PIC18F26K42-I/SS - 64KB Flash 8-bit MCU 64MHz XLP | Microchip
MPN: PIC18F26K42-I/SS ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $2.31 | $2.31 |
| 10 | $2.18 | $21.80 |
| 100 | $1.92 | $192.00 |
| 500 | $1.71 | $855.00 |
| 1,000 | $1.55 | $1,550.00 |
PIC18F26K42-I/SS Overview
An 8-bit PIC microcontroller is a RISC-based CMOS device that integrates CPU, Flash program memory, SRAM, EEPROM, and configurable peripherals on a single die. The PIC18 architecture adds a 16-bit wide instruction word, linear program memory up to 2 MB, hardware multiply, and C compiler-friendly assembly. Within the broader taxonomy, PIC18FxxK42 parts sit at the top of the PIC18F eXtreme Low-Power (XLP) tree, optimized for battery-powered and always-on designs that demand sub-uA standby current.
Key features of the PIC18F26K42-I/SS include a 12-bit ADC with Computation (ADC2) supporting up to 35 external channels, a 5-bit DAC, two comparators, a 10-bit PWM with Complementary Waveform Generator (CWG), vector interrupts, DMA, Memory Access Partition (MAP), Device Information Area (DIA), and 25 digital I/O pins. Operating voltage spans 1.8V to 5.5V across -40C to +85C industrial range, with sleep current as low as 50 nA typical thanks to XLP technology.
The device combines an enhanced mid-range core with CIP blocks, enabling event-driven designs that wake the CPU only when needed. Integrated charge pump and hardware CVD automate capacitive touch sensing, while ADC2 oversampling and threshold-comparison post-processing offload sensor-signal conditioning from firmware.
Typical applications include IoT sensor nodes, capacitive touch user interfaces, battery-powered home automation, motor and lighting control via CWG/PWM, and low-cost industrial sensor hubs where 64 KB of Flash and 4 KB RAM are sufficient.
When laying out the PCB, place a 0.1 uF decoupling capacitor within 3 mm of each VDD pin and tie all unused I/O to defined logic levels. For ICSP programming, reserve the PGD/PGC pair and ensure MCLR is pulled up through a resistor.
This page combines distributor pricing, drop-in alternatives from Microchip's PIC18-K42/K40/K22 families, and practical design notes not found in the manufacturer datasheet.
Drop-in alternatives for PIC18F26K42-I/SS — 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/SS (same form factor and footprint) — differing in ADC, Package, DAC, Program Memory (Flash), MSL Level.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PIC18F25K42-I/SS
✅ Drop-In📋 Reference alternative (not in catalog)
PIC18F26K40-I/SS
✅ Drop-In✓ In Stock
$1.85 / Unit
View Datasheet →PIC18F26K22-I/SS
✅ Drop-In📋 Reference alternative (not in catalog)
PIC18F24K42-I/SS
✅ Drop-In✓ In Stock
$1.53 / Unit
View Datasheet →PIC18F26K42-I/SO
✅ Drop-In✓ In Stock
$1.43 / Unit
View Datasheet →PIC18F25K40-I/SS
✅ Drop-In✓ In Stock
$1.1 / Unit
View Datasheet →PIC18F26K42-I/SS Maximum Ratings & Electrical Characteristics
| Core | PIC18 8-bit RISC |
| Maximum CPU Frequency | 64 MHz |
| Program Memory (Flash) | 64 KB (32K x 16) |
| Data SRAM | 4 KB |
| EEPROM | 1 KB |
| Operating Voltage Range | 1.8 V to 5.5 V |
| I/O Pins | 25 |
| ADC | 12-bit ADC2, up to 35 channels |
| DAC | 5-bit |
| Comparators | 2 |
| PWM Channels | 10-bit, multiple channels |
| Package | 28-SSOP (5.30 mm) |
| Operating Temperature | -40C to +85C (Industrial) |
| Mounting Type | Surface Mount |
| RoHS Status | Compliant |
PIC18F26K42-I/SS Pin Configuration
| Pin 1 | MCLR/RE3 — Master Clear (reset) input or digital input RE3 |
| Pin 2 | RA0 — PORTA bit 0 / analog AN0 |
| Pin 3 | RA1 — PORTA bit 1 / analog AN1 |
| Pin 4 | RA2 — PORTA bit 2 / analog AN2 |
| Pin 5 | RA3 — PORTA bit 3 / analog AN3 / VREF+ |
| Pin 6 | RA4 — PORTA bit 4 / analog AN4 |
