PIC18F26K40-E/SO - 64KB Flash 8-bit MCU, 64MHz | Microchip
MPN: PIC18F26K40-E/SO ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $3.1 | $3.10 |
| 10 | $2.79 | $27.90 |
| 100 | $2.18 | $218.00 |
| 500 | $1.74 | $870.00 |
| 1,000 | $1.52 | $1,520.00 |
PIC18F26K40-E/SO Overview
What is a PIC18 K40 microcontroller? The PIC18 K40 family is Microchip's XLP (eXtreme Low Power) 8-bit PIC18 core device line that integrates Core Independent Peripherals (CIPs) such as CWG, WWDT, CRC/SCAN, 10-bit ADC2 with computation, 5-bit DAC, and configurable logic cells. Within the broader taxonomy: microcontroller (MCU) -> 8-bit MCU -> PIC18 core -> PIC18F K40 family -> low-power high-performance MCU -> embedded system on-chip. The K40 family continues Microchip's tradition of bringing CIPs to the PIC18 line for cost-optimized general-purpose applications.
Key features include 25 general-purpose I/O pins, two EUSART/MSSP serial interfaces, two 10-bit ADC modules with Computation Accelerator, a 5-bit DAC, multiple timer/counter modules, Complementary Waveform Generator (CWG), Zero-Cross Detect (ZCD), Windowed Watchdog Timer (WWDT), Hardware Limit Timer (HLT), and Peripheral Pin Select (PPS). The device offers up to 36 instruction set extensions for C-compiler code-density optimization and includes an integrated temperature indicator.
Typical applications include IoT edge nodes, sensor interface modules, battery-powered industrial controls, consumer appliances, motor control companion ICs (BLDC/Stepper), HVAC fan controllers, LED lighting control, and human-machine interface (HMI) subsystems. The wide 2.3V-5.5V supply range and XLP nanoWatt sleep currents below 50 nA make the device ideal for battery-powered designs that must operate for years on a single coin cell or 2xAA pack.
Design considerations include providing a 1uF decoupling capacitor on VDD, an external 0.1uF bypass on AVDD, and using the PPS module to remap peripheral signals to alternate pins. The Configuration Words must be set at the end of programming; always use ICD/ICSP header pins (PGC/PGD) for in-circuit debugging. For noisy industrial environments, enable the WWDT and use CRC/SCAN over Flash to detect firmware corruption.
The PIC18F26K40-E/SO combines large memory, rich CIP integration, and XLP nanoWatt technology in a 28-pin SOIC footprint that is pin-compatible with most PIC18F2xK22, PIC18F2xK40 and PIC18F2xK42 family variants. This page consolidates distributor pricing, drop-in alternatives and practical design notes beyond what appears in the manufacturer datasheet.
Drop-in alternatives for PIC18F26K40-E/SO — 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 PIC18F26K40-E/SO (same form factor and footprint) — differing in ADC, Package, Program Memory (Flash), Core Architecture, I/O Pins.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PIC18F26K40-I/SO
✅ Drop-In✓ In Stock
$1.41 / Unit
View Datasheet →PIC18F27K40-I/SO
✅ Drop-In ⚠️ Specs Unverified📋 Reference alternative (not in catalog)
PIC18F26K42-E/SO
✅ Drop-In ⚠️ Specs Unverified✓ In Stock
$2.54 / Unit
View Datasheet →PIC18F25K80-I/SO
✅ Drop-In✓ In Stock
$2.71 / Unit
View Datasheet →PIC18F26K22-I/SO
✅ Drop-In📋 Reference alternative (not in catalog)
