PIC18LF45K22-E/P - 32KB Flash XLP 8-bit MCU, 40-PDIP | Microchip
MPN: PIC18LF45K22-E/P ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $4.4 | $4.40 |
| 10 | $3.85 | $38.50 |
| 100 | $3.32 | $332.00 |
| 500 | $2.95 | $1,475.00 |
| 1,000 | $2.62 | $2,620.00 |
PIC18LF45K22-E/P Overview
What is a microcontroller? A microcontroller (MCU) is a single-chip computer that combines a CPU core, non-volatile program memory (Flash), working memory (RAM), data EEPROM, and a rich set of on-chip peripherals (ADC, timers, communication ports, comparators, PWM). PIC18 microcontrollers belong to the 8-bit Harvard-architecture family and sit inside the broader category of embedded microcontrollers -> microcontrollers -> integrated circuits -> semiconductors, and the nanoWatt XLP line represents Microchip's ultra-low-power extension of that family.
Key features of the PIC18LF45K22-E/P include nanoWatt XLP technology for sub-µA sleep currents, two Enhanced USART modules, two MSSP (SPI/I2C) modules, a 10-bit ADC with up to 28 input channels, and up to 36 digital I/O pins. Internal oscillator options (up to 16 MHz) and on-chip voltage reference simplify BOM, while the integrated CTMU (Charge Time Measurement Unit) enables touch and capacitive sensing.
The architecture separates program and data buses (Harvard), features a 16-bit instruction word, and supports hardware multiply and 31-level priority interrupts. With XLP deep-sleep currents as low as 20 nA (typical, per datasheet), the device is engineered for long-battery-life designs and includes nanoWatt XLP sleep and idle modes.
Typical applications include low-power sensor nodes, portable instrumentation, battery-powered medical devices, industrial control panels, USB-CDC peripherals, and educational/development platforms. The 40-pin PDIP package is also preferred for prototyping and hobby applications through-hole assembly is convenient.
A critical design tip: the 'E' suffix denotes the Extended temperature range (-40C to +125C); use the '-I/' variant only for commercial 0C to +85C designs. The PIC18LF45K22-E/P (PDIP) is recommended for new designs and replaces the older PIC18F452 in most 40-pin DIP footprints, although peripheral mapping must be verified.
This page synthesizes distributor pricing, drop-in alternatives, and practical design notes not found in the manufacturer datasheet.
Drop-in alternatives for PIC18LF45K22-E/P — 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-E/P (same form factor and footprint) — differing in Package, Program Memory (Flash), ADC, I/O Pins, Communication.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PIC18LF46K22-E/P
✅ Drop-In✓ In Stock
$3.5 / Unit
View Datasheet →PIC18LF44K22-I/P
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View Datasheet →PIC18LF45K22-E/MV
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View Datasheet →PIC18LF45K42-E/P
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$1.99 / Unit
View Datasheet →PIC18F45K22-E/P
✅ Drop-In✓ In Stock
$2.78 / Unit
View Datasheet →PIC18LF46K22-I/P
✅ Drop-In📋 Reference alternative (not in catalog)
PIC18LF45K22-E/P Maximum Ratings & Electrical Characteristics
| Product Type | 8-bit Microcontroller (MCU) |
| Series | PIC18LF "K22" XLP |
| Core | PIC18 (Harvard, 8-bit data / 16-bit instruction) |
| Program Memory (Flash) | 32 KB (16K x 16 words) |
| RAM | 2 KB |
| EEPROM | 256 bytes |
| Max CPU Frequency | 48 MHz |
| Supply Voltage (Vdd) | 1.8 V to 3.6 V |
| I/O Pins | 36 |
| ADC | 10-bit, up to 28 channels |
| Communication | 2x EUSART, 2x MSSP (SPI/I2C) |
| Timers | Up to 7 (16-bit / 8-bit mix) |
| Package | 40-pin PDIP (0.600", 15.24 mm) |
| Mounting Type | Through-Hole (DIP) |
| Operating Temperature | -40C to +125C (Extended, "-E" suffix) |
| RoHS Status | Compliant (lead-free) |
PIC18LF45K22-E/P Pin Configuration