| Pin 7 | RA5 — PORTA bit 5 / analog AN5 |
| Pin 8 | RA6 — PORTA bit 6 / analog AN6 |
| Pin 9 | RA7 — PORTA bit 7 / analog AN7 |
| Pin 10 | VSS — Ground reference |
| Pin 11 | RB0 — PORTB bit 0 / analog AN8 / IOC |
| Pin 12 | RB1 — PORTB bit 1 / analog AN9 / IOC |
| Pin 13 | RB2 — PORTB bit 2 / analog AN10 / IOC |
| Pin 14 | RB3 — PORTB bit 3 / analog AN11 / IOC |
| Pin 15 | RB4 — PORTB bit 4 / IOC |
| Pin 16 | RB5 — PORTB bit 5 / IOC |
| Pin 17 | RB6 — PORTB bit 6 / PGC (ICSP clock) |
| Pin 18 | RB7 — PORTB bit 7 / PGD (ICSP data) |
| Pin 19 | VSS — Ground reference (second) |
| Pin 20 | VDD — Positive supply voltage |
| Pin 21 | RC0 — PORTC bit 0 |
| Pin 22 | RC1 — PORTC bit 1 |
| Pin 23 | RC2 — PORTC bit 2 |
| Pin 24 | RC3 — PORTC bit 3 / SCL |
| Pin 25 | RC4 — PORTC bit 4 / SDA |
| Pin 26 | RC5 — PORTC bit 5 |
| Pin 27 | RC6 — PORTC bit 6 / TX |
| Pin 28 | RC7 — PORTC bit 7 / RX |
Typical Applications
PIC18F26K42-I/SS is suitable for 6 applications: IoT Sensor Hub with ADC2 Oversampling, Capacitive Touch User Interface, Battery-Powered Home Automation, Motor and Lighting PWM Control, Industrial Sensor Conditioning Hub, USB HID Device with Bootloader.
IoT Sensor Hub with ADC2 Oversampling
The PIC18F26K42-I/SS fits IoT sensor hub designs that aggregate multiple analog inputs from temperature, light, and gas sensors. Its 12-bit ADC2 with hardware oversampling and threshold detection reaches effective 14-bit resolution while the CPU remains in sleep, dropping average current below 1 mA. The 64 KB Flash accommodates MQTT or BLE profiles and the 4 KB RAM supports TLS handshake buffers. Place a 0.1 uF decoupling capacitor within 3 mm of VDD pins and reserve PGD/PGC for ICSP.
Recommended
Capacitive Touch User Interface
The PIC18F26K42-I/SS integrates hardware Capacitive Voltage Divider (CVD) that automates touch sampling without CPU intervention, making it ideal for HMI panels and appliance front panels. The CVD block handles up to 35 channels, supports driven shield for waterproofing, and runs in Sleep mode for sub-uA standby. Combined with the 5-bit DAC for LED backlight dimming and 25 GPIO for matrix scanning, this MCU consolidates touch + display driver in one 28-SSOP part.
Recommended
Battery-Powered Home Automation
The PIC18F26K42-I/SS suits battery-powered home automation devices such as door/window sensors, smart locks, and PIR motion detectors that spend most of their life in Sleep. With XLP technology delivering 50 nA typical sleep current and DMA waking the CPU only on peripheral events, a single CR2032 can power the node for 5+ years. The integrated ADC2 monitors battery voltage without external components and the 1 KB EEPROM stores calibration and node IDs across power cycles.
Recommended
Motor and Lighting PWM Control
The PIC18F26K42-I/SS drives small DC motors, LED arrays, and half-bridge lighting stages using its 10-bit PWM with Complementary Waveform Generator (CWG) providing dead-band control. The CWG outputs complementary PWM with programmable dead time, eliminating the MCU from the critical timing path and reducing firmware overhead. The 5-bit DAC generates reference voltages for analog control loops, while the comparators provide hardware overcurrent protection that trips within 50 ns.
Recommended
Industrial Sensor Conditioning Hub
The PIC18F26K42-I/SS serves industrial 4-20 mA loop transmitters and RTD bridges where ADC2 with hardware averaging replaces external signal-conditioning ASICs. Hardware oversampling to 14-bit effective resolution meets IEC 61298 accuracy class, while the -40C to +85C industrial temperature range handles factory floor environments. The vector interrupt controller and DMA minimize jitter on time-critical sensor reads, and the 1 KB EEPROM stores calibration coefficients.
