PIC18LF4520-I/PT - 8-Bit 40MHz 32KB Flash MCU 44-TQFP | Microchip
MPN: PIC18LF4520-I/PT ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $7.92 | $7.92 |
| 10 | $7.13 | $71.30 |
| 100 | $6.32 | $632.00 |
| 500 | $5.74 | $2,870.00 |
| 1,000 | $5.21 | $5,210.00 |
PIC18LF4520-I/PT Overview
Key features include 36 digital I/O pins, a 10-bit analog-to-digital converter with up to 13 input channels, four timer modules, two capture/compare/PWM modules, two USART modules, one MSSP (SPI/I2C) peripheral, and a nanoWatt power-managed sleep architecture. The wide 2.0V to 5.5V supply range accommodates both 3.3V and 5V rails, while the LF silicon process variant delivers lower core current draw than the standard F parts at equivalent clock speeds.
The PIC18 architecture provides a C-friendly 16-bit instruction word with 8-bit data path, 31-level hardware stack, and interrupt-priority support. The integrated 32 KB self-programmable flash supports In-Circuit Serial Programming (ICSP) and In-Circuit Debugging (ICD), enabling field firmware updates and free MPLAB X IDE development with no toolchain cost. The 256-byte EEPROM and 1536-byte SRAM are sufficient for small embedded datalogging and protocol-handling tasks.
Typical applications include industrial sensor interfacing, low-power motor control, USB-to-UART bridges, small-format motor drives, building automation nodes, and consumer appliance control boards. The LF variant's nanoWatt technology is particularly advantageous for battery-powered instruments where sleep-mode current in the microampere range extends operating life.
When designing with this device, ensure decoupling on VDD/VSS pins (one 100 nF per supply pin plus a bulk 10 uF), route the ICSP/ICD pins (PGC/PGD) to a programming header for firmware updates, and check the MCLR pull-up network for reliable reset behaviour. For high-EMI environments, add a small series resistor on MCLR and place the crystal within 10 mm of the OSC pins.
Drop-in alternatives for PIC18LF4520-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 PIC18LF4520-I/PT (same form factor and footprint) — differing in Package, Timers, ADC, Core, Data RAM.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PIC18F4520-I/PT
✅ Drop-In📋 Reference alternative (not in catalog)
PIC18LF4423-I/PT
✅ Drop-In✓ In Stock
$3.58 / Unit
View Datasheet →PIC18LF4520-I/PT Maximum Ratings & Electrical Characteristics
| Core | PIC18 (8-bit enhanced RISC) |
| Program Memory (Flash) | 32 KB |
| RAM | 1536 bytes |
| EEPROM | 256 bytes |
| Maximum CPU Speed | 40 MHz (10 MIPS) |
| Supply Voltage (VDD) | 2.0 V to 5.5 V |
| I/O Pins | 36 |
| ADC | 10-bit, up to 13 channels |
| Timers | 4 |
| CCP Modules | 2 |
| USART | 2 |
| MSSP (SPI/I2C) | 1 |
| Operating Temperature | -40C to +85C (Industrial) |
| Package | 44-pin TQFP (10x10 mm, PT) |
| Mounting Type | Surface Mount |
| RoHS Status | Compliant |
| MSL Level | 3 |
PIC18LF4520-I/PT Pin Configuration
| Pin 1 | MCLR/VPP/RE3 — Master Clear reset input or programming voltage; RE3 digital input only |
| Pin 2 | RA0/AN0 — PORTA bit 0; analog input 0 |
| Pin 3 | RA1/AN1 — PORTA bit 1; analog input 1 |
| Pin 4 | RA2/AN2/VREF- — PORTA bit 2; analog input 2; ADC negative reference |
| Pin 5 | RA3/AN3/VREF+ — PORTA bit 3; analog input 3; ADC positive reference |
| Pin 6 | RA4/T0CKI — PORTA bit 4; Timer0 clock input |
| Pin 7 | RA5/AN4 — PORTA bit 5; analog input 4 |
| Pin 8 | RA6/OSC2/CLKO — PORTA bit 6; oscillator output; clock output |
| Pin 9 | RA7/OSC1/CLKI — PORTA bit 7; oscillator input; clock input |
| Pin 10 | VSS — Ground reference |
| Pin 11 | VDD — Positive supply voltage (2.0-5.5 V) |
| Pin 12 | RB0/INT0/AN12 — PORTB bit 0; external interrupt 0; analog input 12 |
| Pin 13 | RB1/INT1/AN10 — PORTB bit 1; external interrupt 1; analog input 10 |
