PIC18LF26K42-I/MX - 64KB Flash 8-bit MCU, 64MHz XLP | Microchip
MPN: PIC18LF26K42-I/MX ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $3.18 | $3.18 |
| 10 | $2.92 | $29.20 |
| 100 | $2.45 | $245.00 |
| 500 | $2.12 | $1,060.00 |
| 1,000 | $1.85 | $1,850.00 |
| 3,000 | $1.62 | $4,860.00 |
PIC18LF26K42-I/MX Overview
A microcontroller (MCU) is an integrated circuit that combines a CPU core, program memory (Flash), data memory (RAM), and a range of on-chip peripherals such as timers, communication interfaces, and analog blocks. Within the broader taxonomy, the PIC18LF26K42 sits in the 8-bit MCU category, under microcontrollers, under integrated circuits. The "LF" suffix indicates Microchip's low-power (XLP - eXtreme Low Power) family, optimized for battery-powered and energy-harvesting applications where nanoWatt sleep currents are critical. The "K42" denotes a feature-rich family with extensive CIP integration and high-resolution analog.
Key differentiating features include the 12-bit ADC2 with automated accumulation, averaging, and threshold comparisons offloaded from the CPU, and the Peripheral Pin Select (PPS) that remaps most digital I/O functions to any pin. With 25 usable I/O pins on the 28-pin UQFN footprint and four 16-bit timers, the device delivers high I/O density for its package size. Sleep current is rated in the nanoWatt range with multiple power-managed modes (DOZE, IDLE, SLEEP) and an on-chip voltage reference. The integrated DMA enables background data movement between ADC results and memory buffers, freeing CPU cycles for application logic.
Architecturally, the PIC18F26K42 uses a RISC-based 8-bit core with a 16-bit instruction word, an 8-level hardware stack, and C-compiler-friendly architecture. The Microchip MPLAB X IDE with XC8 compiler provides free and commercial development toolchains, and the device is supported by the MPLAB Code Configurator (MCC) for graphical peripheral setup. The same die is offered in 28/40/48-pin variants, and the LF (low-voltage) and F (full-voltage) versions are pin-compatible, simplifying dual-sourcing strategies.
Typical applications include low-power IoT sensor nodes, battery-powered medical monitors (e.g., glucose meters, pulse oximeters), industrial HMI panels, USB-CDC/HID peripherals, and consumer remote controls. The XLP nanoWatt technology and integrated DMA make it well-suited to always-on edge devices running from a coin cell or energy harvester. In automotive body electronics and aftermarket accessories, the wider PIC18F26K42 family is also commonly deployed.
When designing with this part, note that the LF variant is limited to 3.6V maximum; for designs requiring 5V tolerance, choose the F variant (PIC18F26K42-I/MX). The exposed pad of the UQFN-28 package must be soldered to the PCB ground plane for thermal dissipation and electrical performance; missing the pad connection can cause latch-up or logic errors.
This page synthesizes distributor pricing, drop-in same-package alternatives, and practical design notes not found in the manufacturer datasheet, helping procurement and engineering teams select, source, and design with the PIC18LF26K42-I/MX more efficiently.
