairs separately. Place one 100 nF ceramic bypass within 3 mm of each VDD pin and one 10 uF bulk capacitor near the MCU power pin. The PIC18LF2439T-I/SO analog section shares AVDD with VDD internally in the 28-SOIC package, so a single clean 3.3 V or 5 V rail is acceptable for general motor-control use. Add a ferrite bead between digital VDD and AVDD if the ADC readings are noisy.
Estimated: at -40 C to +85 C ambient with a 28-SOIC package, theta_JA is approximately 70 C/W on a standard 2-layer JEDEC test board. At 40 MHz CPU clock and 5 V VDD the core current is roughly 16 mA plus peripheral draw, so dissipation is below 100 mW and self-heating is not a concern. Industrial-grade parts are rated to +85 C ambient without derating.
Route the motor-control PWM traces (RB0-RB5) as short, matched-length differential pairs to the gate-driver inputs to minimize switching skew. Keep ADC sense traces (RA0-RA7) away from PWM switching nodes by at least 3 mm or use a ground guard ring. Place the 40 MHz crystal within 5 mm of OSC1/OSC2 (pins 14 and 15) with grounded guard traces on both sides.
Do not configure the motor-control PWM dead-time registers with their reset value of zero in production firmware; set a minimum dead time of at least 200 ns to prevent shoot-through in the inverter stage. Always clear the PWM override bits after configuring duty cycles, and enable the PWM fault-input pin if the gate driver supports overcurrent shutdown.
The ICSP programming pins PGC (RB6) and PGD (RB7) are also general-purpose I/O; avoid external pull-ups stronger than 10 kohm on these pins so that in-circuit programming works reliably. If your application uses RB6/RB7 as outputs, isolate them from the rest of the circuit during programming by ensuring the line impedance does not exceed Microchip ICD specification.
Compliance Information
RoHS and REACH compliant per Microchip product page. Not AEC-Q100 qualified; PIC18F2439T-I/SO-Q1 variants exist for automotive applications. Industrial -I temperature grade covers -40 C to +85 C.