| Pin 14 | RB2/INT2/AN8 — PORTB bit 2; external interrupt 2; analog input 8 |
| Pin 15 | RB3/INT3/AN9 — PORTB bit 3; external interrupt 3; analog input 9 |
| Pin 16 | RB4/AN11 — PORTB bit 4; analog input 11 |
| Pin 17 | RB5/PGM — PORTB bit 5; low-voltage ICSP enable |
| Pin 18 | RB6/PGC — PORTB bit 6; ICSP clock |
| Pin 19 | RB7/PGD — PORTB bit 7; ICSP data |
| Pin 20 | VSS — Ground reference |
| Pin 21 | VDD — Positive supply voltage (2.0-5.5 V) |
| Pin 22 | RC0/T1OSO/T1CKI — PORTC bit 0; Timer1 oscillator output or clock input |
| Pin 23 | RC1/T1OSI/CCP2 — PORTC bit 1; Timer1 oscillator input; CCP2 PWM output |
| Pin 24 | RC2/CCP1 — PORTC bit 2; CCP1 PWM output |
| Pin 25 | RC3/SCK/SCL — PORTC bit 3; SPI clock or I2C clock |
| Pin 26 | RC4/SDI/SDA — PORTC bit 4; SPI data in or I2C data |
| Pin 27 | RC5/SDO — PORTC bit 5; SPI data out |
| Pin 28 | RC6/TX/CK — PORTC bit 6; USART async transmit or sync clock |
| Pin 29 | RC7/RX/DT — PORTC bit 7; USART async receive or sync data |
| Pin 30 | VSS — Ground reference |
| Pin 31 | VDD — Positive supply voltage (2.0-5.5 V) |
| Pin 32 | RD0/PSP0 — PORTD bit 0; parallel slave port data 0 |
| Pin 33 | RD1/PSP1 — PORTD bit 1; parallel slave port data 1 |
| Pin 34 | RD2/PSP2 — PORTD bit 2; parallel slave port data 2 |
| Pin 35 | RD3/PSP3 — PORTD bit 3; parallel slave port data 3 |
| Pin 36 | RD4/PSP4 — PORTD bit 4; parallel slave port data 4 |
| Pin 37 | RD5/PSP5 — PORTD bit 5; parallel slave port data 5 |
| Pin 38 | RD6/PSP6 — PORTD bit 6; parallel slave port data 6 |
| Pin 39 | RD7/PSP7 — PORTD bit 7; parallel slave port data 7 |
| Pin 40 | VSS — Ground reference |
| Pin 41 | VDD — Positive supply voltage (2.0-5.5 V) |
| Pin 42 | RE0/RD/AN5 — PORTE bit 0; read control or analog input 5 |
| Pin 43 | RE1/WR/AN6 — PORTE bit 1; write control or analog input 6 |
| Pin 44 | RE2/CS/AN7 — PORTE bit 2; chip select or analog input 7 |
Typical Applications
PIC18LF4520-I/PT is suitable for 6 applications: Industrial Sensor Conditioning, Battery-Powered Data Logger, HVAC Control Board, Small Motor Drive Controller, Consumer Appliance Control, Educational / Hobby Development Board.
Industrial Sensor Conditioning
The PIC18LF4520-I/PT fits industrial sensor-conditioning boards where its 10-bit 13-channel ADC, 2.0-5.5 V supply range, and 36 GPIO lines provide ample headroom for multi-signal conditioning. Its nanoWatt sleep modes and 40 MHz MIPS throughput let a single MCU read thermocouples, pressure sensors, and digital inputs while still servicing the two USARTs for fieldbus (Modbus RTU, RS-485) traffic. The LF silicon runs directly from a 3.3 V regulated rail or a 2-cell Li-ion pack without a boost converter.
Recommended
Battery-Powered Data Logger
The PIC18LF4520-I/PT is a strong fit for portable data loggers thanks to its LF silicon process and nanoWatt technology, which drop core current draw well below 1 mA in Sleep mode while still supporting 2.0 V operation from nearly-depleted batteries. The 32 KB flash stores the logging firmware, 256 bytes of EEPROM holds calibration constants, and 1536 bytes of SRAM acts as the rolling sample buffer. Real-time clock discipline and SD card write cycles are managed by the MSSP SPI channel, while the 10-bit ADC digitizes sensor inputs at programmable rates.
Recommended
HVAC Control Board
Commercial and residential HVAC control boards use the PIC18LF4520-I/PT because its 40 MHz core can scan keypads, drive triac-fired outputs via the CCP/PWM modules, and simultaneously maintain a Modbus link to a building-management system. The 13-channel ADC reads return-air temperature, supply-air temperature, humidity sensors, and potentiometer setpoints with sufficient resolution for closed-loop fan/blower control. Wide 2.0-5.5 V operation lets the board ride out power glitches on rectified 24 VAC supplies without resetting.