| Pin 1 | MCLR/RE3 — Reset input / digital input only on port E bit 3 |
| Pin 2 | RA0/AN0/C1INA/ULPWU — PORTA bit 0 / analog input 0 / comparator 1 input / ultra-low-power wake-up |
| Pin 3 | RA1/AN1/C2INA/CTDIN — PORTA bit 1 / analog input 1 / comparator 2 input / CTMU digital input |
| Pin 4 | RA2/AN2/Vref-/CVref — PORTA bit 2 / analog input 2 / ADC voltage reference low / comparator voltage reference |
| Pin 5 | RA3/AN3/Vref+ — PORTA bit 3 / analog input 3 / ADC voltage reference high |
| Pin 6 | RA4/T0CKI/C1OUT — PORTA bit 4 / Timer0 clock input / comparator 1 output |
| Pin 7 | RA5/AN4/C2OUT/SRNQ — PORTA bit 5 / analog input 4 / comparator 2 output / SR latch NOT-Q |
| Pin 8 | RE0/RD/AN5 — PORTE bit 0 / LCD segment drive / analog input 5 |
| Pin 9 | RE1/WR/AN6 — PORTE bit 1 / LCD segment drive / analog input 6 |
| Pin 10 | RE2/CS/AN7 — PORTE bit 2 / LCD segment drive / analog input 7 |
| Pin 11 | VDD — Positive supply (1.8 V to 3.6 V) |
| Pin 12 | VSS — Ground reference |
| Pin 13 | OSC1/CLKIN/RA7 — Crystal oscillator input / external clock in / PORTA bit 7 |
| Pin 14 | OSC2/CLKOUT/RA6 — Crystal oscillator output / system clock output / PORTA bit 6 |
| Pin 15 | RC0/SOSCO — PORTC bit 0 / secondary oscillator output (32.768 kHz) |
| Pin 16 | RC1/SOSCI — PORTC bit 1 / secondary oscillator input (32.768 kHz) |
| Pin 17 | RC2/CCP1 — PORTC bit 2 / Capture/Compare/PWM 1 |
| Pin 18 | RC3/SCL1/SCK1 — PORTC bit 3 / MSSP1 I2C clock / MSSP1 SPI clock |
| Pin 19 | RD0/PSP0/AN8/SEG0 — PORTD bit 0 / parallel slave port data / analog input 8 / LCD segment 0 |
| Pin 20 | RD1/PSP1/AN9/SEG1 — PORTD bit 1 / parallel slave port data / analog input 9 / LCD segment 1 |
| Pin 21 | RD2/PSP2/AN10/SEG2 — PORTD bit 2 / parallel slave port data / analog input 10 / LCD segment 2 |
| Pin 22 | RD3/PSP3/AN11/SEG3 — PORTD bit 3 / parallel slave port data / analog input 11 / LCD segment 3 |
| Pin 23 | RC4/SDI1/SDA1 — PORTC bit 4 / MSSP1 SPI data in / MSSP1 I2C data |
| Pin 24 | RC5/SDO1 — PORTC bit 5 / MSSP1 SPI data out |
| Pin 25 | RC6/TX1/CK1 — PORTC bit 6 / EUSART1 transmit / EUSART1 clock |
| Pin 26 | RC7/RX1/DT1 — PORTC bit 7 / EUSART1 receive / EUSART1 data |
| Pin 27 | RD4/PSP4/AN12/SEG4 — PORTD bit 4 / parallel slave port data / analog input 12 / LCD segment 4 |
| Pin 28 | RD5/PSP5/AN13/SEG5 — PORTD bit 5 / parallel slave port data / analog input 13 / LCD segment 5 |
| Pin 29 | RD6/PSP6/AN14/SEG6 — PORTD bit 6 / parallel slave port data / analog input 14 / LCD segment 6 |
| Pin 30 | RD7/PSP7/AN15/SEG7 — PORTD bit 7 / parallel slave port data / analog input 15 / LCD segment 7 |
| Pin 31 | VSS — Ground reference |
| Pin 32 | VDD — Positive supply (1.8 V to 3.6 V) |
| Pin 33 | RB0/AN12/INT0/FLT0/SEG8 — PORTB bit 0 / analog input 12 / external interrupt 0 / PWM fault 0 / LCD segment 8 |
| Pin 34 | RB1/AN10/INT1/SEG9 — PORTB bit 1 / analog input 10 / external interrupt 1 / LCD segment 9 |
| Pin 35 | RB2/AN8/INT2/SEG10 — PORTB bit 2 / analog input 8 / external interrupt 2 / LCD segment 10 |
| Pin 36 | RB3/AN9/CCP2/SEG11 — PORTB bit 3 / analog input 9 / Capture/Compare/PWM 2 / LCD segment 11 |
| Pin 37 | RB4/KBI0/AN11/SEG12 — PORTB bit 4 / interrupt-on-change / analog input 11 / LCD segment 12 |
| Pin 38 | RB5/KBI1/AN13/SEG13 — PORTB bit 5 / interrupt-on-change / analog input 13 / LCD segment 13 |
| Pin 39 | RB6/KBI2/PGC/ICSPCLK — PORTB bit 6 / interrupt-on-change / ICSP clock (programming/debug) |
| Pin 40 | RB7/KBI3/PGD/ICSPDAT — PORTB bit 7 / interrupt-on-change / ICSP data (programming/debug) |
Typical Applications
PIC18LF45K22-E/P is suitable for 7 applications: Battery-Powered Wireless Sensor Node, Handheld Medical Measurement Device, Industrial Control Panel HMI, Portable Data Logger / Instrumentation, USB-CDC Peripheral Bridge Device, Educational Microcontroller Teaching Platform, Capacitive-Touch User Interface.
