PIC18LF26K42-I/SP - 64KB Flash 8-bit XLP MCU, 28-SPDIP | Microchip
MPN: PIC18LF26K42-I/SP ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $2.79 | $2.79 |
| 10 | $2.65 | $26.50 |
| 100 | $2.4 | $240.00 |
| 500 | $2.18 | $1,090.00 |
| 1,000 | $1.95 | $1,950.00 |
PIC18LF26K42-I/SP Overview
What is a PIC18 XLP microcontroller? PIC18 XLP is Microchip's enhanced 8-bit microcontroller family built on a modified Harvard architecture with C compiler-friendly instruction set, combining large memory with advanced peripherals. Within the broader taxonomy, PIC18 belongs to 8-bit microcontrollers -> microcontrollers (MCUs) -> embedded processors -> semiconductors. The 'LF' prefix denotes the low-voltage (1.8V-3.6V) variant, while XLP denotes deep-sleep currents down to nanoamp levels, targeting IoT, wearables, and portable instrumentation.
Key features include 64MHz internal oscillator, four 16-bit timers, two I2C, two SPI, two UART, 12-bit ADC2 with computation, 5-bit DAC, three op-amps (selected packages), DMA controller, vectored interrupts with hardware context save, and on-chip CIPs such as CWG, NCO, and PWM. The 28-SPDIP package brings 25 programmable I/O pins through Peripheral Pin Select (PPS), allowing flexible routing of digital peripherals to physical pins.
Technically, the K42 family uses a 14-stage instruction pipeline with single-cycle ALU operations and hardware multiplier, supporting both C and assembly development. The DMA engine moves data between memory and peripherals without CPU intervention, freeing the core for low-power sleep. The ADC2 includes averaging, oversampling, and threshold comparisons for sensor conditioning without external DSP.
Typical applications include IoT sensor nodes, low-power wireless sensor hubs, battery-powered medical wearables, HVAC controls, smart energy metering, and USB-to-UART bridges. The wide peripheral set makes it equally suitable for industrial HMI front-ends and consumer white-goods controllers.
When designing with this part, plan for PPS reassignment before committing PCB traces - the same silicon can map UART, I2C, or SPI to almost any I/O pin, but that mapping must be set in firmware. Choose the LF variant only if your system rail is <=3.6V; otherwise migrate to the PIC18F26K42 (F = 2.3V-5.5V).
This page synthesizes verified distributor pricing, drop-in alternatives from the same K42 family, and practical design notes not found in the standalone datasheet, helping engineers select, source, and integrate the PIC18LF26K42-I/SP faster.
Drop-in alternatives for PIC18LF26K42-I/SP — 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/SP (same form factor and footprint) — differing in ADC, Core Architecture, Package, Family, Operating Temperature.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PIC18LF26K42-I/SO
✅ Drop-In✓ In Stock
$1.92 / Unit
View Datasheet →PIC18LF26K42-I/ML
✅ Drop-In✓ In Stock
$2.62 / Unit
View Datasheet →PIC18F26K42-I/SP
✅ Drop-In✓ In Stock
$2.46 / Unit
View Datasheet →PIC18LF26K42-E/SP
✅ Drop-In📋 Reference alternative (not in catalog)
PIC18LF25K42-I/SO
✅ Drop-In ⚠️ Specs Unverified✓ In Stock
$1.62 / Unit
View Datasheet →PIC18LF26K40-I/SP
✅ Drop-In📋 Reference alternative (not in catalog)
PIC18LF26K42-I/SP Maximum Ratings & Electrical Characteristics
| Core Architecture | PIC18 8-bit |
| Series | PIC XLP 18K |
| Family | PIC18FxxK42 / PIC18LFxxK42 |
| Program Memory (Flash) | 64 KB (32K x 16) |
| RAM | 4 KB |
| EEPROM | 1 KB |
| Maximum CPU Frequency | 64 MHz |
| Operating Voltage Range | 1.8 V to 3.6 V (LF variant) |
| ADC | 12-bit ADC2 (multiple channels) |
| DAC | 5-bit DAC |
| Comparators | Yes |
| DMA Controller | Yes |
| I/O Pins (max) | 25 (programmable via PPS) |
| Communication Interfaces | 2x I2C, 2x SPI, 2x UART |
| Timers | 4x 16-bit timers |
| PWM Channels | Yes (multiple channels) |
| Vector Interrupts | Yes (with hardware context save) |
| XLP Technology | Yes (nanoWatt XLP) |
| Package | 28-pin SPDIP (SP) |
| Operating Temperature | -40 C to +85 C (industrial, I grade) |
| Mounting Type | Through-Hole |
| RoHS Status | ROHS3 Compliant |
| Packaging | Tube |
| Lead Time | 52 weeks (manufacturer) |
| Lifecycle Status | Active |
PIC18LF26K42-I/SP 28-pin spdip (sp) Pin Configuration Guide
Pin configuration for PIC18LF26K42-I/SP (28-pin spdip (sp) package). This digital IC includes GPIO, communication interfaces (UART, SPI, I2C), and power pins. Refer to the manufacturer datasheet for alternate pin functions and configuration options. Essential for embedded system design and PCB layout.