Recommended
USB HID Device with Bootloader
The PIC18F26K42-I/SS supports USB device classes through external transceiver plus firmware stacks that fit within 64 KB Flash, making it suitable for HID input devices, CDC virtual COM ports, and custom HID game controllers. The Memory Access Partition (MAP) feature partitions Flash for bootloader + application, enabling field firmware updates without external programmer. DMA offloads USB endpoint memory moves from CPU, freeing cycles for application logic.
Recommended
Recommended Products Summary
Engineering reference data for PIC18F26K42-I/SS — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC18F25K42-I/SS | PIC18F26K40-I/SS | PIC18F26K22-I/SS | PIC18F24K42-I/SS | PIC18F26K42-I/SO | PIC18F25K40-I/SS |
|---|---|---|---|---|---|---|---|
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Package | 28-SSOP | 28-SSOP - same | 28-SSOP - same | 28-SSOP - same | 28-SSOP - same | 28-SOIC (300 mil, larger) | 28-SSOP - same |
| Flash (KB) | 64 | 32 | 64 | 64 | 16 | 64 | 32 |
| RAM (KB) | 4 | 4 | 3 | 3 | 1 | 4 | 2 |
| EEPROM (KB) | 1 | 1 | 1 | 1 | 1 | 1 | 1 |
| Max CPU Freq (MHz) | 64 | 64 | 64 | 64 | 64 | 64 | 64 |
| ADC | 12-bit ADC2 | 12-bit ADC2 | 10-bit ADC | 10-bit ADC | 12-bit ADC2 | 12-bit ADC2 | 10-bit ADC |
| DMA / CIPs | Yes (K42 CIPs) | Yes (K42 CIPs) | No (K40 gen) | No (K22 gen) | Yes (K42 CIPs) | Yes (K42 CIPs) | No (K40 gen) |
| Sleep Current Typ (nA) | 50 | 50 | ~100 | ~100 | 50 | 50 | ~100 |
Key Differentiators
- Hardware ADC2 with oversampling and threshold detection (vs PIC18F26K40-I/SS)
- DMA controller integrated on-chip (vs PIC18F26K22-I/SS)
- 64 KB Flash with 4 KB RAM in 28-SSOP (vs PIC18F24K42-I/SS)
Design Notes
Place a 0.1 uF decoupling capacitor within 3 mm of each VDD pin (pins 20 and 28 on 28-SSOP) and a bulk 10 uF tantalum or ceramic capacitor at the board-level VDD rail. For battery-powered designs operating below 3V, the integrated charge pump still allows Flash programming. Tie unused I/O to defined logic levels (either VDD through 10k or VSS) to minimize sleep current leakage paths.
Reserve RB6 (pin 17) and RB7 (pin 18) as the ICSP clock and data lines and bring them to a header or test pad; do not strap them to external pull-ups that exceed 10k because Microchip programmers drive these pins directly. Place MCLR (pin 1) with a 10k pull-up to VDD and a 100 nF cap to VSS for noise immunity. Keep analog traces (PORTA and PORTB analog-capable pins) short and away from switching nodes to avoid ADC2 coupling.
When using the 12-bit ADC2 at full 64 MHz CPU clock, route the analog reference (VREF+/VREF-) on pins RA3/RA2 with star grounding and a 10 nF ceramic bypass at the pin. Avoid digital switching on adjacent PORTB pins during ADC conversions; alternatively use ADC2 hardware averaging to suppress switching noise. Estimated: with 0.1 inch trace length and ground plane, expect ~2 LSB noise floor.
Do not assume PIC18F25K42-I/SS is a drop-in for firmware over 32 KB - the linker will truncate silently and the device will appear to lock up. Always select the correct device in MPLAB X project properties and verify compiled Flash usage stays under the device limit. Also avoid using pin 1 (MCLR) as RE3 in noisy environments without proper decoupling, as MCLR glitches can cause spurious resets.
Compliance Information
RoHS and REACH compliant per Microchip product page. Industrial -40C to +85C temperature grade only; AEC-Q100 automotive variants are not available in the K42 family. Use PIC18F automotive-grade parts (PIC18FxxK80) for vehicle applications.
