PIC18LF45K22-I/ML - 8-Bit 64MHz 32KB Flash XLP MCU | Microchip
MPN: PIC18LF45K22-I/ML ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $3.54 | $3.54 |
| 10 | $3.19 | $31.90 |
| 100 | $2.85 | $285.00 |
| 500 | $2.55 | $1,275.00 |
| 1,000 | $2.28 | $2,280.00 |
PIC18LF45K22-I/ML Overview
A PIC18 microcontroller is an 8-bit Harvard-architecture MCU from Microchip's PIC18 family, positioned between the baseline PIC10/12/16 series and the 16-bit PIC24/dsPIC families. The PIC18 lineage is widely used in consumer, industrial, and automotive-grade applications where deterministic real-time performance, broad peripheral integration, and a long-lived toolchain (MPLAB X, XC8 compiler) are valued. Within the broader taxonomy, PIC18 belongs to Microcontrollers -> Integrated Circuits -> Embedded Semiconductors. The 'LF' prefix designates the low-voltage variant optimized for battery-powered systems, while 'K22' identifies the specific silicon revision with nanoWatt XLP ultra-low-power technology.
Key differentiating features of the PIC18LF45K22-I/ML include 32KB self-write Flash with 100K endurance cycles, nanoWatt XLP sleep current below 100 nA, hardware Peripheral Pin Select (PPS) for flexible signal routing, a 10-bit ADC with up to 28 channels, and dual rail-to-rail comparators with programmable reference. The 8x8 mm 44-pin QFN package reduces board area vs. equivalent 44-pin TQFP parts while maintaining the full peripheral complement.
Technically, the PIC18LF45K22 implements an enhanced 8-bit RISC CPU with a hardware multiply routine, 31-level hardware stack, and a priority interrupt controller. Its internal 16MHz oscillator with 4x PLL reaches 64MHz instruction rate, while nanoWatt XLP mode reduces idle current to ~20 nA typical. The integrated mTouch hardware supports capacitive touch sensing without external components.
Typical applications include battery-powered IoT sensor nodes, low-power motor control, capacitive touch human-machine interfaces, USB device peripherals (with the internal USB-capable variants of the family), industrial control panels, and consumer appliances requiring low standby current. The wide peripheral set also supports LCD drive and metering applications.
When designing with this device, ensure the LF voltage range (1.8V to 3.6V) is observed across all operating modes including programming. Decoupling capacitors should be placed within 5mm of the VDD/VSS pairs, and the QFN exposed pad must be soldered to the PCB ground plane for thermal dissipation and electrical grounding.
This page synthesizes distributor pricing as of 2026-09-29, drop-in alternatives from Microchip's K22 and J-series families, and practical design notes not found on individual distributor listings.
Drop-in alternatives for PIC18LF45K22-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 PIC18LF45K22-I/ML (same form factor and footprint) — differing in ADC, Package, Core Architecture, MSL Level, Program Memory (Flash).
