PIC18F4220-I/ML - 8-Bit 40MHz MCU, 4KB Flash, 44-QFN | Microchip
MPN: PIC18F4220-I/ML ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $6.1 | $6.10 |
| 10 | $5.62 | $56.20 |
| 100 | $4.95 | $495.00 |
| 500 | $4.42 | $2,210.00 |
| 1,000 | $3.97 | $3,970.00 |
PIC18F4220-I/ML Overview
A microcontroller (MCU) is a single-chip computer that integrates a CPU core, program and data memory, and programmable I/O peripherals into one package, allowing engineers to replace discrete logic and analog front-ends with deterministic firmware. Within the PIC18F family hierarchy (PIC18F -> 8-bit PIC -> Microchip 8-bit MCU -> microcontroller -> semiconductor), the PIC18F4220 sits in the mid-density "F4220/F4320" group targeted at cost-sensitive designs that still demand enhanced flash and 10-bit ADC integration. Microchip's nanoWatt technology platform provides active and sleep power management modes that reduce quiescent current to microamp levels, making the PIC18F4220-I/ML attractive for line-powered industrial and battery-tolerant sensor interface boards where MCU run-time directly affects system energy budget.
Key feature highlights include 36 programmable digital I/O lines supporting TTL/CMOS inputs and selectable pull-ups, an enhanced flash memory cell rated for at least 100,000 erase/write cycles, and on-chip self-programming support that enables in-application firmware updates without external programmers. The 10-bit ADC delivers a typical conversion time adequate for sub-1 ksps multi-channel scanning, and the dual analog comparators can be configured with an internal reference for autonomous threshold detection without CPU intervention. The MSSP peripheral simplifies integration of SPI/I2C sensors, while the two CCP modules support PWM motor control, IR carrier generation, or capture-based timing measurement. An ICD-friendly architecture is exposed for MPLAB ICD development tools, removing the need for a separate debug header in prototypes.
Architecturally, the PIC18F4220 uses a Harvard RISC core with separate 16-bit instruction and 8-bit data paths, paired with a deterministic instruction pipeline that supports single-cycle 8x8 hardware multiply. The C compiler-friendly instruction set and orthogonal addressing model allow compact code generation, and the device supports MPLAB C18/XC8 development with optimized library footprints for ADC, PWM, and MSSP routines. Power management is handled by selectable oscillator modes (internal RC plus external crystal/HS) and deep sleep states with peripheral-disable registers.
Typical applications include sensor and transducer signal conditioning, industrial control panels, low-cost motor drives (small DC fans, steppers, solenoids), home appliance user interfaces, automotive body controllers (non-AEC-Q100), and battery-charging front-ends. Designers appreciate the wide operating voltage and robust peripheral mix as a foundation for migrating older PIC16 designs to a higher-performance 8-bit platform without retraining on a new toolchain. When integrating the PIC18F4220-I/ML, allocate at least 1 square inch of PCB copper directly under the QFN exposed pad to keep junction temperature within the -40C to +125C operating envelope at full CPU utilization; this is a power-supplied connector-like role where thermal and decoupling discipline determines system stability. This page consolidates distributor pricing, drop-in alternatives, and applied engineering guidance beyond what the manufacturer datasheet alone provides.
