PIC18LF4331T-I/PT - 40MHz 8-bit MCU 8KB FLASH 44-TQFP | Microchip
MPN: PIC18LF4331T-I/PT ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $7.12 | $7.12 |
| 10 | $6.4 | $64.00 |
| 100 | $5.35 | $535.00 |
| 500 | $4.75 | $2,375.00 |
| 1,000 | $4.2 | $4,200.00 |
PIC18LF4331T-I/PT Overview
What is an 8-bit microcontroller? An 8-bit microcontroller (MCU) is a single-chip computer that processes data in 8-bit-wide chunks, integrates CPU core, program memory (FLASH/ROM), data memory (RAM), and a rich peripheral set including timers, ADC, PWM, and communication interfaces. Positioned in the taxonomy: 8-bit microcontroller -> microcontroller -> embedded processor -> semiconductor device. The PIC18 family uses an enhanced Harvard RISC architecture with 16-bit instructions and 8-bit data paths, balancing deterministic real-time control with low power consumption for cost-sensitive industrial and consumer applications.
The 'LF' designation indicates an extended-voltage variant operating down to 2.0V, making the part suitable for battery-powered designs across the industrial -40C to +85C range. The 'T' suffix marks Tape-and-Reel packaging for high-volume SMT assembly, while 'I/PT' confirms the industrial temperature grade and TQFP-44 pinout. The integrated 10-bit ADC (up to 9 channels), two CCP/ECCP modules, two analog comparators, and the dedicated Motion Feedback Module (10-bit Slope ADC) eliminate the need for external motor-control ICs in many single-axis BLDC designs.
Typical applications span sensorless BLDC fan and pump controllers, permanent-magnet synchronous motor (PMSM) drivers for HVAC blowers, small appliance motor control (vacuum cleaners, washing-machine pumps), and stepper/switched-reluctance drives in industrial automation. Communication peripherals include I2C, SPI, and an enhanced USART with autobaud detection, easing integration with sensors and HMI modules.
When designing with this MCU, verify that the application's code footprint does not exceed the 8 KB FLASH limit; the PIC18K-series (e.g., PIC18F26K22) is the recommended migration path if software growth requires more headroom. Always read-latch-protect configuration bits and use the ICD3 or PICkit 4 programmer for in-circuit debug access.
This page consolidates distributor stock, parametric same-package alternatives, and application-level design notes that complement the datasheet block diagrams for production engineers evaluating 44-pin TQFP motor-control MCUs.
Drop-in alternatives for PIC18LF4331T-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 PIC18LF4331T-I/PT (same form factor and footprint) — differing in Package, Mounting Type, RAM, Communication Interfaces, I/O Pins.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PIC18LF4331-I/PT
✅ Drop-In📋 Reference alternative (not in catalog)
PIC18F4331-I/PT
✅ Drop-In✓ In Stock
$3.05 / Unit
View Datasheet →PIC18F4331T-I/PT
✅ Drop-In📋 Reference alternative (not in catalog)
PIC18LF4431-I/PT
✅ Drop-In✓ In Stock
$5.45 / Unit
View Datasheet →PIC18LF4431T-I/PT
✅ Drop-In📋 Reference alternative (not in catalog)
PIC18LF4331T-I/PT Maximum Ratings & Electrical Characteristics
| Series | PIC18F (PIC18LF4331) |
| Core Architecture | 8-bit PIC18 RISC (Enhanced Harvard) |
| Core Size | 8-bit |
| Maximum CPU Speed | 40 MHz |
| Program Memory (FLASH) | 8 KB (4K x 16 words) |
| RAM | 768 bytes |
| I/O Pins | 34 |
| Package | 44-TQFP (10x10 mm), suffix /PT |
| Mounting Type | Surface Mount, Tape & Reel (T suffix) |
| Supply Voltage Range | 2.0 V to 5.5 V (LF extended-voltage family) |
| Operating Temperature | -40C to +85C (industrial, 'I') |
| ADC | 10-bit, up to 9 channels |
| PWM Module | Power Control PWM (PCPWM), 14-bit resolution, 6 outputs |
| Communication Interfaces | I2C, SPI, Enhanced USART (with autobaud) |
| Timers | TMR0/TMR1/TMR2/TMR3 + Motion Feedback Module (10-bit Slope ADC) |
| Comparators | 2 analog comparators |
| CCP/ECCP Modules | 2 (1 standard CCP + 1 ECCP) |
| MSL Level | MSL3 (per JEDEC J-STD-020, TQFP-44) |
| RoHS Status | Compliant |
PIC18LF4331T-I/PT 44-tqfp (10x10 mm), suffix /pt Pin Configuration Guide
Pin configuration for PIC18LF4331T-I/PT (44-tqfp (10x10 mm), suffix /pt package). This digital IC includes GPIO, communication interfaces (UART, SPI, I2C), and power pins. Refer to the manufacturer datasheet for alternate pin functions and configuration options. Essential for embedded system design and PCB layout.