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PIC18F45K22-I/ML
✅ Drop-In✓ In Stock
$2.65 / Unit
View Datasheet →PIC18LF46K22-I/ML
✅ Drop-In✓ In Stock
$4.22 / Unit
View Datasheet →PIC18F46K22-I/ML
✅ Drop-In ⚠️ Specs Unverified📋 Reference alternative (not in catalog)
PIC18LF45K22-E/ML
✅ Drop-In ⚠️ Specs Unverified📋 Reference alternative (not in catalog)
PIC18LF45K42-I/ML
✅ Drop-In✓ In Stock
$2.55 / Unit
View Datasheet →PIC18LF45J50-I/ML
✅ Drop-In ⚠️ Specs Unverified📋 Reference alternative (not in catalog)
PIC18LF45K22-I/ML Maximum Ratings & Electrical Characteristics
| Core | PIC18 8-bit RISC |
| Program Memory (Flash) | 32 KB (16K x 16) |
| Data RAM | 1536 bytes |
| Data EEPROM | 256 bytes |
| Maximum CPU Speed | 64 MHz |
| Operating Voltage Range | 1.8 V to 3.6 V |
| ADC | 10-bit, up to 28 channels |
| Comparators | 2 rail-to-rail analog |
| USART/SPI/I2C | 2 (with Peripheral Pin Select) |
| Timers | 5 (16-bit / 8-bit mix) |
| Capture/Compare/PWM | 3 ECCP + 2 CCP modules |
| Package | 44-pin QFN (8x8 mm) - ML |
| Mounting Type | Surface Mount |
| Operating Temperature | -40 C to +85 C (Industrial) |
| RoHS Status | Compliant |
| Low-Power Technology | nanoWatt XLP |
| Hardware Stack | 31 levels |
PIC18LF45K22-I/ML Pin Configuration
| Pin 1 | RB5 — PORTB bit 5 / I/O |
| Pin 2 | RB4 — PORTB bit 4 / I/O |
| Pin 3 | RB3 — PORTB bit 3 / I/O |
| Pin 4 | RB2 — PORTB bit 2 / I/O |
| Pin 5 | RB1 — PORTB bit 1 / I/O |
| Pin 6 | RB0 — PORTB bit 0 / INT0 |
| Pin 7 | VDD — Positive supply voltage |
| Pin 8 | VSS — Ground reference |
| Pin 9 | RA7 — PORTA bit 7 / OSC1 |
| Pin 10 | RA6 — PORTA bit 6 / OSC2 |
| Pin 11 | RA5 — PORTA bit 5 |
| Pin 12 | RA4 — PORTA bit 4 |
| Pin 13 | RA3 — PORTA bit 3 |
| Pin 14 | RA2 — PORTA bit 2 |
| Pin 15 | RA1 — PORTA bit 1 |
| Pin 16 | RA0 — PORTA bit 0 |
| Pin 17 | RE3 — PORTE bit 3 |
| Pin 18 | RE2 — PORTE bit 2 |
| Pin 19 | RE1 — PORTE bit 1 |
| Pin 20 | RE0 — PORTE bit 0 |
| Pin 21 | VDD — Positive supply voltage |
| Pin 22 | VSS — Ground reference |
| Pin 23 | RD7 — PORTD bit 7 |
| Pin 24 | RD6 — PORTD bit 6 |
| Pin 25 | RD5 — PORTD bit 5 |
| Pin 26 | RD4 — PORTD bit 4 |
| Pin 27 | RC7 — PORTC bit 7 / RX |
| Pin 28 | RC6 — PORTC bit 6 / TX |
| Pin 29 | RC5 — PORTC bit 5 |
| Pin 30 | RC4 — PORTC bit 4 |
| Pin 31 | RC3 — PORTC bit 3 / SCL |
| Pin 32 | RC2 — PORTC bit 2 / SDA |
| Pin 33 | RC1 — PORTC bit 1 |
| Pin 34 | RC0 — PORTC bit 0 |
| Pin 35 | RD3 — PORTD bit 3 |
| Pin 36 | RD2 — PORTD bit 2 |
| Pin 37 | RD1 — PORTD bit 1 |
| Pin 38 | RD0 — PORTD bit 0 |
| Pin 39 | MCLR — Master Clear / Reset input |
| Pin 40 | RB7 — PORTB bit 7 |
| Pin 41 | RB6 — PORTB bit 6 / ICSPCLK |
| Pin 42 | NC — Not connected (per datasheet) |
| Pin 43 | NC — Not connected (per datasheet) |
| Pin 44 | NC — Not connected (per datasheet) |
Typical Applications
PIC18LF45K22-I/ML is suitable for 6 applications: Battery-Powered IoT Sensor Nodes, Capacitive Touch Human-Machine Interface, Low-Power Motor Control (BLDC / Stepper), Industrial Control Panels & Metering, USB Device Peripherals (HID / CDC / Audio), Consumer Appliances (Coffee Machines, Thermostats).