Drop-in alternatives for PIC18F4220-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 PIC18F4220-I/ML (same form factor and footprint) — differing in Operating Temperature, Package, Core Architecture, ADC, CCP Modules.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PIC18F4320-I/ML
✅ Drop-In📋 Reference alternative (not in catalog)
PIC18F4220-E/ML
✅ Drop-In✓ In Stock
$4.62 / Unit
View Datasheet →PIC18F4220-I/ML Maximum Ratings & Electrical Characteristics
| Core Architecture | PIC18F, 8-bit RISC |
| Program Memory | 4 KB Flash (2K x 16 words) |
| Data Memory (SRAM) | 512 bytes |
| EEPROM | 256 bytes |
| Maximum CPU Frequency | 40 MHz |
| ADC | 10-bit, 13 channels |
| Analog Comparators | 2 |
| CCP/PWM Modules | 2 |
| I/O Pins | 36 |
| Serial Peripherals | 1x MSSP (SPI / I2C) |
| Operating Temperature | -40C to +85C (Industrial -I grade) |
| Package | 44-QFN (8x8 mm) with exposed pad (ML) |
| Mounting Type | Surface Mount |
| RoHS Status | Compliant |
| Lead-Free / Halogen-Free | Yes |
PIC18F4220-I/ML Pin Configuration
| Pin 1 | RA0/AN0 — PORTA bit 0 / analog channel 0 |
| Pin 2 | RA1/AN1 — PORTA bit 1 / analog channel 1 |
| Pin 3 | RA2/AN2/VREF- — PORTA bit 2 / analog channel 2 / ADC VREF- |
| Pin 4 | RA3/AN3/VREF+ — PORTA bit 3 / analog channel 3 / ADC VREF+ |
| Pin 5 | RA4/T0CKI — PORTA bit 4 / Timer0 clock input |
| Pin 6 | RA5/AN4 — PORTA bit 5 / analog channel 4 |
| Pin 7 | RE0/RD — PORTE bit 0 / parallel-port read |
| Pin 8 | RE1/WR — PORTE bit 1 / parallel-port write |
| Pin 9 | RE2/CS — PORTE bit 2 / parallel-port chip-select |
| Pin 10 | VDD — Digital supply (5V) |
| Pin 11 | VSS — Digital ground reference |
| Pin 12 | OSC1/CLKI/RA7 — Crystal input / external clock / RA7 |
| Pin 13 | OSC2/CLKO/RA6 — Crystal output / clock out / RA6 |
| Pin 14 | RC0/T1OSO/T1CKI — PORTC bit 0 / Timer1 oscillator output or external clock |
| Pin 15 | RC1/T1OSI — PORTC bit 1 / Timer1 oscillator input |
| Pin 16 | RC2/CCP1 — PORTC bit 2 / Capture-Compare-PWM 1 output |
| Pin 17 | RC3/SCK/SCL — PORTC bit 3 / SPI clock / I2C clock |
| Pin 18 | RC4/SDI/SDA — PORTC bit 4 / SPI data-in / I2C data |
| Pin 19 | RC5/SDO — PORTC bit 5 / SPI data-out |
| Pin 20 | RC6/TX/CK — PORTC bit 6 / EUSART transmit or clock |
| Pin 21 | RC7/RX/DT — PORTC bit 7 / EUSART receive or data |
| Pin 22 | RB0/INT0 — PORTB bit 0 / external interrupt 0 |
| Pin 23 | RB1/INT1 — PORTB bit 1 / external interrupt 1 |
| Pin 24 | RB2/INT2 — PORTB bit 2 / external interrupt 2 |
| Pin 25 | RB3/CCP2 — PORTB bit 3 / Capture-Compare-PWM 2 output |
| Pin 26 | RB4 — PORTB bit 4 with interrupt-on-change |
| Pin 27 | RB5 — PORTB bit 5 with interrupt-on-change |
| Pin 28 | RB6/PGC — PORTB bit 6 / in-circuit debugger clock (ICSP) |
| Pin 29 | RB7/PGD — PORTB bit 7 / in-circuit debugger data (ICSP) |
| Pin 30 | MCLR/VPP/RE3 — Master clear reset (active low) / programming voltage / RE3 |
| Pin 31 | VSS — Digital ground reference |
| Pin 32 | VDD — Digital supply (5V) |
| Pin 33 | RD0/PSP0 — PORTD bit 0 / parallel slave port bit 0 |
| Pin 34 | RD1/PSP1 — PORTD bit 1 / parallel slave port bit 1 |
| Pin 35 | RD2/PSP2 — PORTD bit 2 / parallel slave port bit 2 |
| Pin 36 | RD3/PSP3 — PORTD bit 3 / parallel slave port bit 3 |
| Pin 37 | RD4/PSP4 — PORTD bit 4 / parallel slave port bit 4 |
| Pin 38 | RD5/PSP5 — PORTD bit 5 / parallel slave port bit 5 |
| Pin 39 | RD6/PSP6 — PORTD bit 6 / parallel slave port bit 6 |
| Pin 40 | RD7/PSP7 — PORTD bit 7 / parallel slave port bit 7 |
| Pin 41 | AVDD — Analog supply (5V) |
| Pin 42 | AVSS — Analog ground reference |
| Pin 43 | AN5/RA5/SS — Analog channel 5 / RA5 second function / SPI slave select |
| Pin 44 | NC — No connection (pin reserved on 44-QFN variant) |
Typical Applications
PIC18F4220-I/ML is suitable for 6 applications: Industrial Sensor Interface Board, Small DC Motor and Solenoid Control, Home Appliance User Interface and Display Hub, Automotive Body and Interior Module (Non-AEC-Q100), Battery-Operated Data Logger, Educational Development and Prototyping Platform.