PIC18F26K40-E/SO Maximum Ratings & Electrical Characteristics
| Core | PIC18 8-bit RISC |
| Program Memory (Flash) | 64 KB (32K x 16 words) |
| Data RAM | 4 KB |
| Data EEPROM | 256 bytes |
| Maximum CPU Clock | 64 MHz |
| Operating Voltage Range | 2.3 V to 5.5 V |
| I/O Pins | 25 |
| ADC | 10-bit ADC2 with Computation Accelerator |
| DAC | 5-bit DAC |
| Timers | 9 (multiple 8/16-bit) |
| Serial Interfaces | 2x EUSART/MSSP (SPI/I2C) |
| Package | 28-SOIC (7.50 mm width) |
| Mounting Type | Surface Mount |
| Operating Temperature | -40 C to +125 C (E = Extended) |
| RoHS Status | Compliant |
PIC18F26K40-E/SO Pin Configuration
| Pin 1 | RA0 — PORTA bit 0 / analog input / ICSPDAT alt |
| Pin 2 | RA1 — PORTA bit 1 / analog input |
| Pin 3 | RA2 — PORTA bit 2 / analog input |
| Pin 4 | RA3 — PORTA bit 3 / analog input / VREF+ |
| Pin 5 | RA4 — PORTA bit 4 / analog input |
| Pin 6 | RA5 — PORTA bit 5 / analog input |
| Pin 7 | RA6 — PORTA bit 6 / OSC2 / CLKOUT |
| Pin 8 | RA7 — PORTA bit 7 / OSC1 / CLKIN |
| Pin 9 | VSS — Ground reference |
| Pin 10 | RB7 — PORTB bit 7 / ICSPCLK / PGC |
| Pin 11 | RB6 — PORTB bit 6 / ICSPDAT / PGD |
| Pin 12 | RB5 — PORTB bit 5 / analog input |
| Pin 13 | RB4 — PORTB bit 4 / analog input |
| Pin 14 | RB3 — PORTB bit 3 / analog input |
| Pin 15 | RB2 — PORTB bit 2 / analog input |
| Pin 16 | RB1 — PORTB bit 1 / analog input |
| Pin 17 | RB0 — PORTB bit 0 / analog input / interrupt-on-change |
| Pin 18 | VSS — Optional secondary ground |
| Pin 19 | VDD — Primary 2.3V-5.5V supply |
| Pin 20 | AVDD — Analog supply (tie to VDD) |
| Pin 21 | AVSS — Analog ground (tie to VSS) |
| Pin 22 | RC7 — PORTC bit 7 / RX/DT |
| Pin 23 | RC6 — PORTC bit 6 / TX/CK |
| Pin 24 | RC5 — PORTC bit 5 |
| Pin 25 | RC4 — PORTC bit 4 |
| Pin 26 | RC3 — PORTC bit 3 / SCL (MSSP) |
| Pin 27 | RC2 — PORTC bit 2 / SDA (MSSP) |
| Pin 28 | RC1 — PORTC bit 1 / CCP2 |
| Pin 29 | RC0 — PORTC bit 0 |
| Pin 30 | RE3 — PORTE bit 3 / MCLR / reset input |
| Pin 31 | NC — Not connected (28-pin SOIC pin count variant) |
| Pin 32 | NC — Not connected (28-pin SOIC pin count variant) |
Typical Applications
PIC18F26K40-E/SO is suitable for 7 applications: Battery-Powered IoT Edge Nodes, Industrial Sensor Interface Modules, Automotive Body Electronics, Consumer Appliance Control Boards, LED Lighting and Color-Mixing Controllers, Human-Machine Interface (HMI) Subsystems, Motor Control Companion MCU.
Battery-Powered IoT Edge Nodes
The PIC18F26K40-E/SO fits IoT edge node designs because its nanoWatt XLP sleep current below 50 nA and 64KB Flash leave ample headroom for BLE/Zigbee protocol stacks. The 5V-tolerant GPIO simplifies connection to coin-cell-boosted rails, and 25 GPIO is sufficient to drive sensors, user buttons and a status LED. Compared with running the same workload on a 32-bit Cortex-M0+ at similar sleep currents, the K40's deterministic 8-bit execution and single-cycle 16-bit ALU often yield lower active energy per measurement. PPS lets the designer route EUSART/MSSP to any pin, eliminating PCB re-spins when changing radio modules. Use it for thermostat sensors, smart agriculture probes, water-meter telemetry and asset trackers.