Battery-Powered IoT Sensor Nodes
The PIC18LF45K22-I/ML fits IoT sensor node applications because its 1.8V-3.6V operating range matches 2x AA alkaline or single-cell Li-ion batteries, and nanoWatt XLP sleep current below 100 nA extends battery life to multiple years. The 64 MHz CPU supports protocol stacks (Modbus, MQTT-SN) while the 10-bit ADC with up to 28 channels interfaces directly with environmental sensors (temperature, humidity, gas). Compared to a discrete low-power MCU plus ADC front-end, integrating these functions in one 44-pin QFN chip reduces BOM and PCB area. Designers typically operate the MCU at 8 MHz from the internal oscillator to minimize active current while keeping duty-cycled RF transmissions fast. Recommended companion MPNs for sensor interfaces and external sensors: PIC18LF45K22-E/P, PIC18LF27K40-I/ML, and PIC18LF26K22-I/SO.
Recommended
Capacitive Touch Human-Machine Interface
The PIC18LF45K22-I/ML serves capacitive touch HMIs well because its integrated mTouch module supports up to 28 touch channels without external touch ICs, and the 64 MHz CPU can debounce and process a 16-button panel at sub-10 ms response time. Using the on-chip charge-time measurement unit (CTMU), engineers implement waterproof capacitive sliders and proximity sensors that survive harsh environments. Compared to a discrete capacitive touch controller plus MCU, integrating touch sensing into the host MCU reduces BOM by 50% and simplifies firmware. Industrial design constraints favor the 8x8 mm QFN-44 footprint, which sits behind a glass panel without visible heat dissipation. Recommended companion MPNs for HMIs and user interface: PIC18LF45K22-E/ML, PIC18LF25K42-I/SO, and PIC18LF26K40-I/MV.
Recommended
Low-Power Motor Control (BLDC / Stepper)
The PIC18LF45K22-I/ML handles low-power BLDC and stepper motor control applications because its three ECCP modules generate complementary PWM with programmable dead-time, and the 64 MHz CPU closes current/torque loops within 16 us per cycle. The 28-channel ADC samples back-EMF and current shunt signals at up to 100 ksps aggregate. The 1.8V-3.6V supply supports 3.3V gate-driver interfaces (e.g., MCP8024), and nanoWatt XLP idle modes enable standby current below 1 mA between motion commands. For 24V industrial motor drives, an external DC-DC step-down feeds VDD. Compared to a discrete dsPIC, this PIC18 option costs less but tops out at roughly 60 V/1 A drive stages. Recommended companion MPNs for motor control: PIC18F45K22-I/ML, PIC18LF45K22-E/P, and PIC18LF26K22-E/ML.
Recommended
Industrial Control Panels & Metering
The PIC18LF45K22-I/ML fits industrial metering applications because its 10-bit ADC with differential inputs supports PT100 RTD and shunt-resistor current sensing, and dual comparators enable zero-cross detection for triac-based load switching. The 256 bytes of EEPROM retains calibration and tamper counters during power loss. nanoWatt XLP sleep extends battery-backed utility meter lifetime beyond 10 years. Compared to dedicated metering ICs, the PIC18 approach trades measurement resolution for full programmability, custom communications (Modbus, M-Bus, Wireless M-Bus), and easy firmware upgrades. The 44-pin QFN-44 footprint supports compact panel-mount designs. Recommended companion MPNs for industrial and metering: PIC18LF45J50-I/PT, PIC18LF4523-I/ML, and PIC18LF4580-I/P.
Recommended
USB Device Peripherals (HID / CDC / Audio)
Although the PIC18LF45K22-I/ML itself lacks integrated USB, designers migrate firmware to the pin-compatible PIC18LF45J50-I/ML which adds full-speed USB 2.0 OTG with on-chip transceiver. Both share the same 44-pin QFN footprint, peripheral set, and most register definitions, easing migration. The 32-64 KB Flash and 2 KB RAM support HID, CDC, and basic audio class drivers. Compared to adding an external USB controller (e.g., MCP2221A), integrating USB saves BOM and PCB space. With 3.0V minimum VDD for USB compliance and the LF45J50's 2.0-3.6V range, single-cell Li-ion battery-powered USB peripherals are practical. Recommended companion MPNs for USB peripherals: PIC18LF45J50-I/PT, PIC18LF26J11-I/ML, and PIC18LF25J10-I/ML.
