PIC18F26K20-I/SP - 64KB Flash 8-Bit MCU, 28-SPDIP | Microchip
MPN: PIC18F26K20-I/SP ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $4.97 | $4.97 |
| 10 | $4.48 | $44.80 |
| 100 | $3.92 | $392.00 |
| 500 | $3.42 | $1,710.00 |
| 1,000 | $2.94 | $2,940.00 |
PIC18F26K20-I/SP Overview
A microcontroller (MCU) is a single-chip computer that integrates a CPU core, non-volatile program memory, working RAM, and configurable peripheral blocks. The PIC18 family is a high-performance 8-bit Harvard-architecture line from Microchip with a rich instruction set, hardware multiplier, and C-friendly architecture that sits hierarchically between legacy baseline PIC16 devices and the 16-bit PIC24/dsPIC families. nanoWatt XLP technology specifically targets low-power applications where sleep current in the nanoamp range and active consumption below 1 mA/MHz are critical.
Key differentiating features of the PIC18F26K20 include 64 KB of self-programmable Flash for field upgrades, 1 KB of EEPROM data storage, a 10-bit ADC with up to 17 input channels, an Enhanced Capture/Compare/PWM (ECCP) module, two analog comparators with steerable reference, and nanoWatt XLP sleep currents as low as 20 nA. The 64 MHz CPU clock (16 MIPS throughput) gives it strong DSP-style math capability versus typical 8-bit MCUs that operate at 20 MHz or less.
Architecturally, the PIC18F26K20 uses a 16-bit instruction word with an 8-bit data path and a modified Harvard bus, supported by a 32-level hardware stack and interrupt controller with vectored priority. The device supports both internal and external oscillator modes, including a low-power 31 kHz internal oscillator and a high-frequency 16 MHz internal oscillator with PLL. This dual-oscillator architecture enables real-time clock operation while running the CPU from a higher-frequency source.
Typical applications include industrial sensor interfaces, low-power remote sensor nodes running on coin cells or harvested energy, USB HID firmware bridges using the dedicated USB 2.0 full-speed peripheral on K-series silicon, small home appliances, motor control with PWM-driven H-bridges, and educational or hobbyist platforms. The wide peripheral mix makes it a strong fit for any 8-bit application that benefits from large Flash.
When designing with this part, mind the 28-pin SPDIP pinout carefully when migrating code from QFN variants - the QFN version has more I/O available because several ground-only pins on SPDIP are used as additional GPIO on smaller packages. Decoupling with 100 nF ceramic close to VDD/AVDD pairs is mandatory for clean ADC readings.
This page synthesizes distributor pricing, drop-in alternatives, and practical design notes not found in the manufacturer datasheet, giving engineers a fast lookup for both procurement and engineering review.
Drop-in alternatives for PIC18F26K20-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 PIC18F26K20-I/SP (same form factor and footprint) — differing in Operating Temperature, ADC, Package, Comparators, Mounting Type.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PIC18F26K20-E/SP
✅ Drop-In✓ In Stock
$2.85 / Unit
View Datasheet →PIC18F25K20-I/SP
✅ Drop-In📋 Reference alternative (not in catalog)
PIC18F26J53-I/SP
✅ Drop-In📋 Reference alternative (not in catalog)
PIC18F26J13-I/SP
✅ Drop-In📋 Reference alternative (not in catalog)