Drop-in alternatives for PIC18LF26K42-I/MX — 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 PIC18LF26K42-I/MX (same form factor and footprint) — differing in ADC, Operating Temperature, Package, Program Memory (Flash), Comparators.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PIC18F26K42-I/MX
✅ Drop-In✓ In Stock
$1.5 / Unit
View Datasheet →PIC18LF26K42-I/ML
✅ Drop-In✓ In Stock
$2.62 / Unit
View Datasheet →PIC18LF26K42-E/MX
✅ Drop-In📋 Reference alternative (not in catalog)
PIC18LF25K42-I/MX
✅ Drop-In📋 Reference alternative (not in catalog)
PIC18F25K42-I/MX
✅ Drop-In📋 Reference alternative (not in catalog)
PIC18LF26K42T-I/MX
✅ Drop-In✓ In Stock
$1.72 / Unit
View Datasheet →PIC18LF26K42-I/MX Maximum Ratings & Electrical Characteristics
| Series | PIC® XLP™ 18K (PIC18F K42 family) |
| Core | PIC18 8-bit RISC |
| Program Memory (Flash) | 64 KB (64K x 8) |
| Data RAM | 4 KB |
| EEPROM | 1 KB |
| Maximum CPU Clock | 64 MHz |
| Data Bus Width | 8 bit |
| ADC | 12-bit ADC2 (with computation) |
| DAC | 5-bit DAC |
| Comparators | 3 analog comparators |
| DMA Channels | 2 |
| PWM Channels | Multiple (peripherals: CCP, PWM, CWG) |
| Number of I/O Pins | 25 |
| Operating Supply Voltage (LF) | 1.8 V to 3.6 V |
| Operating Temperature | -40 C to +85 C (Industrial -I) |
| Package | 28-pin UQFN (6x6 mm) with exposed pad |
| Mounting Type | Surface Mount |
| Low-Power Technology | XLP (eXtreme Low Power) nanoWatt |
| Peripheral Pin Select | Yes |
| Vector Interrupts | Yes |
| RoHS Status | Compliant |
PIC18LF26K42-I/MX Pin Configuration
| Pin 1 | RA5 — I/O port A bit 5 / PPS-capable |
| Pin 2 | RA4 — I/O port A bit 4 / PPS-capable |
| Pin 3 | RA3 — I/O port A bit 3 / PPS-capable |
| Pin 4 | RA2 — I/O port A bit 2 / PPS-capable |
| Pin 5 | RA1 — I/O port A bit 1 / PPS-capable |
| Pin 6 | RA0 — I/O port A bit 0 / PPS-capable |
| Pin 7 | VSS — Ground reference |
| Pin 8 | RA7 — I/O port A bit 7 / OSC1 |
| Pin 9 | RA6 — I/O port A bit 6 / OSC2 |
| Pin 10 | RC0 — I/O port C bit 0 / PPS-capable |
| Pin 11 | RC1 — I/O port C bit 1 / PPS-capable |
| Pin 12 | RC2 — I/O port C bit 2 / PPS-capable |
| Pin 13 | RC3 — I/O port C bit 3 / PPS-capable |
| Pin 14 | RC4 — I/O port C bit 4 / PPS-capable |
| Pin 15 | RC5 — I/O port C bit 5 / PPS-capable |
| Pin 16 | RC6 — I/O port C bit 6 / PPS-capable |
| Pin 17 | RC7 — I/O port C bit 7 / PPS-capable |
| Pin 18 | VSS — Ground reference (secondary) |
| Pin 19 | VDD — Positive supply voltage (1.8V-3.6V) |
| Pin 20 | RB0 — I/O port B bit 0 / PPS-capable |
| Pin 21 | RB1 — I/O port B bit 1 / PPS-capable |
| Pin 22 | RB2 — I/O port B bit 2 / PPS-capable |
| Pin 23 | RB3 — I/O port B bit 3 / PPS-capable |
| Pin 24 | RB4 — I/O port B bit 4 / PPS-capable |
| Pin 25 | RB5 — I/O port B bit 5 / PPS-capable |
| Pin 26 | RB6 — I/O port B bit 6 / ICSCLK |
| Pin 27 | RB7 — I/O port B bit 7 / ICSDAT |
| Pin 28 | VDD — Positive supply voltage (secondary) |
Typical Applications
PIC18LF26K42-I/MX is suitable for 7 applications: Battery-Powered IoT Sensor Nodes, Portable Medical Devices, Industrial HMI Panels and Operator Consoles, USB-CDC / HID Peripherals, Consumer Remote Controls and Wireless Key Fobs, Automotive Body Electronics Accessories, Smart Sensor Hubs and Edge Devices.
Battery-Powered IoT Sensor Nodes
The PIC18LF26K42-I/MX is an excellent fit for battery-powered IoT sensor nodes because of its XLP nanoWatt technology and integrated DMA that moves ADC readings to memory without CPU intervention. With a typical sleep current below 100 nA (per Microchip datasheet) and a 1.8V minimum supply that operates directly from a single alkaline cell, this MCU supports multi-year coin-cell deployments. The 12-bit ADC2 with hardware accumulation allows autonomous threshold-based wake-up, while the 64KB Flash fits typical LoRa/BLE sensor stacks. The exposed pad of the UQFN package provides thermal relief for periodic high-current transmit bursts, and the 28-pin UQFN footprint is small enough for sub-10x10mm sensor PCBs.