Recommended
Consumer Appliances (Coffee Machines, Thermostats)
The PIC18LF45K22-I/ML serves consumer appliances because the K22 family supports a wide operating voltage, integrated mTouch for capacitive user interfaces, dual comparators for NTC thermistor sensing, and PWM timers for SSR/triac control of heaters and pumps. The 32 KB Flash accommodates state-machine firmware plus diagnostic logging. nanoWatt XLP sleep (sub-100 nA typical) keeps standby power below 0.5 W to meet EU regulations. Compared to discrete logic plus op-amp thermostat designs, a single PIC18 reduces PCB cost while enabling OTA firmware updates via UART bootloader. Recommended companion MPNs for consumer and appliances: PIC18LF25K22-I/SO, PIC18LF26K22-I/SO, and PIC18LF27K42-I/SO.
Recommended
Recommended Products Summary
Engineering reference data for PIC18LF45K22-I/ML — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC18F45K22-I/ML | PIC18LF46K22-I/ML | PIC18F46K22-I/ML | PIC18LF45K22-E/ML | PIC18LF45K42-I/ML |
|---|---|---|---|---|---|---|
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Package | 44-pin QFN (8x8 mm) - ML | 44-pin QFN (8x8 mm) - ML | 44-pin QFN (8x8 mm) - ML | 44-pin QFN (8x8 mm) - ML | 44-pin QFN (8x8 mm) - ML | 44-pin QFN (8x8 mm) - ML |
| Flash Memory | 32 KB | 32 KB | 64 KB | 64 KB | 32 KB | 32 KB |
| RAM | 1536 bytes | 1536 bytes | 3896 bytes | 3896 bytes | 1536 bytes | 2048 bytes |
| Operating Voltage Range | 1.8 V to 3.6 V | 1.8 V to 5.5 V | 1.8 V to 3.6 V | 1.8 V to 5.5 V | 1.8 V to 3.6 V | 1.8 V to 3.6 V |
| Maximum CPU Speed | 64 MHz | 64 MHz | 64 MHz | 64 MHz | 64 MHz | 64 MHz |
| ADC Resolution | 10-bit | 10-bit | 10-bit | 10-bit | 10-bit | 12-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 +125 C | -40 C to +85 C |
Key Differentiators
- Higher Flash headroom with same footprint (vs PIC18F45K22-I/ML)
- 2x Flash upgrade path without PCB redesign (vs PIC18LF46K22-I/ML)
- Integrated USB on pin-compatible variant (vs PIC18LF45J50-I/ML)
Design Notes
Estimated: at 3.3V VDD, 64 MHz CPU, all peripherals active, the PIC18LF45K22-I/ML typically draws ~12 mA; in nanoWatt XLP sleep this drops below 100 nA. For a battery-powered sensor node duty-cycled 0.1% active, average current is dominated by the 16 mA active phase but energy per cycle stays low. The 4x PLL only engages when VDD >= 3.0V - at 1.8V operation, FOSC must remain at 16 MHz or below.
Place a 100 nF decoupling capacitor within 5 mm of every VDD/VSS pair on the 44-pin QFN package; this part has 4 VDD/VSS pairs distributed around the package to reduce loop inductance. The exposed thermal pad (pin 45, EP) must be soldered to a continuous PCB ground plane with at least 9 thermal vias (0.3 mm drill) to dissipate ~1 W. Do not route signal traces under the EP - the solder joint reliability depends on solid thermal and electrical grounding.
Do not exceed 3.6V VDD on the LF variant - this permanently damages the MCU; use PIC18F45K22 for 5V systems. The MCLR pin must have a 10 kohm pull-up to VDD for normal operation; if left floating, the device may randomly reset or fail to start. When using ICSP programming, the PGM/DATA/clock lines must not be loaded by external circuitry that prevents signal levels from reaching the device pins. Configure CONFIG1L for the correct oscillator mode (HS, XT, INTIO) before first programming to avoid lock-out.
Compliance Information
RoHS compliant per Microchip product page. Industrial temperature grade only; the -E/ML variant provides extended temperature but is not AEC-Q100 qualified for automotive.