PIC18F2620-I/SP
✅ Drop-In✓ In Stock
$4.75 / Unit
View Datasheet →PIC18F26K20-I/SP Maximum Ratings & Electrical Characteristics
| Family | PIC18FxxK20 (nanoWatt XLP) |
| Core | 8-bit PIC18 Harvard |
| Program Memory (Flash) | 64 KB (32K x 16) |
| Data RAM | 3968 bytes |
| Data EEPROM | 1 KB |
| Maximum CPU Clock | 64 MHz |
| Instruction Throughput | 16 MIPS |
| Supply Voltage (VDD) | 1.8 V to 3.6 V |
| I/O Pins | 25 |
| ADC | 10-bit, up to 17 channels |
| Timers | 4 (Timer0/1/2/3) |
| PWM Channels (ECCP + CCP) | Up to 4 |
| Comparators | 2 with selectable reference |
| Communication | 1x EUSART (LIN-capable), 2x MSSP (SPI/I2C), USB 2.0 FS |
| Operating Temperature | -40C to +85C (industrial, /I) |
| Package | 28-pin SPDIP (SP) |
| Mounting Type | Through-Hole (DIP) |
| RoHS Status | Pb-Free / compliant |
PIC18F26K20-I/SP Pin Configuration
| Pin 1 | MCLR/VPP/RE3 — Master Clear (reset) input / programming voltage / digital input only on RE3 |
| Pin 2 | RA0/AN0/CVREF — PORTA bit 0 / analog input 0 / comparator voltage reference output |
| Pin 3 | RA1/AN1/C1IN- — PORTA bit 1 / analog input 1 / comparator 1 inverting input |
| Pin 4 | RA2/AN2/C2IN- — PORTA bit 2 / analog input 2 / comparator 2 inverting input |
| Pin 5 | RA3/AN3/C2IN+ — PORTA bit 3 / analog input 3 / comparator 2 non-inverting input |
| Pin 6 | RA4/AN4/C1OUT/T0CKI — PORTA bit 4 / analog input 4 / comparator 1 output / Timer0 clock input |
| Pin 7 | RA5/AN5/C2OUT/SS — PORTA bit 5 / analog input 5 / comparator 2 output / SPI slave select |
| Pin 8 | VSS — Ground reference |
| Pin 9 | OSC1/CLKI/RA7 — External oscillator input / system clock input / PORTA bit 7 |
| Pin 10 | OSC2/CLKO/RA6 — External oscillator output / system clock output / PORTA bit 6 |
| Pin 11 | RC0/SOSCO/T1CKI — PORTC bit 0 / secondary oscillator output / Timer1 clock input |
| Pin 12 | RC1/SOSCI/CCP2 — PORTC bit 1 / secondary oscillator input / CCP2 PWM input/output |
| Pin 13 | RC2/CCP1/P1A — PORTC bit 2 / Enhanced CCP1 input/output / PWM 1A output |
| Pin 14 | RC3/SCK/SCL — PORTC bit 3 / SPI clock / I2C clock |
| Pin 15 | RC4/SDI/SDA — PORTC bit 4 / SPI data in / I2C data |
| Pin 16 | RC5/SDO — PORTC bit 5 / SPI data out |
| Pin 17 | RC6/TX/CK — PORTC bit 6 / EUSART TX / EUSART clock |
| Pin 18 | RC7/RX/DT — PORTC bit 7 / EUSART RX / EUSART data |
| Pin 19 | VSS — Ground reference |
| Pin 20 | VDD — Positive supply voltage |
| Pin 21 | RB0/INT0/FLT0/AN12 — PORTB bit 0 / external interrupt 0 / ECCP fault input / analog input 12 |
| Pin 22 | RB1/INT1/AN10 — PORTB bit 1 / external interrupt 1 / analog input 10 |
| Pin 23 | RB2/INT2/AN8 — PORTB bit 2 / external interrupt 2 / analog input 8 |
| Pin 24 | RB3/AN9/CCP2 — PORTB bit 3 / analog input 9 / CCP2 I/O |
| Pin 25 | RB4/AN11/KBI0 — PORTB bit 4 / analog input 11 / interrupt-on-change bit 0 |
| Pin 26 | RB5/KBI1/PGM — PORTB bit 5 / interrupt-on-change bit 1 / LVP programming |
| Pin 27 | RB6/KBI2/PGC — PORTB bit 6 / interrupt-on-change bit 2 / ICSP clock |
| Pin 28 | RB7/KBI3/PGD — PORTB bit 7 / interrupt-on-change bit 3 / ICSP data |
Typical Applications
PIC18F26K20-I/SP is suitable for 6 applications: Low-Power Wireless Sensor Node, USB HID / CDC Bridge Device, Industrial Sensor Interface Module, Small Home Appliance Control, Educational / Hobbyist Development Platform, Motor Control with PWM H-Bridge Drive.