Battery-Powered Wireless Sensor Node
The PIC18LF45K22-E/P's nanoWatt XLP technology enables sub-uA sleep currents around 20 nA typical with Watchdog Timer enabled, allowing multi-year operation on a 2x AA or Li-primary cell. The LF 1.8-3.6 V supply range matches directly with battery voltage, avoiding the need for a boost converter, and the integrated 10-bit ADC with up to 28 channels lets the node digitize multiple sensor inputs without external analog components. Combined with the EUSART and MSSP modules for connecting to a low-power radio transceiver, the K22 is a natural fit for duty-cycled IoT sensor endpoints that wake briefly, sample, transmit, and return to deep sleep.
Recommended
Handheld Medical Measurement Device
The Extended -40C to +125C temperature range of the PIC18LF45K22-E/P supports handheld medical devices that may sit in unheated rooms, ambulances, or refrigerator storage. The 32 KB Flash accommodates complex measurement algorithms, while the 2 KB RAM provides working memory for waveform buffering. Low active current at 48 MHz (about 6 mA) keeps thermal rise minimal for skin-contact thermometry, and the CTMU peripheral enables capacitive touch buttons without external components, simplifying the user interface.
Recommended
Industrial Control Panel HMI
The 36 digital I/O pins of the PIC18LF45K22-E/P can drive keypads, character LCDs, status LEDs, and relay outputs directly without external bus expanders, while the 40-pin PDIP package remains ideal for hand-soldered industrial prototypes and field-serviceable designs. The PIC18 instruction set with hardware multiply accelerates deterministic control loops, and the dual EUSART simplifies RS-232 / RS-485 bridging in industrial protocols. Pan and port-mapped peripherals keep interrupt latency tight for safety-critical control loops.
Recommended
Portable Data Logger / Instrumentation
The 32 KB Flash and 256 bytes of EEPROM of the PIC18LF45K22-E/P enable local storage of calibration constants, user preferences, and small data buffers, while the integrated 10-bit ADC handles multi-channel temperature, voltage, or current monitoring. The LF 1.8-3.6 V supply matches portable battery packs and USB-powered instrumentation, and the nanoWatt XLP deep sleep preserves battery life during standby between logging intervals. The PIC18 core executes deterministic DSP loops for FFT or FIR filtering without external signal-processing ICs.
Recommended
USB-CDC Peripheral Bridge Device
The PIC18LF45K22-E/P's MSSP (SPI/I2C) modules and EUSART allow it to bridge legacy UART peripherals to USB via an external MCP2200 or MCP2221, while the 32 KB Flash can host custom CDC command interpreters. The LF 1.8-3.6 V supply works directly from a USB-powered 3.3 V regulator rail, eliminating the need for a separate power stage. The wide Extended temperature range supports commercial and industrial USB peripherals deployed in harsh environments.
Recommended
Educational Microcontroller Teaching Platform
The 40-pin PDIP package of the PIC18LF45K22-E/P is breadboard-friendly and survives repeated insertion cycles, making it ideal for university laboratories, maker spaces, and hobby platforms. MPLAB X IDE and XC8 compiler support is free, and the PICkit 4 / MPLAB Snap programmers provide in-circuit debugging at low cost. Students can experiment with the on-chip ADC, timers, interrupts, and UART without soldering or surface-mount rework, accelerating curriculum delivery.
Recommended
Capacitive-Touch User Interface
The on-chip CTMU (Charge Time Measurement Unit) of the PIC18LF45K22-E/P enables capacitive-touch buttons, sliders, and proximity sensors without external touch ICs. Combined with the integrated 10-bit ADC for analog measurements and the 32 KB Flash for gesture-recognition firmware, the K22 can replace multiple discrete components in a touch user interface. The LF 1.8-3.6 V supply range matches battery-operated touch interfaces in consumer products.