Industrial Sensor Interface Board
The PIC18F4220-I/ML is well-suited for industrial sensor interfaces because it provides 13 channels of 10-bit ADC operating from a single +5V supply with selectable references, allowing direct reading of thermocouples, RTDs, strain gauges, or 4-20 mA loop signals through external op-amp signal conditioning. The integrated dual analog comparators can trigger autonomous threshold alerts (e.g., over-temperature or over-pressure events) without CPU overhead, freeing the 40 MHz CPU for filtering, linearization, and serial forwarding. Placed as the central MCU in a PLC analog-input card, the device's 36 I/O pins permit direct drive of DIN-rail status LEDs, optocoupler-isolated digital outputs, and a front-panel LCD interface. The 4 KB Flash holds typical multi-point linearization firmware with headroom; the 512-byte SRAM is sufficient for moving-average or Kalman-style filtering of 1-2 ksps sample streams. Operating environment: -40C to +85C industrial grade, nanoWatt sleep modes reduce quiescent draw to single-digit microamps for line-distributed nodes.
Recommended
Small DC Motor and Solenoid Control
The PIC18F4220-I/ML drives small DC motors and solenoids efficiently by using its two Capture/Compare/PWM modules to generate 10-bit PWM at frequencies up to 40 kHz, providing precise duty-cycle control of brushed DC motors, fans, and proportional solenoid valves. The 36 I/O pins, including 5V-tolerant drive capability on many ports, permit direct MOSFET/IGBT gate drive through 10-100 k gate resistors, and the comparator peripherals can implement hardware overcurrent detection via shunt resistor sense paths. In a 24V solar-tracker or small e-bike controller, the PIC18F4220's CCP outputs gate an H-bridge while AN0-AN3 read thermistor feedback and AN4-AN6 monitor battery voltage. The MSSP peripheral doubles as an SPI interface to a higher-priority drive IC. Power dissipation stays modest because the 5V supply keeps the MCU below 100 mA active, simplifying thermal layout, and the -40C to +85C operating envelope tolerates under-hood and outdoor enclosures.
Recommended
Home Appliance User Interface and Display Hub
In home appliances (washing machines, dishwashers, ovens, coffee makers), the PIC18F4220-I/ML serves as the front-panel control hub, driving multiplexed 7-segment LCD/LED displays and keypad matrices through its 36 digital I/O pins. Its 10-bit ADC has 13 channels, enabling multiple temperature sensor inputs (NTC thermistors for motor, water, and heater), pressure transducers, and rotation sensor taps without external multiplexer ICs. The MSSP can be routed to I2C for a real-time clock, EEPROM, or external OLED display module, keeping the BOM compact. Running at 20-40 MHz with nanoWatt sleep modes, average current consumption in standby stays below 50 uA, which is critical for meeting Energy Star standby budgets. The 4 KB Flash accommodates state-machine firmware plus sensor linearization tables, and Microchip's XC8 C compiler library provides tested drivers for segmented LCD peripherals, keypads, and serial bootloaders. The 44-QFN (8x8 mm, ML) package fits the slim enclosures of modern appliance front-panels.
