PIC18LF4420-I/ML - 8-Bit MCU, 16KB Flash, 40MHz, 44-QFN | Microchip
MPN: PIC18LF4420-I/ML ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $5.36 | $5.36 |
| 10 | $4.92 | $49.20 |
| 100 | $4.31 | $431.00 |
| 500 | $3.74 | $1,870.00 |
| 1,000 | $3.18 | $3,180.00 |
PIC18LF4420-I/ML Overview
A microcontroller (MCU) is a single-chip computer containing a CPU core, non-volatile program memory (flash), volatile working memory (RAM), and a rich set of on-chip peripherals. Within the embedded hierarchy, an 8-bit MCU like the PIC18F sits below 32-bit Cortex-M parts in arithmetic performance but above discrete logic in functional integration. The PIC18LF4420 belongs to the PIC18F "high-performance 8-bit" family that adds a hardware multiplier, C-friendly architecture, and 16-bit instructions compared to baseline PIC16F parts.
Key features of the PIC18LF4420 include a 10-bit ADC with up to 13 input channels, a 4x4 hardware multiplier for fast DSP-style math, two enhanced CCP modules and one USART, I2C, SPI, and a parallel slave port for external memory expansion. The device supports self-programming under firmware control, allowing bootloader-driven field updates and on-chip EEPROM emulation. An extended watchdog timer and brown-out reset help recover from code faults and brown-out events.
Architecturally, the PIC18LF4420 uses a 16-bit instruction word with an 8-bit data path, a modified Harvard memory map, and a priority-level interrupt controller. The 40 MHz oscillator provides up to 10 MIPS, and the nanoWatt technology reduces sleep current to under 100 nA with the RTCC and watchdog running, which is critical for battery-powered sensors.
Typical applications include industrial sensing and control, USB/HID bridges when paired with a serial interface, low-power sensor hubs, motor control loops, and white-goods user interfaces. The wide voltage range and generous peripheral set make it a popular choice for migration from older PIC16F and PIC18F designs. Drop-in compatibility with PIC18F4520 in the same 44-pin QFN lets engineers move between 5 V F-variant and LF-variant designs without PCB rework.
Drop-in alternatives for PIC18LF4420-I/ML — 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 PIC18LF4420-I/ML (same form factor and footprint) — differing in Package, Timers, ADC, Operating Temperature, Program Memory (Flash).
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PIC18F4520-I/ML
✅ Drop-In📋 Reference alternative (not in catalog)
PIC18LF4520-I/ML
✅ Drop-In✓ In Stock
$4.92 / Unit
View Datasheet →PIC18LF4420-I/PT
✅ Drop-In✓ In Stock
$5.71 / Unit
View Datasheet →PIC18F4420-I/ML
✅ Drop-In📋 Reference alternative (not in catalog)
PIC18LF4320-I/ML
✅ Drop-In📋 Reference alternative (not in catalog)
PIC18LF4420-I/ML Maximum Ratings & Electrical Characteristics
| Series | PIC 18F |
| Core | PIC18 8-bit RISC |
| Program Memory Type | Flash |
| Program Memory Size | 16 KB (8K x 16) |
| RAM Size | 768 bytes |
| EEPROM Size | 256 bytes |
| Maximum Clock Speed | 40 MHz |
| Supply Voltage Range | 2.0 V to 5.5 V |
| I/O Pins | 36 |
| ADC | 10-bit, up to 13 channels |
| Communication Interfaces | UART, I2C, SPI, PSP |
| Timers | 4 x 8/16-bit |
| CCP Modules | 2 Enhanced CCP |
| Operating Temperature | -40 C to +85 C |
| Package | 44-QFN (8x8 mm) with exposed pad |
| Mounting Type | Surface Mount |
| RoHS Status | Compliant |
PIC18LF4420-I/ML Pin Configuration
| Pin 1 | MCLR — Master Clear (Reset) input, active low |
| Pin 2 | OSC1 — Crystal oscillator input or external clock input |
| Pin 3 | OSC2 — Crystal oscillator output |
| Pin 4 | RA0/AN0 — PORTA bit 0 / Analog input AN0 |
| Pin 5 | RA1/AN1 — PORTA bit 1 / Analog input AN1 |
| Pin 6 | RA2/AN2/VREF- — PORTA bit 2 / Analog input AN2 / Negative reference |
| Pin 7 | RA3/AN3/VREF+ — PORTA bit 3 / Analog input AN3 / Positive reference |
| Pin 8 | RA4 — PORTA bit 4 |