Low-Power Wireless Sensor Node
The PIC18F26K20-I/SP's nanoWatt XLP technology delivers sleep currents as low as approximately 20 nA, making it ideal for battery-powered wireless sensor nodes running on CR2032 coin cells or harvested energy. At 1 MHz active CPU and 3.3 V supply, active current is below 1 mA, so duty-cycled sensor reads followed by deep sleep can extend battery life into multi-year territory. The 10-bit ADC with up to 17 input channels interfaces directly with analog sensors (temperature, light, gas) without an external amplifier. USB is not used in this application, leaving RA4/RA5/Timer1 free for an external 32.768 kHz crystal to drive a real-time clock. Per the Microchip PIC18FxxK20 datasheet sleep-current spec, this part outperforms J-series PIC18 silicon by roughly an order of magnitude.
Recommended
USB HID / CDC Bridge Device
The PIC18F26K20-I/SP's integrated USB 2.0 full-speed peripheral with on-chip transceiver eliminates the external PHY that older PIC18F designs required. By running the 48 MHz USB clock from the internal 8 MHz oscillator + PLL, designers avoid expensive external crystals and bootloaders can ship over USB directly. Common uses include HID input devices (keyboards, mice, custom controls) and CDC virtual COM ports for PC configuration interfaces. The 64 KB Flash is enough for USB stacks plus application code, and 3968 B RAM comfortably handles USB endpoint buffers plus control logic. Note that 28-SPDIP has fewer GPIO than 40/44-pin QFN variants, so designers must budget RA/RB/RC pins carefully when planning a USB plus SPI display plus UART debug design.
Recommended
Industrial Sensor Interface Module
With 1.8 V to 3.6 V operation, 10-bit ADC, dual comparators, and the industrial -40C to +85C temperature grade, the PIC18F26K20-I/SP fits industrial 4-20 mA loop interfaces, Modbus RTU slave nodes, and process control front-ends. The EUSART with LIN capability supports both point-to-point RS-485 and LIN bus slave nodes, while the two MSSP peripherals simultaneously drive SPI sensors and I2C EEPROM. The PIC18F26K20's 16 MIPS throughput allows real-time linearization and digital filtering in firmware without offloading to a coprocessor. To meet IEC 61000-4 ESD requirements, designers typically add TVS diodes on the RS-485 lines; the MCU's ESD rating is HBM 2 kV per the datasheet, which is fine for cabinet-internal mounting.
Recommended
Small Home Appliance Control
Coffee machines, sous-vide cookers, breadmakers, and similar small appliances need just enough Flash for menu-driven UI code, plus the timers and PWM channels that drive heaters, pumps, and buzzers. The PIC18F26K20-I/SP delivers four timer modules and one Enhanced CCP for precise PWM, plus standard CCP for secondary channels - enough for a triac-driven heater plus DC fan control. The 10-bit ADC handles thermistor reads for closed-loop temperature control. Industrial temperature grade and nanoWatt XLP extend shelf life at the retailer and improve field reliability. The 28-SPDIP package is convenient for service technicians, who can swap the MCU without specialized SMT rework tools.
Recommended
Educational / Hobbyist Development Platform
The PIC18F26K20-I/SP's 28-SPDIP form factor drops directly into solderless breadboards, making it the canonical 'stick it on a breadboard and flash it' MCU for educational kits and maker projects. MPLAB X IDE with the XC8 compiler and PICkit 5 programmer supports this device out of the box, and Microchip's free application libraries (USB, TCP/IP, graphics) all target PIC18FxxK20 silicon. The 64 KB Flash accommodates student projects including USB HID mice, MIDI controllers, and IoT bridges. University courses and Arduino-style maker platforms prefer this part for teaching microcontroller fundamentals because every peripheral - ADC, timers, PWM, USB - fits on a single chip with breadboard-friendly pinout.
Recommended
Motor Control with PWM H-Bridge Drive
Brushed DC and small BLDC motors up to a few hundred watts are easily driven from the PIC18F26K20-I/SP using the Enhanced CCP module in full-bridge or half-bridge PWM mode, with the 10-bit ADC measuring back-EMF or current sense. The MCU's 16 MIPS throughput closes a PID loop in well under 1 ms, giving smooth speed and torque control. The 28-SPDIP is appropriate for low-current bench motor drivers; designers needing more I/O for fault detection or quadrature encoders move to the 40-pin QFN variant. Fail-safe modes (low-power sleep when fault detected) leverage nanoWatt XLP for unattended motor idle states.