No detailed pinout data available for PIC18LF26K42-I/SP.
Refer to the datasheet for full pin configuration.
Typical Applications
PIC18LF26K42-I/SP is suitable for 7 applications: IoT Wireless Sensor Node, Battery-Powered Medical Wearable, HVAC Control and Smart Thermostat, Smart Energy Meter and Sub-Metering, Industrial Sensor Hub and HMI Front-End, USB-to-UART Bridge and Protocol Converter, Consumer White-Goods Controller.
IoT Wireless Sensor Node
The PIC18LF26K42-I/SP fits IoT sensor nodes because its XLP nanoWatt sleep currents (sub-uA typical) and 1.8V-3.6V supply directly support coin-cell and energy-harvesting operation, while the 64KB Flash comfortably holds application firmware plus an OTA bootloader. The 12-bit ADC2 with averaging and oversampling handles temperature, humidity, and gas-sensor readout with on-chip conditioning. CIPs such as the CWG and NCO run autonomously during MCU sleep, reducing wake events and extending battery life. Pair the MCU with a sub-GHz or BLE transceiver for a complete wireless sensor node.
Recommended
Battery-Powered Medical Wearable
Medical wearables benefit from the PIC18LF26K42-I/SP's industrial -40C to +85C temperature range, 1.8V-3.6V supply compatible with single lithium coin cells, and DMA-driven sensor pipelines that minimize CPU activity. The 12-bit ADC2 with computation can sample photoplethysmography (PPG) or temperature sensors while the CIPs perform threshold detection without waking the core. Hardware vectored interrupts with context save accelerate response to medical-event triggers. The 28-SPDIP package aids through-hole prototyping on development boards.
Recommended
HVAC Control and Smart Thermostat
HVAC thermostats leverage the PIC18LF26K42-I/SP's 12-bit ADC2 for thermistor bridge readout, PWM channels for triac-based heater/cooler control, and UART/SPI interfaces for connecting to Wi-Fi or LCD display modules. The 64KB Flash holds control algorithms plus user-interface state machines, while 4KB RAM manages display buffers and scheduling tables. Vectored interrupts prioritize safety-critical over-temperature events. Peripheral Pin Select (PPS) lets the same silicon route I2C and SPI to different PCB pins across product variants.
Recommended
Smart Energy Meter and Sub-Metering
The PIC18LF26K42-I/SP suits smart energy metering with its 12-bit ADC2 sampling current-shunt or CT signals, 64KB Flash for tariff and TOU scheduling, and DMA moving ADC samples to RAM without CPU overhead. The 5-bit DAC and comparators enable power-factor correction signaling, while the UART interfaces to wireless modules (LoRa, Wi-Fi, or PLC). EEPROM stores tamper flags and calibration constants across power cycles. PPS allows flexible pin mapping across single-phase and three-phase meter designs.
Recommended
Industrial Sensor Hub and HMI Front-End
Industrial HMI front-ends use the PIC18LF26K42-I/SP for keypad scanning, LCD driving, and fieldbus bridging. Its 4KB RAM handles display frame buffers, while the 64MHz core executes menu logic with sub-millisecond response. UART and SPI connect to RS-485 transceivers or CAN modules, while DMA manages continuous display refresh. The 28-SPDIP package supports through-hole assembly preferred by some industrial customers. CIPs run background debouncing and rotary-encoder decoding without CPU load.
Recommended
USB-to-UART Bridge and Protocol Converter
Although the PIC18LF26K42-I/SP lacks native USB, its dual UART, dual I2C, and dual SPI make it an ideal protocol converter between industrial buses and host processors. Designers add an external USB-UART IC (e.g., MCP2200 or MCP2221) and use PPS to route the serial stream to any pin. The 64KB Flash holds multi-protocol firmware stacks, and 4KB RAM buffers data bursts. This is a common architecture for legacy equipment modernization where the host side gains USB-C without redesigning the MCU side.