Recommended
Industrial Sensor Interface Modules
The PIC18F26K40-E/SO's 10-bit ADC2 with Computation Accelerator and on-chip 5-bit DAC make it a strong fit for 4-20 mA analog sensor conditioning boards. The CIP-driven CRC/SCAN and WWDT simplify IEC 61508 SIL-2 firmware integrity monitoring. 25 GPIO lines drive opto-isolated inputs, relay outputs and a Modbus RTU link via EUSART. The -40C to +125C extended temperature range covers outdoor cabinet installations. By integrating analog filtering and threshold detection in hardware CLC blocks, the K40 reduces bill-of-materials versus a discrete op-amp + MCU implementation. Use it for pressure transducers, flow meters and vibration sensor heads.
Recommended
Automotive Body Electronics
The PIC18F26K40-E/SO is widely deployed in non-safety automotive body electronics such as interior lighting controllers, seat-memory modules and HVAC flap drivers. Its 2.3V-5.5V supply tolerates load-dump transients when paired with a 5V regulator, and 25 GPIO can drive multiple LIN-style actuator drivers. CWG (Complementary Waveform Generator) hardware produces dead-band-protected PWM for DC motor direction control without CPU intervention. While the E temperature grade extends to +125C, true AEC-Q100 automotive qualification requires the -VAO suffix variant. For window lifters, seat heaters and tail-light LIN slaves, the K40 in 28-SOIC remains a cost-optimized solution.
Recommended
Consumer Appliance Control Boards
The PIC18F26K40-E/SO targets consumer appliance control boards such as washing-machine UI panels, induction-cooktop keypads, microwave displays and refrigerator thermostats. The 5V-tolerant digital I/O directly drives LED segment displays, while EUSART/MSSP interfaces touch controllers and seven-segment drivers. With 64KB Flash the K40 holds full state-machine logic plus an IEC 60730 safety library (Class B) including watchdog, clock monitor and Flash CRC. nanoWatt sleep reduces standby consumption below EU eco-design standby limits. The 28-SOIC footprint is mechanically robust for hand-soldered prototypes and high-volume wave soldering alike.
Recommended
LED Lighting and Color-Mixing Controllers
The PIC18F26K40-E/SO drives multi-channel LED lighting fixtures using its 16-bit PWM and Complementary Waveform Generator for high-resolution dimming. The CWG hardware generates non-overlapping complementary outputs for half-bridge LED driver stages, eliminating shoot-through without CPU overhead. The 5-bit on-chip DAC plus external op-amps form an analog constant-current reference for low-cost white-LED strings. For RGBW color-mixing designs, the K40's PPS allows remapping PWM channels to any pin so PCB layout can route signals cleanly. Use it for architectural dimmers, stage lighting and horticulture grow-light fixtures.
Recommended
Human-Machine Interface (HMI) Subsystems
The PIC18F26K40-E/SO serves as an HMI coprocessor in products with graphical TFT or segment LCDs, handling key-scanning, rotary encoder input and LED status while the main application processor handles graphics. 25 GPIO comfortably drives a 4x4 matrix keypad plus encoder, with UART/SPI back to the host. The on-chip CLC blocks debounce switch inputs in hardware, freeing the CPU from interrupt storms. nanoWatt XLP sleep below 50 nA preserves battery life on portable HMIs. Typical deployments include industrial control panels, vending machines and medical device front panels.
Recommended
Motor Control Companion MCU
The PIC18F26K40-E/SO is used as a companion MCU next to a dedicated motor-control DSPIC, handling communication (CAN, LIN, UART), safety monitoring and housekeeping PWM. Its WWDT and CRC/SCAN provide a hardware integrity check on shared SPI buses. The K40's low latency interrupt response (50 ns typical) makes it ideal for fast shutdown paths. 25 GPIO accept end-of-travel limit switches and encoder feedback while driving low-side relays. For BLDC, stepper or brushed DC systems, the K40 in 28-SOIC provides a cost-optimized supervisor for the power stage.