Recommended
Automotive Body and Interior Module (Non-AEC-Q100)
Although not AEC-Q100 qualified, the PIC18F4220-I/ML is widely used in cabin-grade automotive accessories - door modules, mirror controllers, sunroof drivers, accessory lighting, and HVAC blend-door actuators - where strict AEC-Q100 is unnecessary but industrial-grade temperature tolerance (-40C to +85C) is sufficient. Its 36 I/O pins drive window/liftgate motors, LED strings, and LIN-bus endpoints through an external transceiver like MCP2003, while 13 ADC channels read thermistor feedback, position encoders, and voltage rails. The two CCP modules generate 1 kHz PWM for servo control with resolution high enough for smooth actuator movement. MSSP supports I2C communication with body-controllers and LIN-networked sub-blocks. The 44-QFN (8x8 mm, ML) package enables compact PCB modules that fit inside mirror or door pocket assemblies. For under-hood AEC-Q100 applications, recommend the automotive-grade equivalent family - it shares silicon lineage but is qualified separately.
Recommended
Battery-Operated Data Logger
The PIC18F4220-I/ML makes an excellent core for low-cost battery-operated data loggers thanks to nanoWatt technology sleep modes that reduce quiescent current to microamp levels, drastically extending single-cell battery life. The MCU wakes periodically via watchdog timer, samples a thermistor/MEMS sensor through the 10-bit ADC, writes timestamped values to external EEPROM over I2C, then returns to sleep. Its 4 KB Flash supports a months-long logger firmware with time-stamp averaging and redundant-store algorithms, and 36 I/O leaves headroom for additional digital inputs (PIR sensor, switch state, reed relay). The operating voltage range accommodates 2xAA alkaline through single-cell Li-ion chemistries with the on-chip LDO providing regulated core voltage. Programming is easy via MPLAB ICD, and the PIC18F4220-I/ML maintains production-friendly SoC integration versus discrete design; for smaller logger footprints, the 28-pin PIC18F2220 would be a derivative but does not share the 44-QFN footprint.
Recommended
Educational Development and Prototyping Platform
The PIC18F4220-I/ML is a stable, production-proven device frequently adopted by universities and prototyping labs as a teaching platform for embedded systems due to its comprehensive peripheral mix - 10-bit ADC, MSSP for SPI/I2C, dual CCP, comparators, and 36 I/O pins - in a single, hand-solderable 44-QFN (8x8 mm) or 44-TQFP package. Through-hole variants (40-pin PDIP) exist on the silicon family for solderless breadboards, but the 44-QFN (ML) variant supports training in surface-mount practices and zero-cost breadboard adapter PCBs. Supported by MPLAB X IDE, XC8 C compiler, and a large library of open-source firmware examples, students can implement UART command-line interfaces, PWM motor control, I2C sensor readout, and ADC sampling projects on a single chip. The abundant peripherals also make this part a popular reference design in Microchip's own training material, providing a low-risk option for companies teaching embedded engineering onboarding.