| Pin 9 | RA5 — PORTA bit 5 |
| Pin 10 | RA6 — PORTA bit 6 |
| Pin 11 | RA7 — PORTA bit 7 |
| Pin 12 | RB0 — PORTB bit 0 |
| Pin 13 | RB1 — PORTB bit 1 |
| Pin 14 | RB2 — PORTB bit 2 |
| Pin 15 | RB3 — PORTB bit 3 |
| Pin 16 | RB4 — PORTB bit 4 |
| Pin 17 | RB5 — PORTB bit 5 |
| Pin 18 | RB6 — PORTB bit 6 / ICSP clock |
| Pin 19 | RB7 — PORTB bit 7 / ICSP data |
| Pin 20 | VSS — Ground reference |
| Pin 21 | VDD — Positive supply |
| Pin 22 | RC0 — PORTC bit 0 |
| Pin 23 | RC1 — PORTC bit 1 |
| Pin 24 | RC2 — PORTC bit 2 |
| Pin 25 | RC3 — PORTC bit 3 |
| Pin 26 | RC4 — PORTC bit 4 |
| Pin 27 | RC5 — PORTC bit 5 |
| Pin 28 | RC6 — PORTC bit 6 / TX |
| Pin 29 | RC7 — PORTC bit 7 / RX |
| Pin 30 | RE0 — PORTE bit 0 |
| Pin 31 | RE1 — PORTE bit 1 |
| Pin 32 | RE2 — PORTE bit 2 |
| Pin 33 | RD0 — PORTD bit 0 |
| Pin 34 | RD1 — PORTD bit 1 |
| Pin 35 | RD2 — PORTD bit 2 |
| Pin 36 | RD3 — PORTD bit 3 |
| Pin 37 | RD4 — PORTD bit 4 |
| Pin 38 | RD5 — PORTD bit 5 |
| Pin 39 | RD6 — PORTD bit 6 |
| Pin 40 | RD7 — PORTD bit 7 |
| Pin 41 | VSS — Ground reference |
| Pin 42 | VDD — Positive supply |
| Pin 43 | NC — Not connected |
| Pin 44 | NC — Not connected |
Typical Applications
PIC18LF4420-I/ML is suitable for 6 applications: Industrial Sensor Hub, White Goods User Interface, Battery-Powered Wireless Sensor Node, Automotive Body Controller (Sub-System), Educational and Hobby Electronics, Motor Control and PWM Driver.
Industrial Sensor Hub
The PIC18LF4420-I/ML's 36 digital I/O lines and 10-bit ADC with up to 13 input channels let a single chip scan an entire array of analog and digital sensors. Its wide 2.0 V to 5.5 V supply accepts 3.3 V and 5 V transducer signals directly, while the nanoWatt sleep mode drops below 100 nA for battery or energy-harvested sensors. A UART plus SPI pair allows the MCU to bridge sensor data upstream to a host controller or industrial gateway. The 256-byte EEPROM provides a small non-volatile calibration store, and the 16 KB flash is enough for a real-time scheduler plus a Modbus RTU slave.
Recommended
White Goods User Interface
A washing machine or dishwasher front panel needs to drive multiple LED indicators, scan a matrix keypad, and time motor or pump events. The PIC18LF4420-I/ML exposes 36 I/O pins and four timer/counter blocks, enough for the keypad scan plus PWM-driven indicator dimming. The 40 MHz clock keeps debounce and motor-tach math responsive, while the wide voltage range lets the board share the 3.3 V rail with the LCD driver. Its -40 C to +85 C industrial range covers under-cabinet heat, and the 256-byte EEPROM stores end-user cycle settings across power cycles.
Recommended
Battery-Powered Wireless Sensor Node
Wireless sensor nodes spend most of their life asleep and wake briefly to take a measurement and transmit. The PIC18LF4420-I/ML's nanoWatt sleep current under 100 nA with the RTCC and watchdog running makes it ideal for coin-cell or two-AAA powered designs. The 16 KB flash fits a small RTOS-style scheduler plus a vendor-specific RF protocol stack; UART or SPI can drive a low-power 2.4 GHz or sub-GHz transceiver. The 2.0 V minimum supply allows the cell to discharge all the way down to its end-of-life voltage without regulator intervention.
Recommended
Automotive Body Controller (Sub-System)
While the PIC18LF4420-I/ML is not AEC-Q100 qualified, it is commonly used inside cabin sub-modules and development prototypes where 12 V is regulated to 5 V or 3.3 V. Its 36 I/O lines can drive mirror adjusters, seat switches, and lighting logic; the enhanced CCP modules generate the PWM needed for dimming interior LEDs. The wide voltage range tolerates load-dump transients after the regulator, and the 16 KB flash fits a simple CAN- or LIN-over-UART slave. Migrating to PIC18F4520-I/ML or AEC-Q100 qualified K-series is straightforward when production grade is needed.