Recommended
Portable Medical Devices
The PIC18LF26K42-I/MX suits portable medical devices such as glucose meters, pulse oximeters, and portable ECG front-ends due to its low-noise 12-bit ADC2, low power consumption, and integrated analog comparators for signal conditioning. The ADC2's computation engine performs averaging and threshold detection in hardware, offloading the CPU and reducing active-mode current for longer battery life. With 1KB EEPROM available for storing calibration constants and patient log data (10k erase/write cycles minimum), plus robust CIP peripherals that simplify FDA validation, this MCU is widely deployed in clinical and home-health products. The -40C to +85C industrial temperature range covers body-worn applications and ambient operating conditions.
Recommended
Industrial HMI Panels and Operator Consoles
The PIC18LF26K42-I/MX drives industrial HMI panels and operator consoles with its 64MHz CPU, 64KB Flash for graphical LCD/TFT menu stacks, and 25 I/O pins for keypad scanning, LED indicators, and buzzer control. The Peripheral Pin Select (PPS) feature allows the SPI/I2C/UART interfaces to be remapped to any I/O pin, simplifying PCB routing in space-constrained HMI modules. Three analog comparators handle overcurrent/voltage monitoring, while the 12-bit ADC2 reads potentiometers and analog sensors. The 4KB RAM supports mid-sized text buffers and small display framebuffers. The UQFN-28 footprint fits in tight display module enclosures, and the wide operating temperature (with the -E variant extending to +125C) supports factory-floor environments.
Recommended
USB-CDC / HID Peripherals
The PIC18LF26K42-I/MX family supports USB 2.0 full-speed device operation via Microchip's USB stack, making this MCU an excellent fit for USB-CDC (virtual COM port) and USB-HID peripherals such as data loggers, configuration tools, and custom input devices. The integrated DMA channels move USB endpoint data to RAM without CPU cycles, leaving the 64MHz core free for application logic. With 64KB Flash and 4KB RAM, the device fits the typical USB stack (Microchip MLA) plus substantial application code. Designers should choose the PIC18F26K42 (F variant, 5V-tolerant) for designs that interface directly to USB bus-powered 5V supplies; the LF variant requires a 3.3V LDO on the USB rail.
Recommended
Consumer Remote Controls and Wireless Key Fobs
The PIC18LF26K42-I/MX is a strong match for consumer remote controls, RF key fobs, and BLE beacon peripherals due to its nanoWatt sleep current and quick wake-up time. A typical coin-cell-powered key fob spends 99% of its time in sleep mode and wakes briefly on button press to transmit; the MCU's sub-microamp sleep current (per Microchip XLP datasheet) extends battery life to 3-5 years. The integrated 12-bit ADC2 can read battery voltage for low-battery detection, and the PWM peripherals drive IR LEDs or status indicators. The 28-pin UQFN package is small enough to fit inside a standard key-fob housing. Optional PPS lets the designer route SPI/UART to a Nordic nRF24 or equivalent 2.4GHz transceiver with minimal PCB area.
Recommended
Automotive Body Electronics Accessories
The PIC18LF26K42-I/MX is widely used in automotive aftermarket accessories, body controllers, and interior lighting modules where moderate temperature and 12V-battery-tolerant signal interfacing are required (typically via an external voltage regulator and current limiters). With 12-bit ADC2, multiple PWM channels for LED dimming, and CAN-ready timer peripherals, the MCU handles RGB ambient lighting, seat controllers, and HVAC auxiliaries. Designers should note that the LF variant tops out at 3.6V; automotive designs typically use an external 5V or 3.3V regulator from the 12V battery rail. The 64KB Flash and 4KB RAM fit small RTOS-free control loops for accessory modules.
Recommended
Smart Sensor Hubs and Edge Devices
The PIC18LF26K42-I/MX excels as a smart sensor hub for edge devices that aggregate multiple sensor inputs (temperature, humidity, motion, light) and pre-process data before forwarding. Its 12-bit ADC2 with up to 24 channels (analog) and two DMA controllers let the MCU autonomously scan and store sensor readings, with the CPU waking only when thresholds are crossed. The 1KB EEPROM stores calibration data and unit IDs persistently, and the XLP nanoWatt technology keeps the average current draw below 1 mA in typical sensor-scanning duty cycles. Designers can leverage MPLAB Code Configurator (MCC) for graphical peripheral setup, dramatically shortening development time for production edge-node firmware.