No detailed pinout data available for PIC18LF4331T-I/PT.
Refer to the datasheet for full pin configuration.
Typical Applications
PIC18LF4331T-I/PT is suitable for 6 applications: Sensorless BLDC Motor Controller, PMSM Drive for HVAC Blowers, Industrial Pump and Fan VFDs, Small Appliance Motor Control, Switched-Reluctance Motor (SRM) Drive, Industrial Automation Sensor Node.
Sensorless BLDC Motor Controller
The PIC18LF4331T-I/PT is purpose-built for sensorless BLDC motor control: its 14-bit-resolution Power Control PWM module generates 3-phase complementary outputs with programmable dead-time (80 ns resolution), while the 10-bit Motion Feedback Module (Slope ADC) directly samples BEMF voltages from the floating phase without external op-amps. Operating voltage of 2.0V-5.5V supports both 3.3V and 5V supply rails typical of small fans and pumps.
Recommended
PMSM Drive for HVAC Blowers
Permanent-magnet synchronous motor (PMSM) drive designs in HVAC blowers benefit from the PIC18LF4331T-I/PT's integrated 6 PWM outputs and 9-channel ADC. The 40 MHz core sustains field-oriented control loops with a 20 kHz PWM carrier while leaving CPU bandwidth for airflow regulation. The LF 2.0V-5.5V range simplifies integration with 24V-to-5V bias designs, and the -40C to +85C industrial rating covers outdoor unit temperature stress.
Recommended
Industrial Pump and Fan VFDs
Variable-frequency drives for industrial pumps and fans up to 1 HP leverage the PIC18LF4331T-I/PT's Power Control PWM for V/Hz or field-oriented control. The 768-byte SRAM is sufficient for the PI controllers and lookup tables of these moderate-speed drives; 8 KB FLASH comfortably hosts reference firmware such as the Microchip AN1078 sensorless BLDC and AN1160 PFC reference designs. Internal 10-bit ADC and 2 comparators eliminate external signal conditioning.
Recommended
Small Appliance Motor Control
Washing-machine pumps, dishwasher circulation pumps, vacuum-cleaner BLDC motors, and refrigerator compressor controllers leverage the PIC18LF4331T-I/PT's single-chip integration. The 34 I/O pins directly drive H-bridges and triac commutation circuits, while I2C/SPI expand into EEPROM storage and user-interface buttons. The LF supply range allows operation directly from a rectified 3.3V rail, reducing BOM cost in mass-market consumer appliances.
Recommended
Switched-Reluctance Motor (SRM) Drive
Switched-reluctance motor drives use the PIC18LF4331T-I/PT's precise PWM timing to commutate each phase independently. The 10-bit Motion Feedback Module samples the incremental encoder or resolver position feedback, and the high-speed ADC triggers torque-ripple reduction control loops at every 100 us rotor-position event. Industrial -40C to +85C rating supports unenclosed industrial motor housings.
Recommended
Industrial Automation Sensor Node
Beyond motor control, the PIC18LF4331T-I/PT fits industrial sensor nodes that require local actuation and deterministic serial communication. Its Enhanced USART with autobaud detection directly interfaces RS-485 transceivers for Modbus RTU master/slave nodes, while the I2C bus links to EEPROM, RTCs, and 4-20 mA loop ADCs. The industrial -40C to +85C temperature range and low 1 uA sleep current enable battery-backed remote installations.