Recommended
Recommended Products Summary
Engineering reference data for PIC18LF45K22-E/P — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC18LF46K22-E/P | PIC18LF44K22-I/P | PIC18LF45K42-E/P | PIC18F45K22-E/P | PIC18LF46K22-I/P |
|---|---|---|---|---|---|---|
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Package | PDIP-40 (0.600 inch / 15.24 mm) | PDIP-40 - same | PDIP-40 - same | PDIP-40 - same | PDIP-40 - same | PDIP-40 - same |
| Program Memory (Flash) | 32 KB (16K x 16) | 64 KB (+100%) | 16 KB (-50%) | 32 KB (same) | 32 KB (same) | 64 KB (+100%) |
| RAM | 2 KB | 2 KB (same) | 1 KB (-50%) | 2 KB (same) | 2 KB (same) | 2 KB (same) |
| Supply Voltage (Vdd) | 1.8 V to 3.6 V (LF) | 1.8 V to 3.6 V (LF) | 1.8 V to 3.6 V (LF) | 1.8 V to 3.6 V (LF) | 1.8 V to 5.5 V (F) | 1.8 V to 3.6 V (LF) |
| Maximum CPU Frequency | 48 MHz (12 MIPS) | 48 MHz (same) | 48 MHz (same) | 64 MHz (faster) | 48 MHz (same) | 48 MHz (same) |
| I/O Pins | 36 | 36 (same) | 36 (same) | 36 (same) | 36 (same) | 36 (same) |
| Operating Temperature | -40C to +125C (Extended, '-E') | -40C to +125C (Extended) | 0C to +85C (Industrial, '-I') | -40C to +125C (Extended) | -40C to +125C (Extended) | 0C to +85C (Industrial) |
| Core Family | PIC18 XLP K22 | PIC18 XLP K22 | PIC18 XLP K22 | PIC18 XLP K42 (newer) | PIC18 XLP K22 (F variant) | PIC18 XLP K22 |
Key Differentiators
- Higher memory density in the same package versus smaller K22 siblings (vs PIC18LF44K22-I/P)
- Lower supply range with identical silicon versus the F variant (vs PIC18F45K22-E/P)
- Extended -40C to +125C temperature range versus Industrial variants (vs PIC18LF44K22-I/P / PIC18LF46K22-I/P)
- Established nanoWatt XLP technology versus newer K42 core (vs PIC18LF45K42-E/P)
Design Notes
Use the nanoWatt XLP Sleep mode (SLEEP instruction with IDLEN=0 and Watchdog Timer configured) to achieve typical deep-sleep currents around 20 nA per Microchip datasheet DS39996. For duty-cycled sensor nodes, exit sleep via WDT timeout (1 second typical at 32 kHz secondary oscillator) or via an external interrupt on RB0-RB7. Estimated battery life: a CR2032 (~220 mAh) powering a sensor node with 99.5 percent sleep duty cycle lasts approximately 4 years before reaching 2.0 V cutoff.
Place the 1 uF bypass capacitor within 5 mm of the VDD pins (11 and 32 on the 40-pin PDIP), and a second 100 nF ceramic close to the MCU. Route the ICSP signals RB6/PGC and RB7/PGD as a short, parallel pair away from switching traces to avoid noise injection during in-circuit programming. Add a 10 kohm pull-up on MCLR (pin 1) to VDD for reliable reset behaviour; the MCLR pin is rated to 13.5 V maximum.
Do not apply voltages above 3.6 V to any I/O pin on the PIC18LF45K22-E/P (LF variant); over-voltage will trigger ESD latch-up. If a 5 V rail is present in your system, select the PIC18F45K22-E/P (F variant, 1.8-5.5 V tolerant) instead. Also verify that the LF device is configured for HFINTOSC with the PLL disabled if you are operating at 3.3 V, since some PLL configurations require minimum 3.0 V to lock reliably.
When using the ADC, isolate the analog traces (RA0-RA5, RE0-RE2, RB0-RB2) from switching nodes such as PWM outputs or the EUSART TX line. The datasheet recommends a ground plane beneath the analog area and ferrite-bead decoupling between AVDD and VDD if you supply the ADC reference from a separate rail. Use the dedicated Vref+ (RA3) and Vref- (RA2) pins instead of tying the reference to VDD for better-than-Vdd/2 noise rejection.
For crystal-oscillator operation above 4 MHz, follow Microchip's oscillator layout guidelines: keep the crystal traces short, place the load capacitors within 5 mm of OSC1 and OSC2, and surround the oscillator area with a ground pour to minimise radiated EMI. For low-power designs, prefer the internal HFINTOSC up to 16 MHz and avoid a crystal entirely; this eliminates the 1-5 mA idle current required to drive an external crystal oscillator.
Compliance Information
RoHS-compliant lead-free PDIP package per Microchip product page. AEC-Q100 qualification status not asserted by manufacturer for this part; for automotive-grade PIC18 parts, see the PIC18FxxKxx-Q1 family instead.
