PIC18F26K42-I/MX - 8-Bit 64MHz 64KB Flash MCU | Microchip XLP 18K
MPN: PIC18F26K42-I/MX ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $2.4 | $2.40 |
| 10 | $2.16 | $21.60 |
| 100 | $1.92 | $192.00 |
| 500 | $1.68 | $840.00 |
| 1,000 | $1.5 | $1,500.00 |
PIC18F26K42-I/MX Overview
A microcontroller (MCU) is a single-chip computer that combines a CPU core, program memory, RAM, EEPROM and a wide set of peripheral interfaces in one IC. The PIC18 family is Microchip's mid-range 8-bit architecture, sitting between baseline PIC10/12/16 and 16-bit PIC24/dsPIC parts. Within that hierarchy, the K42 sub-family adds aggressive low-power modes (XLP technology with nanoWatt sleep), richer CIP analog and timing blocks, and substantially larger memory than its K22/K20 predecessors, while retaining instruction-set compatibility with legacy PIC18 code.
Key headline specifications include 64 KB (64K x 8) Flash, 4 KB SRAM and 1 KB EEPROM, an internal 64 MHz oscillator with PLL, a 12-bit ADC with up to 35 external channels and hardware post-processing, up to four 16-bit PWM outputs, two I2C/SPI and two UART modules, and a wide 2.3 V to 5.5 V operating supply range with active current below 200 µA/MHz. CIPs such as CLCs (Configurable Logic Cells), DSM, NCO and zero-cross detection let designers implement mixed-signal glue logic in hardware, offloading the CPU.
The device targets applications that demand deterministic 8-bit control with strict energy budgets: battery-powered IoT nodes, sensor signal conditioning, BLDC/PMSM fan and pump control, household appliances, low-cost medical peripherals, USB-HID bridges (via MSSP/USB bridges), lighting ballasts, and automotive body/comfort subsystems (using Q-grade variants).
When routing PCB, place a 100 nF decoupling capacitor within 2 mm of every VDD/AVDD pin and a 1 µF bulk capacitor near the MCU, keep the analog AVSS/AGND star-ground separate from digital GND, and reserve the ICSP programming header footprint for production-line flashing. For sleep-mode designs, confirm all CIPs can still trigger wake-up events before locking down the firmware.
Drop-in alternatives for PIC18F26K42-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 PIC18F26K42-I/MX (same form factor and footprint) — differing in ADC, Comparators, Operating Temperature, Package, DAC.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PIC18F26K42T-I/MX
✅ Drop-In✓ In Stock
$1.62 / Unit
View Datasheet →PIC18F26K42-E/MX
✅ Drop-In✓ In Stock
$1.35 / Unit
View Datasheet →PIC18F26K42-I/MXVAO
✅ Drop-In📋 Reference alternative (not in catalog)
PIC18LF26K42-I/MX
✅ Drop-In✓ In Stock
$1.62 / Unit
View Datasheet →PIC18F25K42-E/MX
✅ Drop-In📋 Reference alternative (not in catalog)
PIC18F26K42-I/MX Maximum Ratings & Electrical Characteristics
| Family | PIC18 XLP 18K |
| Core | PIC18 8-bit RISC |
| Program Memory (Flash) | 64 KB (64K x 8) |
| Data SRAM | 4 KB |
| Data EEPROM | 1 KB |
| Maximum CPU Speed | 64 MHz (16 MIPS / 64 MIPS w/ 4x PLL) |
| Operating Voltage (VDD) | 2.3 V to 5.5 V |
| ADC | 12-bit with computation, up to 35 external channels |
| DAC | 5-bit / 8-bit / 10-bit reference DACs |
| Timers | 8-bit x 4, 16-bit x 4 |
| PWM | Up to four 16-bit PWM outputs |
| UART | 2 |
| SPI / I2C (MSSP) | 2 (configurable SPI/I2C) |
| CIPs (CLC / NCO / DSM) | Configurable Logic Cells, Numerically Controlled Oscillator, Data Signal Modulator |
| Comparators | Two rail-to-rail |
| Core Independent Peripherals | CLC, PWM, ADC2 with math, zero-cross detect, hardware limit timer |
| Operating Temperature | -40 C to +85 C (Industrial, -I) |
| Package | 28-pin UQFN (6x6 mm) with EP |
| Mounting Type | Surface Mount |
| MSL Level | 3 (168 hours) |
| RoHS Status | Compliant |
PIC18F26K42-I/MX Pin Configuration
| Pin 1 | RA0 — Bidirectional I/O / analog input / op-amp output |
| Pin 2 | RA1 — Bidirectional I/O / analog input / op-amp inverting input |
| Pin 3 | RA2 — Bidirectional I/O / analog input / op-amp non-inverting input |
| Pin 4 | RA3 — Bidirectional I/O / analog input |
| Pin 5 | RA4 — Bidirectional I/O / analog input / DAC reference output |
| Pin 6 | RA5 — Bidirectional I/O / analog input |
| Pin 7 | RA6 — Bidirectional I/O / analog input / oscillator output |
| Pin 8 | RA7 — Bidirectional I/O / analog input / oscillator input |
| Pin 9 | VSS — Ground reference |