Recommended
Recommended Products Summary
Engineering reference data for PIC18LF4331T-I/PT — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC18LF4331-I/PT | PIC18F4331-I/PT | PIC18F4331T-I/PT | PIC18LF4431-I/PT | PIC18LF4431T-I/PT |
|---|---|---|---|---|---|---|
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Package | 44-TQFP (10x10 mm) | 44-TQFP (10x10 mm) - same | 44-TQFP (10x10 mm) - same | 44-TQFP (10x10 mm) - same | 44-TQFP (10x10 mm) - same | 44-TQFP (10x10 mm) - same |
| Supply Voltage | 2.0V to 5.5V (LF) | 2.0V to 5.5V (LF) | 4.2V to 5.5V (F only) | 4.2V to 5.5V (F only) | 2.0V to 5.5V (LF) | 2.0V to 5.5V (LF) |
| Max CPU Speed | 40 MHz | 40 MHz | 40 MHz | 40 MHz | 40 MHz | 40 MHz |
| Program FLASH | 8 KB | 8 KB | 8 KB | 8 KB | 8 KB | 8 KB |
| RAM | 768 bytes | 768 bytes | 768 bytes | 768 bytes | 768 bytes | 768 bytes |
| I/O Pins | 34 | 34 | 34 | 34 | 36 | 36 |
| PWM Channels | 6 Power Control PWM | 6 Power Control PWM | 6 Power Control PWM | 6 Power Control PWM | 8 Power Control PWM | 8 Power Control PWM |
| ADC Channels | 9 (10-bit) | 9 (10-bit) | 9 (10-bit) | 9 (10-bit) | 13 (10-bit) | 13 (10-bit) |
| Packaging Format | Tape & Reel (T) | Tray | Tray | Tape & Reel | Tray | Tape & Reel |
| Lifecycle | Active | Active | Active | Active | Active | Active |
Key Differentiators
- Low-voltage LF supply range supports 3.3V battery-powered designs (vs PIC18F4331-I/PT)
- Integrated 14-bit Power Control PWM with motion feedback module (vs PIC18F45K40-I/PT)
- Extended motor-control I/O at the same 44-TQFP footprint (vs PIC18LF4431T-I/PT)
- 8 KB FLASH vs 64 KB in newer PIC18F26K22 - migration headroom (vs PIC18F4331T-I/PT (5V-only))
Design Notes
Estimated: at 5V VDD and 40 MHz CPU clock with all peripherals disabled, PIC18LF4331T-I/PT core current is approximately 11 mA per Microchip datasheet; at 3.3V VDD the same workload drops to ~6 mA. Decouple VDD with a 100 nF ceramic capacitor placed within 5 mm of the TQFP-44 pin 14, plus a bulk 4.7-10 uF tantalum or polymer cap on each VDD/VSS pair. The on-chip LDO requires a 10 uF reservoir cap on VDDCORE for FLASH programming stability.
The 44-TQFP (10x10 mm) package has a theta_JA of approximately 70 C/W on a 2-layer PCB with no thermal vias. Continuous operation at full 40 MHz across 5V VDD produces a worst-case ~1.5W internal dissipation in motor-control loops - on enclosed motor housings, route top-side copper pours under the exposed paddle region and stitch 6-8 thermal vias to inner ground planes to keep junction below 100C.
TQFP-44 land pattern requires 0.8 mm pitch pads (IPC-7351 nominal). Use NSMD (non-solder-mask-defined) pads on outer-layer footprints for consistent stencil aperture alignment; 6 mil stencil thickness for 0.8 mm pitch devices prevents solder-bridging between adjacent pins. Route ADC input traces (RA0-RA5, RE0-RE2) as far from PWM and oscillator nets as possible to avoid coupling into the 10-bit ADC.
Always program the configuration register bits via ICSP before connecting any I/O load - unconfigured MCLR can lock the part in reset. The Power Control PWM outputs (RC1, RC2, RE0-RE4) require explicit PPS selection for advanced routing. Avoid using RC7/RC6 with the internal oscillator only if the ICSP pins will be used in production; reserve them for in-circuit debug.
Compliance Information
RoHS and REACH compliant per Microchip product environmental compliance documents. Lead-free finish confirmed for /PT TQFP lead-pitch. AEC-Q100 not applicable - PIC18LF4331 family targets industrial motor control, not automotive. Halogen-free status not stated in publicly available datasheet, set to unknown per Data Authenticity Rule 2.