Recommended
Small Motor Drive Controller
BLDC and stepper drive boards with moderate performance needs use the PIC18LF4520-I/PT as the supervisory controller. Its two CCP modules generate PWM gate-drive signals for the half-bridge drivers, while the 10-bit ADC samples phase currents via shunt amplifiers for basic torque/speed regulation. The 40 MHz core and 10 MIPS throughput execute the commutation table and PI control loop at 20 kHz PWM frequency without CPU saturation, and the wide 2-5.5 V supply keeps the logic rail stable across motor inrush transients.
Recommended
Consumer Appliance Control
Washing machines, dishwashers, and coffee machines integrate the PIC18LF4520-I/PT because its 32 KB flash accommodates the full appliance state machine and its two USARTs interface with the user display board and motor inverter simultaneously. The 256-byte EEPROM stores user preferences and last-cycle state across power cycles, while the nanoWatt Idle mode powers the front panel when the appliance is in standby. The industrial temperature grade ensures reliable operation in kitchen thermal environments up to 85C ambient.
Recommended
Educational / Hobby Development Board
Universities and maker communities use the PIC18LF4520-I/PT on development boards because the free MPLAB X IDE, free XC8 compiler, and inexpensive PICkit programmers provide a complete zero-cost toolchain. The 44-pin TQFP breaks out enough GPIO and peripheral pins to teach timers, ADC, USART, I2C, and SPI exercises in a single chip, while ICSP/ICD lets students single-step through C code on real hardware. The wide 2-5.5 V supply lets the same board run from USB 5 V or a single Li-ion cell, simplifying lab power setups.
Recommended
Recommended Products Summary
Engineering reference data for PIC18LF4520-I/PT — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC18F4520-I/PT | PIC18LF4423-I/PT | PIC18LF4520-I/ML |
|---|---|---|---|---|
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Package | 44-pin TQFP (PT) | 44-pin TQFP (PT) - same | 44-pin TQFP (PT) - same | 44-pin QFN (ML) - DIFFERENT |
| Program Flash | 32 KB | 32 KB | 16 KB | 32 KB |
| RAM | 1536 B | 1536 B | 768 B | 1536 B |
| EEPROM | 256 B | 256 B | 256 B | 256 B |
| Supply Voltage | 2.0-5.5 V | 4.2-5.5 V | 2.0-5.5 V | 2.0-5.5 V |
| Maximum Clock | 40 MHz (10 MIPS) | 40 MHz (10 MIPS) | 40 MHz (10 MIPS) | 40 MHz (10 MIPS) |
| I/O Pins | 36 | 36 | 25 | 36 |
| ADC | 10-bit, 13 channels | 10-bit, 13 channels | 12-bit, 12 channels | 10-bit, 13 channels |
| Operating Temperature | -40C to +85C | -40C to +85C | -40C to +85C | -40C to +85C |
Key Differentiators
- Wide 2.0-5.5 V supply range across the LF silicon (vs PIC18F4520-I/PT)
- Industry-standard 32 KB / 1536 B / 256 B memory profile (vs PIC18LF4423-I/PT)
- TQFP-44 package with 0.8 mm pitch for hand-soldering-friendly prototyping (vs PIC18LF4520-I/ML)
Design Notes
Decoupling is critical on the four VDD/VSS pairs (pins 11/10, 21/20, 31/30, 41/40) of the PIC18LF4520-I/PT 44-pin TQFP. Place one 100 nF X7R ceramic capacitor within 3 mm of each VDD pin, plus a single shared 10 uF X5R bulk capacitor near the chip. For battery-powered designs, add a 10 ohm ferrite bead on the supply rail feeding the analog-sensitive VDD pin (pin 11) to filter switching-noise from the digital pins.
The MCLR pin (pin 1) on the PIC18LF4520-I/PT is RE3-input-only, which means it cannot drive high as a digital output. Do not wire MCLR directly to VDD with a 0 ohm link - always use a 10 kohm pull-up so the ICSP programmer can drive VPP during flash programming. A common mistake is omitting the 100 nF cap on MCLR, which causes spurious resets in noisy motor-drive environments.
Route the ICSP/ICD pins RB6/PGC (pin 18) and RB7/PGD (pin 19) directly to a 5-pin header with no series resistors, and place the header within 50 mm of the MCU for reliable programming. Keep the crystal or resonator within 10 mm of OSC1/OSC2 (pins 9/8) and surround it with a ground pour to minimize EMI pickup. For high-speed ADC sampling, separate the AVdd/VREF analog traces from the digital switching traces and use a star-ground topology at the MCU's VSS pins.
Compliance Information
RoHS and REACH compliance per Microchip product page. Not AEC-Q100 qualified - this is a general-purpose industrial grade part. Lead-free (Pb-free) reflow-compatible per JEDEC J-STD-020.