| Pin 10 | RB0 — Bidirectional I/O / interrupt-on-change / programming clock |
| Pin 11 | RB1 — Bidirectional I/O / interrupt-on-change / programming data |
| Pin 12 | RB2 — Bidirectional I/O / interrupt-on-change |
| Pin 13 | RB3 — Bidirectional I/O / interrupt-on-change |
| Pin 14 | RB4 — Bidirectional I/O / interrupt-on-change |
| Pin 15 | RB5 — Bidirectional I/O / interrupt-on-change |
| Pin 16 | RB6 — Bidirectional I/O / interrupt-on-change / ICD clock |
| Pin 17 | RB7 — Bidirectional I/O / interrupt-on-change / ICD data |
| Pin 18 | AVDD — Analog supply voltage |
| Pin 19 | VSS — Ground reference |
| Pin 20 | RC0 — Bidirectional I/O / analog input |
| Pin 21 | RC1 — Bidirectional I/O / analog input |
| Pin 22 | RC2 — Bidirectional I/O / analog input |
| Pin 23 | RC3 — Bidirectional I/O / analog input / MSSP clock |
| Pin 24 | RC4 — Bidirectional I/O / analog input / MSSP data |
| Pin 25 | RC5 — Bidirectional I/O / analog input |
| Pin 26 | RC6 — Bidirectional I/O / UART TX |
| Pin 27 | RC7 — Bidirectional I/O / UART RX |
| Pin 28 | MCLR — Master clear reset (active-low) / VPP programming voltage |
Typical Applications
PIC18F26K42-I/MX is suitable for 8 applications: Battery-Powered IoT Sensor Nodes, Brushless DC Fan and Pump Motor Control, Household Appliance Control Boards, LED Lighting Ballasts and Drivers, Industrial Sensor Signal Conditioning, Low-Cost Medical Peripherals, USB HID Bridges and Custom Interfaces, Automotive Body and Comfort Subsystems.
Battery-Powered IoT Sensor Nodes
The PIC18F26K42-I/MX fits battery-powered IoT sensor endpoints thanks to its XLP nanoWatt technology with sub-µA sleep currents, 64 KB Flash for sensor-fusion firmware, and 1 KB EEPROM for persistent calibration data. At active currents typically below 200 µA/MHz and a 64 MHz CPU, designers can sample sensors, run CIPs and return to sleep while sustaining multi-year coin-cell battery life on wireless nodes using the 2 MSSP (SPI/I2C) ports.
Recommended
Brushless DC Fan and Pump Motor Control
The PIC18F26K42-I/MX drives BLDC and PMSM motor control loops via its four 16-bit PWM channels, two rail-to-rail comparators and ADC2 with hardware math. CIPs such as CLCs and NCO allow zero-cross detection, back-EMF sampling and dead-time insertion without CPU load, while the 64 MIPS throughput closes the commutation loop in well under 1 µs, enabling quiet, efficient fan and pump drives for HVAC and appliance markets.
Recommended
Household Appliance Control Boards
The PIC18F26K42-I/MX anchors washing machine, dishwasher and microwave control boards with its 25 I/O pins driving relays, triac firing via zero-cross detect, and capacitive touch via the CLC + ADC2 combination. The 64 KB Flash holds lookup tables for sensor calibration, the 4 KB SRAM buffers UI state, and the wide 2.3-5.5 V supply connects directly to rectified 5 V rails without additional regulation, reducing BOM cost.
Recommended
LED Lighting Ballasts and Drivers
The PIC18F26K42-I/MX implements dimmable LED ballasts via PWM plus the 12-bit ADC2 measuring photodiode feedback, with CLCs mixing analog feedback and PWM for hybrid dimming curves. The 64 KB Flash stores custom dim profiles, the 1 KB EEPROM retains last-user settings across power cycles, and the 64 MIPS throughput handles DALI or DMX protocol stacks alongside the lighting control loop on the UART modules.
Recommended
Industrial Sensor Signal Conditioning
The PIC18F26K42-I/MX conditions 4-20 mA loop, thermocouple and bridge sensor signals through its 12-bit ADC2 with automated oversampling and threshold comparison, offloading CPU in long acquisition sequences. The 64 KB Flash fits MODBUS or IO-Link protocol stacks, the 2 UARTs run dual buses, and the 28-pin UQFN package fits in compact DIN-rail modules with analog front ends using MCP6S-series op-amps.
Recommended
Low-Cost Medical Peripherals
The PIC18F26K42-I/MX serves portable medical peripherals like pulse oximeters, glucose meters and nebulizers where its XLP nanoWatt sleep extends battery life beyond patient-usable duration. The 12-bit ADC2 with hardware averaging and oversampling meets clinical-grade accuracy for optical sensors, the 64 KB Flash stores calibration lookup tables, and the CLC + comparator block implements hardware over-current protection on motor-driven devices.