Recommended
Recommended Products Summary
Engineering reference data for PIC18F26K40-E/SO — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC18F26K40-I/SO | PIC18F27K40-I/SO | PIC18F26K42-E/SO | PIC18F25K80-I/SO | PIC18F26K22-I/SO |
|---|---|---|---|---|---|---|
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Package | 28-SOIC (7.50 mm) | 28-SOIC (7.50 mm) - same | 28-SOIC (7.50 mm) - same | 28-SOIC (7.50 mm) - same | 28-SOIC (7.50 mm) - same | 28-SOIC (7.50 mm) - same |
| Flash | 64 KB | 64 KB | 128 KB (+100%) | 64 KB | 32 KB (-50%) | 32 KB (-50%) |
| RAM | 4 KB | 4 KB | 4 KB | 4 KB | 2 KB (-50%) | 1 KB (-75%) |
| EEPROM | 256 B | 256 B | 256 B | 256 B | 1 KB (+300%) | 256 B |
| Max CPU Clock | 64 MHz | 64 MHz | 64 MHz | 64 MHz | 64 MHz | 64 MHz |
| 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 5.5 V (wider) | 1.8 V to 5.5 V (wider) |
| Temperature Range | -40 C to +125 C (E) | -40 C to +85 C (I) | -40 C to +85 C (I) | -40 C to +125 C (E) | -40 C to +85 C (I) | -40 C to +125 C (E) |
| I/O Pins | 25 | 25 | 25 | 25 | 24 (-1) | 24 (-1) |
Key Differentiators
- Extended temperature range to +125C versus -85C industrial grade (vs PIC18F26K40-I/SO)
- Core Independent Peripherals integrated versus older K22 generation (vs PIC18F26K22-I/SO)
- Newer K42 family upgrade path with DMA and faster ADC (vs PIC18F26K42-E/SO)
- More Flash and RAM than the K80 in the same footprint (vs PIC18F25K80-I/SO)
Design Notes
Place a 1uF ceramic decoupling capacitor (X7R, 10V rating) as close as possible to the VDD pin (pin 20 on 28-SOIC). Add a 0.1uF ceramic bypass to the AVDD pin and tie AVDD to VDD via a ferrite bead for noise-sensitive analog measurements. Estimated: for a 64MHz clock the K40 draws approximately 11 mA active, so the bulk supply trace should be at least 10 mil wide on the top copper pour.
Route the ICSP clock (RB6/ICSPCLK, pin 11) and ICSP data (RB7/ICSPDAT, pin 10) signals to a 2x3 100-mil ICSP header without stubs longer than 25mm. Keep crystal traces (RA6/OSC2 and RA7/OSC1) symmetric and within 5mm of the IC. Place the MCLR pull-up resistor (typically 10k to VDD) within 5mm of pin 1 (RE3/MCLR). All unused I/O pins should be configured as outputs and tied to ground for lowest EMI signature.
Do not enable PPS remapping before unlocking the PPSLOCK register sequence; failure to do so locks the device from further programming until a reset occurs. Always set Configuration Words at the end of the programming flow, never mid-flow, so the ICD debugger retains visibility. When migrating firmware from PIC18F26K22 to PIC18F26K40, remember that PPS registers replace fixed peripheral pin assignments; remap each EUSART/MSSP and CCP route explicitly in the new code.
Estimated: the I2C MSSP bus on RC3/RC2 (pins 26/27) is not 5V-tolerant when configured as I2C; if a 5V pull-up is used, add an external level translator or clamp diode. For long I2C bus runs above 50mm, reduce the pull-up current to 1mA by using 4.7k resistors and lower the I2C baud to 100 kHz to avoid ringing. Enable the slew-rate control bits in the SSPxCON register when bus capacitance exceeds 200 pF.
Compliance Information
RoHS and REACH compliant per Microchip product page 2026-09-27. Standard PIC18F26K40-E/SO is not AEC-Q100 qualified; for AEC-Q100 automotive use choose -VAO suffix variant. Lead-free and halogen-free per Microchip environmental data sheet.