Recommended
Recommended Products Summary
Engineering reference data for PIC18LF26K42-I/MX — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC18F26K42-I/MX | PIC18LF26K42-I/ML | PIC18LF25K42-I/MX |
|---|---|---|---|---|
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Package | 28-UQFN (6x6 mm) | 28-UQFN (6x6 mm) - same | 28-QFN (6x6 mm) - same footprint | 28-UQFN (6x6 mm) - same |
| Flash Memory | 64 KB | 64 KB | 64 KB | 32 KB (-50%) |
| RAM | 4 KB | 4 KB | 4 KB | 4 KB |
| Operating Voltage | 1.8 V to 3.6 V | 1.8 V to 5.5 V (wider) | 1.8 V to 3.6 V (same) | 1.8 V to 3.6 V (same) |
| Temperature Grade | -40 C to +85 C (Industrial) | -40 C to +85 C (Industrial) | -40 C to +85 C (Industrial) | -40 C to +85 C (Industrial) |
| Max CPU Clock | 64 MHz | 64 MHz | 64 MHz | 64 MHz |
| ADC | 12-bit ADC2 | 12-bit ADC2 | 12-bit ADC2 | 12-bit ADC2 |
| DMA Channels | 2 | 2 | 2 | 2 |
| Approx. Price (qty 1000) | $1.85 | Similar | Similar | Lower (smaller Flash) |
Key Differentiators
- Wider operating voltage headroom for 5V designs (vs PIC18LF26K42-I/MX (this part))
- More Flash memory for larger firmware (vs PIC18LF25K42-I/MX)
- Extended temperature grade option available in same package (vs PIC18LF26K42-E/MX)
Design Notes
The PIC18LF26K42-I/MX (LF variant) is rated for 1.8V to 3.6V only. Do NOT apply 5V to VDD or to any I/O pin - this will permanently damage the device. For 5V-tolerant designs, choose the PIC18F26K42-I/MX (F variant). Decoupling: place a 100nF ceramic capacitor within 5mm of each VDD pin (pins 19 and 28) directly to the adjacent VSS pin; add a bulk 1uF to 10uF capacitor at the supply rail entry. The internal voltage regulator requires adequate bulk capacitance during sleep-to-active transitions.
The 28-pin UQFN (6x6 mm) package has a center exposed thermal pad (EP) on the underside that MUST be soldered to a corresponding PCB land. The EP is internally bonded to VSS (ground); failing to solder the EP can cause logic errors, latch-up, and reduced thermal performance. Use an array of thermal vias (typically 5-9 vias, 0.3mm drill) under the EP to connect to the inner/ground plane. The QFN land pattern should follow IPC-7351 nominal-density recommendations with 0.4mm pitch.
Configuration bits (fuses) MUST be set correctly before the MCU will run: enable the appropriate oscillator mode (typically INTOSC at 64MHz), disable MCLR if not used (or enable internal pull-up), and configure the BOR (Brown-Out Reset) threshold to match the supply voltage. Using MPLAB X with the XC8 compiler and MCC (MPLAB Code Configurator) avoids most fuse-config pitfalls by generating the correct configuration header files. PPS (Peripheral Pin Select) unlocking sequence must be performed before reassigning digital functions - refer to the datasheet section on PPS.
Route the ICSP clock and data signals (RB6/ICSCLK and RB7/ICSDAT) away from high-frequency switching signals to avoid debug-time interference. Keep the analog inputs (RA0-RA5, RC0-RB5 if used as analog) short and isolated from digital switching traces; place a ground guard ring around analog traces if PCB area allows. The ADC2 reference voltage (VREF+/VREF-) should be bypassed with 100nF ceramic capacitors placed close to the pin. Pin 1 identification on UQFN: a small dot on the top marking indicates pin 1.
Compliance Information
RoHS and REACH compliant per Microchip product page and datasheet. Lead-free finish; halogen-free. Not AEC-Q100 qualified - choose PIC18F26K42 automotive-grade variants (Q-suffix or /VAO suffix) for AEC-Q100 automotive applications.