Recommended
USB HID Bridges and Custom Interfaces
The PIC18F26K42-I/MX bridges UART/SPI peripherals to USB hosts via companion MCP2200/MCP2221 USB-UART/USB-I2C chips while running user interface logic on its 64 MIPS core. The 2 UARTs plus 2 MSSP modules host up to 4 concurrent serial channels, the 64 KB Flash fits composite USB descriptor tables, and the 28-pin UQFN enables compact dongle designs for configuration, debug and field programming tasks.
Recommended
Automotive Body and Comfort Subsystems
The PIC18F26K42-I/MX runs body-comfort modules like seat controllers, mirror adjusters and interior lighting using its PWM channels and LIN-friendly UART. For AEC-Q100 qualified variants the -E temperature grade or -MXVAO automotive-qualified factory variant operates from -40 C to +125 C. The 64 KB Flash accommodates LIN 2.1 stacks, the 4 KB RAM buffers touch events on capacitive sense implementations, and the UQFN-28 footprint fits compact in-door modules.
Recommended
Recommended Products Summary
Engineering reference data for PIC18F26K42-I/MX — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC18F26K42T-I/MX | PIC18F26K42-E/MX | PIC18F26K42-I/MXVAO | PIC18LF26K42-I/MX | PIC18F25K42-E/MX |
|---|---|---|---|---|---|---|
| Package | 28-UQFN (6x6 mm) | 28-UQFN (6x6 mm) - same | 28-UQFN (6x6 mm) - same | 28-UQFN (6x6 mm) - same | 28-UQFN (6x6 mm) - same | 28-UQFN (6x6 mm) - same |
| Brand | 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%) |
| SRAM | 4 KB | 4 KB | 4 KB | 4 KB | 4 KB | 2 KB (-50%) |
| Operating Voltage | 2.3 V to 5.5 V | 2.3 V to 5.5 V | 2.3 V to 5.5 V | 2.3 V to 5.5 V | 1.8 V to 3.6 V | 2.3 V to 5.5 V |
| Operating Temperature | -40 C to +85 C | -40 C to +85 C | -40 C to +125 C | -40 C to +125 C (automotive qualified) | -40 C to +85 C | -40 C to +125 C |
| Max CPU Speed | 64 MHz (16 MIPS) | 64 MHz (16 MIPS) | 64 MHz (16 MIPS) | 64 MHz (16 MIPS) | 64 MHz (16 MIPS) | 64 MHz (16 MIPS) |
| EEPROM | 1 KB | 1 KB | 1 KB | 1 KB | 1 KB | 256 B (-75%) |
| Pin Count | 28 | 28 - same | 28 - same | 28 - same | 28 - same | 28 - same |
Key Differentiators
- CIP-rich K42 architecture with ADC2 math acceleration (vs PIC18F25K22-I/SS)
- XLP nanoWatt sleep technology with sub-µA currents (vs PIC18F46K42-I/P)
- Compact 28-UQFN (6x6 mm) footprint for space-constrained designs (vs PIC18F46K42-I/P)
- AEC-Q100 automotive grade factory variant available (vs PIC18F25K42-E/MX)
Design Notes
Place a 100 nF ceramic decoupling capacitor within 2 mm of every VDD and AVDD pin, plus a single 1 µF bulk capacitor near the MCU supply pin. Estimated: with 64 MHz CPU, eight 100 nF caps in parallel supply transient current above 200 mA peaks; the 1 µF bulk handles sub-µs in-rush from PWM-driven loads. For XLP sleep, AVDD must remain above 2.0 V for retention; place MCP1700 or MCP1640 LDO upstream to avoid brown-out resets.
The 28-UQFN package dissipates modest power in normal use (below 50 mW at 64 MHz active), but the exposed thermal pad (EP) must be soldered to a copper pad stitched to VSS for ground-plane thermal relief. Estimated: with 6x6 mm UQFN thermal pad at 0.5 oz copper pour, theta_JA is approximately 30 C/W, sufficient for industrial -40 C to +85 C operation without a heatsink at typical active currents.
Use a four-layer PCB with separate analog and digital ground planes tied at one star point beneath the MCU. Keep analog signal traces (RA0-RA5, RC0-RC5) short and far from PWM outputs to avoid coupling. Route the ICSP header footprint (RB6=ICSPCLK, RB7=ICSPDAT, MCLR=VPP) to a 5-pin 2.54 mm header for production-line programming, and keep MCLR pull-up above 4.7 kohm to ensure clean reset behavior.
Do not connect the CLC outputs to pins that conflict with peripheral remap functions without consulting the PPS (Peripheral Pin Select) table in datasheet 40001919B. Many PIC18F26K42 remappable pins default to off after reset - forgetting PPS initialization is the most common cause of 'dead MCU on fresh PCB' symptom. Also note the ADC2 reference voltage selection must precede calibration for accurate readings; default 2.5 V reference is software-selectable.
Compliance Information
RoHS and lead-free per Microchip product page. Industrial -I grade -40 C to +85 C; for AEC-Q100 automotive use choose the -MXVAO factory variant or PIC18F26K42-E/MX extended temperature grade.