Recommended
Educational and Hobby Electronics
The PIC18LF4420-I/ML is widely supported by Microchip's MPLAB X IDE, the free XC8 C compiler, and a large library of community code examples, making it ideal for teaching microcontroller fundamentals. The 44-pin QFN exposes enough I/O for full sensor and actuator projects, while the on-chip debug circuitry lets students step through code on real hardware. Its 5.5 V tolerance allows direct 5 V hobby modules (servo, motor) to be wired without level shifters. Hobbyists can prototype on the PIC18LF4520-I/ML or migrate to the 28-pin PIC18LF2420-I/SP family later.
Recommended
Motor Control and PWM Driver
The PIC18LF4420-I/ML's two enhanced CCP modules and four timers can drive up to four PWM channels for brushed DC or stepper motor control. Its 40 MHz core provides the computational headroom for field-oriented control loops at modest RPM. The 10-bit ADC samples current shunt or back-EMF signals, while UART reports telemetry to a higher-level controller. The 256-byte EEPROM stores calibrated motor parameters across power cycles, and the wide voltage range supports both 3.3 V logic-level and 5 V H-bridge designs.
Recommended
Recommended Products Summary
Engineering reference data for PIC18LF4420-I/ML — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC18F4520-I/ML | PIC18LF4520-I/ML | PIC18LF4420-I/PT | PIC18F4420-I/ML | PIC18LF4320-I/ML |
|---|---|---|---|---|---|---|
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Package | 44-QFN (8x8 mm) | 44-QFN (8x8 mm) - same | 44-QFN (8x8 mm) - same | 44-TQFP - same pinout | 44-QFN (8x8 mm) - same | 44-QFN (8x8 mm) - same |
| Program Memory (Flash) | 16 KB | 32 KB | 32 KB | 16 KB | 16 KB | 8 KB |
| RAM | 768 bytes | 1536 bytes | 1536 bytes | 768 bytes | 768 bytes | 256 bytes |
| Supply Voltage | 2.0 V to 5.5 V | 4.2 V to 5.5 V | 2.0 V to 5.5 V | 2.0 V to 5.5 V | 4.2 V to 5.5 V | 2.0 V to 5.5 V |
| Maximum Clock Speed | 40 MHz | 40 MHz | 40 MHz | 40 MHz | 40 MHz | 40 MHz |
| I/O Pins | 36 | 36 | 36 | 36 | 36 | 36 |
| ADC Channels | 13 (10-bit) | 13 (10-bit) | 13 (10-bit) | 13 (10-bit) | 13 (10-bit) | 13 (10-bit) |
| Operating Temperature | -40 C to +85 C | -40 C to +85 C | -40 C to +85 C | -40 C to +85 C | -40 C to +85 C | -40 C to +85 C |
Key Differentiators
- Wide 2.0 V to 5.5 V operating voltage, lower than 5 V-only F-variant (vs PIC18F4420-I/ML)
- Smaller flash than the LF4520 but identical pinout (vs PIC18LF4520-I/ML)
- Highest pin-count surface-mount variant in the family (vs PIC18LF4420-I/PT)
Design Notes
The PIC18LF4420-I/ML operates across 2.0 V to 5.5 V; for designs that must reject 12 V load-dump transients, place a series resistor plus a 5.1 V Zener or a small switching regulator ahead of the VDD pin. Decouple VDD with a 100 nF ceramic capacitor placed within 5 mm of the supply pin, and add a bulk 10 uF tantalum or ceramic cap on the same rail. The exposed thermal pad (pin 45) must be soldered to a PCB ground plane for thermal performance and should use multiple vias to a continuous inner copper layer.
Do not confuse the PIC18LF4420 with the PIC18F4420. The LF part supports 2.0 V to 5.5 V, while the F part requires 4.2 V minimum; firmware written for the LF variant will run on the F variant but may fail to program or execute correctly at 3.3 V. The MCLR pin must be pulled high through a 10 kΩ pull-up and decoupled with a 100 nF cap to ground to avoid spurious resets during power-up. The ICSP pins RB6 and RB7 are also PORTB bits and must not be loaded down with low-impedance circuitry during programming.
Place the 40 MHz crystal or resonator within 5 mm of OSC1 and OSC2 with short symmetrical traces and a grounded guard ring to reduce stray capacitance. Keep ADC analog traces (AN0-AN12) away from switching nodes such as PWM or CCP outputs, and route them over a continuous ground plane to minimize coupling. For the 44-QFN, fan out all inner rows to inner PCB layers rather than surface traces to keep the breakout clean; reserve a continuous copper pour under the exposed pad.
Compliance Information
RoHS and REACH compliant per Microchip product page; lead-free ML suffix indicates Pb-free plating. AEC-Q100 not qualified - choose PIC18F66K80-I/PT or other K-series parts for automotive.