Recommended
Consumer White-Goods Controller
Consumer appliances such as washing machines, dishwashers, and small kitchen equipment use the PIC18LF26K42-I/SP for motor control via PWM, user-interface handling, and safety monitoring. The 12-bit ADC2 reads water level, temperature, and motor current; comparators trigger over-current protection; and vectored interrupts prioritize door-lock and over-temperature events. EEPROM stores user cycles and calibration data across power cycles. XLP sleep helps meet standby-power regulations (<0.5W) for energy-star compliance.
Recommended
Recommended Products Summary
Engineering reference data for PIC18LF26K42-I/SP — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC18LF26K42-I/SO | PIC18LF26K42-I/ML | PIC18F26K42-I/SP | PIC18LF26K42-E/SP | PIC18LF25K42-I/SO | PIC18LF26K40-I/SP |
|---|---|---|---|---|---|---|---|
| Package | 28-SPDIP (SP) | 28-SOIC (SO) | 28-QFN (ML) | 28-SPDIP (SP) - same | 28-SPDIP (SP) - same | 28-SOIC (SO) | 28-SPDIP (SP) - same |
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Flash Memory | 64 KB | 64 KB | 64 KB | 64 KB | 64 KB | 32 KB (-50%) | 64 KB |
| Operating Voltage | 1.8V to 3.6V | 1.8V to 3.6V | 1.8V to 3.6V | 2.3V to 5.5V (+39% upper) | 1.8V to 3.6V | 1.8V to 3.6V | 1.8V to 3.6V |
| Maximum Frequency | 64 MHz | 64 MHz | 64 MHz | 64 MHz | 64 MHz | 64 MHz | 64 MHz |
| RAM | 4 KB | 4 KB | 4 KB | 4 KB | 4 KB | 2 KB (-50%) | 3.6 KB (-10%) |
| Temperature Range | -40C to +85C (Industrial) | -40C to +85C | -40C to +85C | -40C to +85C | -40C to +125C (+47% upper) | -40C to +85C | -40C to +85C |
| ADC Resolution | 12-bit ADC2 with computation | 12-bit ADC2 | 12-bit ADC2 | 12-bit ADC2 | 12-bit ADC2 | 12-bit ADC2 | 10-bit ADC (legacy) |
Key Differentiators
- Largest Flash in 28-pin PIC18LF family at 64KB (vs PIC18LF25K42-I/SO)
- Low-voltage LF operation down to 1.8V (vs PIC18F26K42-I/SP)
- Extended temperature variant available on same footprint (vs PIC18LF26K42-E/SP)
Design Notes
The PIC18LF26K42-I/SP operates from 1.8V to 3.6V (LF variant). For stable operation, place a 100nF decoupling capacitor within 5mm of each VDD pin and a bulk 10uF tantalum or ceramic capacitor near the regulator output. When migrating from the LF to the F variant (PIC18F26K42, 2.3V-5.5V), verify the brown-out reset (BOR) threshold matches your minimum supply voltage to avoid spurious resets. XLP nanoWatt sleep modes can drop quiescent current to sub-uA; ensure unused peripherals are explicitly disabled in firmware to avoid parasitic current draw.
The 28-SPDIP package has higher thermal resistance than QFN or SOIC, but for an MCU with typical 5-15mA active current and 3.3V supply, total dissipation is well below 50mW and thermal management is generally unnecessary. In enclosed industrial cabinets with ambient up to +85C, provide adequate airflow and avoid co-locating the MCU with high-power drivers on the same PCB region. For outdoor applications, choose the E variant (PIC18LF26K42-E/SP) rated to +125C instead of the I variant's +85C.
Use Peripheral Pin Select (PPS) to remap UART, I2C, SPI, and PWM to any digital I/O pin before laying out the PCB. Plan for at least one I2C and one SPI path even if not used initially - this gives layout flexibility for late-stage changes. Place the 32.768kHz crystal (if used for RTCC) close to the SOSCO/SOSCI pins with a ground guard ring to minimize coupling. Route analog traces (ANx, VREF+) away from PWM and digital switching lines to prevent ADC2 noise pickup.
Do not assume any digital I/O pin supports all peripherals - the K42 PPS system allows remapping, but each pin has specific input/output capabilities and analog-overlap conflicts. Read the PPS mapping table in the datasheet before assigning I2C or PWM. Do not leave unused pins floating; configure them as outputs or inputs with the WPU disabled to prevent shoot-through or noise injection. When migrating from PIC18F K22 to K42, note that the ADC was upgraded from 10-bit to 12-bit ADC2 - existing firmware assuming 10-bit scaling must be recalibrated.
Compliance Information
ROHS3 compliant per Microchip product page. AEC-Q100 not qualified - choose AEC-Q100 automotive grade parts from PIC18F K42 automotive family for automotive applications. Lead-free packaging standard.