Recommended
Recommended Products Summary
Engineering reference data for PIC18F4220-I/ML — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC18F4320-I/ML | PIC18F4220-E/ML | PIC18F2220-I/ML |
|---|---|---|---|---|
| Brand | Microchip Technology | Microchip Technology (same) | Microchip Technology (same) | Microchip Technology (same) |
| Package | 44-QFN (8x8 mm, ML) | 44-QFN (8x8 mm, ML) - same | 44-QFN (8x8 mm, ML) - same | 28-SOIC (different, only 22 I/O) |
| Program Memory | 4 KB Flash | 8 KB Flash (+100%) | 4 KB Flash (same) | 4 KB Flash (same) |
| Maximum Clock Frequency | 40 MHz | 40 MHz | 40 MHz | 40 MHz |
| ADC | 10-bit, 13 channels | 10-bit, 13 channels | 10-bit, 13 channels | 10-bit, 9 channels (-4) |
| I/O Pins | 36 | 36 | 36 | 22 (-14) |
| Operating Temperature (this product = -I grade) | -40C to +85C | -40C to +85C (same) | -40C to +125C (+40C, E grade) | -40C to +85C (same) |
| CCP/PWM Modules | 2 | 2 | 2 | 2 |
Key Differentiators
- Highest density I/O + ADC combination in 40-MHz PIC18F tier (vs PIC18F2220-I/ML)
- Pin-compatible upgrade path to 8 KB Flash for firmware headroom (vs PIC18F4320-I/ML)
- Industrial temperature grade (-I) with automotive-capable migration option (vs PIC18F4220-E/ML)
- Self-programming Flash supports in-application firmware updates (vs Older PIC16F/18F non-self-programming devices)
- Dual analog comparators with programmable internal reference (vs PIC18F2220 comparators)
Design Notes
The PIC18F4220-I/ML QFN exposed pad must be soldered to a copper pour (recommended: at least 1 square inch / 6.45 cm^2 of 1-oz copper) connected to Vss to keep junction temperature within the -40C to +85C industrial envelope. Estimated: at 40 MHz active operation with all peripherals on, total power dissipation is approximately 100 mW at 5V; without the thermal pad junction-to-ambient thermal resistance exceeds 60 C/W, risking thermal shutdown. Always assign a top-layer continuous plane under the device, stitched with vias to an inner ground plane.
Place Vdd decoupling capacitors (100 nF ceramic + 10 uF bulk tantalum or ceramic) within 5 mm of the Vdd pins (10 and 32 on the 44-QFN package). Add a separate AVdd pin (41) decoupling capacitor of 100 nF dedicated to analog functions, even if both Vdd pins are supplied from the same 5V rail. Sensitive analog inputs (AN0-AN12) should be routed over the AVdd-supplied ground plane (AVss) to prevent digital switching noise from coupling into ADC conversions. Crystal traces (OSC1/OSC2) should be short, symmetric, and ground-guard-ringed. Minimize trace length of high-current drive lines connected to I/O pins to limit EMI emissions.
Three pitfalls frequently appear in PIC18F4220-I/ML designs: (1) Forgetting MCLR pull-up - the MCLR/VPP pin (pin 30) requires a 10-50 kohm pull-up to Vdd for normal operation; in-circuit debug will not initialize without it. (2) Configuring ADC channels not assigned - the PIC18F4220 offers 13 analog channels multiplexed with PORTF/PORTG; make sure AN0-AN12 are configured as analog (ANSELx = 1) before sampling. (3) Reading PORT vs LAT registers - writing to PORT then reading PORT returns the actual pin state, not the latch; for read-modify-write safety, write to LAT and read from PORT only when needed. Additionally, never connect analog signals to a digital PORTB pin with interrupt-on-change enabled without debouncing, because the interrupt generator triggers on every edge. Estimated: assuming 5V supply, 40 MHz CPU, all peripherals enabled, and average programming overhead, total active current is approximately 17 mA at full CPU load (typical from Microchip datasheet DC characteristics).
For the 44-QFN (8x8 mm, ML) package, follow JEDEC-MS-022 Quad Non-Leaded Footprint guidelines: land pads of 0.30 x 0.30 mm centered on a perimeter pattern around an exposed pad of 4.0 x 4.0 mm or larger, with a uniform mask opening on the exposed pad to ensure solder capillary action does not pull the device sideways during reflow. Use NSMD (non-solder-mask defined) land pads for the perimeter pads for best thermal cycling reliability, with ENIG or OSP surface finish. Add corner anchor pins or test points for visual inspection of QFN solder fillet; the small pad size makes insufficient solder invisible from above the package.
Compliance Information
PIC18F4220-I/ML is fully RoHS compliant and halogen-free per Microchip product page. AEC-Q100 status: not qualified - PIC18F4220 family is recommended for industrial and consumer applications, not AEC-Q100 automotive qualification.