Recommended
Recommended Products Summary
Engineering reference data for PIC18F26K20-I/SP — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC18F26K20-I/ML | PIC18F26K20-E/SP | PIC18F25K20-I/SP | PIC18F26J53-I/SP | PIC18F2620-I/SP |
|---|---|---|---|---|---|---|
| Package | 28-SPDIP (SP) | 28-QFN (ML) | 28-SPDIP (SP) - same | 28-SPDIP (SP) - same | 28-SPDIP (SP) - same | 28-SPDIP (SP) - same |
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Program Memory (Flash) | 64 KB | 64 KB - same | 64 KB - same | 32 KB (-50%) | 64 KB - same | 64 KB - same |
| RAM | 3968 B | 3968 B - same | 3968 B - same | 2048 B (-48%) | 3968 B - same | 3986 B - similar |
| Maximum CPU Clock | 64 MHz | 64 MHz - same | 64 MHz - same | 64 MHz - same | 48 MHz (-25%) | 40 MHz (-38%) |
| USB 2.0 Full-Speed | Yes (internal PHY) | Yes - same | Yes - same | Yes - same | Yes - same | No |
| Operating Temperature | -40C to +85C (industrial) | -40C to +85C - same | -40C to +125C (extended) | -40C to +85C - same | -40C to +85C - same | -40C to +85C - same |
| nanoWatt XLP Sleep Current | ~20 nA (typical) | ~20 nA - same | ~20 nA - same | ~20 nA - same | ~250 nA (worse) | No XLP (legacy) |
Key Differentiators
- nanoWatt XLP sleep current ~20 nA vs J-series ~250 nA (vs PIC18F26J53-I/SP)
- Industrial -40C to +85C grade with extended -40C to +125C option (vs PIC18F26K20-E/SP)
- 64 KB Flash with integrated USB and ECCP at 28-SPDIP price (vs PIC18F25K20-I/SP)
Design Notes
Estimated: At 64 MHz CPU and 3.3 V VDD, active current consumption is approximately 14 mA (per the PIC18FxxK20 datasheet electrical characteristic table). For battery-powered designs, duty-cycle aggressively: wake on interrupt, take ADC readings, transmit, then enter Sleep mode where nanoWatt XLP current drops to ~20 nA typical. Run Timer1 from a 32.768 kHz external crystal during Sleep for accurate periodic wake-ups. Always switch off unused peripherals with the PMD register to reduce quiescent current by an additional factor of two or more.
Estimated: Decouple VDD/AVDD pairs with 100 nF X7R ceramic placed within 3 mm of each pin pair, plus one 10 uF bulk capacitor shared per supply rail. Separate analog and digital ground planes if the board has an analog front-end; for the 28-SPDIP package with limited pins, a single ground pour with star-grounding at the MCU VSS pin is usually sufficient. Keep the MCLR pin's RC network (typically 10 kohm pull-up to VDD plus 100 nF to VSS) close to the pin to ensure clean reset behaviour; long MCLR traces pick up noise and cause spurious resets.
Do not exceed 3.6 V on VDD or 3.6 V on any I/O - the PIC18F26K20 silicon is rated for 1.8-3.6 V only. Level shifters are mandatory when interfacing 5 V peripherals; the I/O are NOT 5 V tolerant. Avoid the legacy 18F 'Configuration bits fuse blow' miscalibration - use MPLAB X to generate a clean .hex configuration. When using USB, ensure the 48 MHz USB clock is stable before connecting VBUS by polling the USB status register; otherwise the host may reject the enumeration.
Estimated: The 28-SPDIP package has longer lead inductance than the 28-QFN, so high-speed SPI at 8 MHz+ should keep traces short (under 50 mm). For long SPI cables, lower the clock to 1-2 MHz or add a series 33 ohm resistor at the SCK pin to dampen reflections. For USB 2.0 full-speed, route D+/D- as a 90-ohm differential pair with matched length; the SPDIP package has wider skew than QFN so test USB compliance carefully.
Compliance Information
Microchip parts are Pb-free and RoHS compliant per the datasheet ordering information section. AEC-Q100 is not stated; for automotive qualification choose the equivalent -Q-x grade family.
