PIC18F25K40-I/SP - 8-bit 64MHz MCU, 32KB Flash, 28-SPDIP
MPN: PIC18F25K40-I/SP ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $2.85 | $2.85 |
| 10 | $2.56 | $25.60 |
| 100 | $2.28 | $228.00 |
| 500 | $2.05 | $1,025.00 |
| 1,000 | $1.85 | $1,850.00 |
PIC18F25K40-I/SP Overview
A microcontroller (MCU) is a single-chip computer that integrates a CPU, RAM, non-volatile program memory (Flash/ROM), and I/O peripherals. Microcontrollers in the PIC18F family target the upper end of the 8-bit MCU market, blending C-compiler-optimized RISC architecture with rich peripheral integration, eXtreme Low Power (XLP) technology, and 5V support to suit a broad range of general-purpose embedded applications. The PIC18F25K40 belongs to the "high-performance" 8-bit MCU hierarchy: PIC18F > PIC18Fx K40 sub-family > Microchip 8-bit MCU > embedded controller > semiconductor.
Key features include 25 I/O pins, two 16-bit timers, a Windowed Watchdog Timer (WWDT) with a separate on-chip oscillator for safety-critical applications, an 8 MHz internal oscillator and 32 kHz secondary oscillator for low-power modes, plus eXtreme Low Power (XLP) sleep currents suitable for battery-powered designs. The ADC2 block supports hardware averaging, threshold comparisons, and automated scanning without CPU intervention.
Architecturally, the PIC18F25K40 uses the enhanced PIC18 Harvard architecture (C compiler optimized RISC with 16-bit instructions and 8-bit data) with an 8-deep hardware stack and interrupt priority levels. The internal oscillator supports PLL multiplication to 64 MHz, eliminating the need for an external crystal in cost-sensitive designs. CRC/Scan and Windowed WDT support IEC 60730 / Class B safety compliance for home appliance and industrial products.
Typical applications include appliance control (washing machines, microwave ovens, coffee makers), industrial sensor hubs, automotive body and lighting subsystems, IoT edge nodes, low-power metering, and consumer devices that benefit from CIP-driven peripheral operation. The wide 2.3V-5.5V operating range and XLP technology also support battery-backed and energy-harvesting designs.
Design consideration: When migrating code from PIC18F25K22 to PIC18F25K40, verify that the enhanced peripheral mapping (ADC2, CWG, HLT) is properly configured and that interrupt vector reassignments are applied. The PIC18F25K40 supports both "Legacy" and "Enhanced" mid-range compatibility modes for smoother migration paths from older families.
This page synthesizes distributor pricing, drop-in alternatives, and practical design notes not found in the manufacturer datasheet alone, helping procurement engineers and firmware developers evaluate the PIC18F25K40-I/SP for next-generation designs.
Drop-in alternatives for PIC18F25K40-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 PIC18F25K40-I/SP (same form factor and footprint) — differing in ADC, Package, Program Memory (Flash), Comparators, Family.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PIC18F25K40-E/SP
✅ Drop-In📋 Reference alternative (not in catalog)
PIC18F25K40-I/SO
✅ Drop-In📋 Reference alternative (not in catalog)
PIC18F25K40T-I/SO
✅ Drop-In✓ In Stock
$1.6 / Unit
View Datasheet →PIC18F45K40-I/P
✅ Drop-In📋 Reference alternative (not in catalog)
PIC18F24K40-I/SP
✅ Drop-In📋 Reference alternative (not in catalog)
PIC18F25K40-I/SP Maximum Ratings & Electrical Characteristics
| Core Architecture | PIC18 8-bit enhanced Harvard |
| Family | PIC18F "K40" high-performance |
| Program Memory (Flash) | 32 KB (16K x 16) |
| Data SRAM | 2 KB |
| Data EEPROM | 256 bytes |
| Maximum CPU Speed | 64 MHz |
| I/O Pins | 25 |
| ADC | 10-bit ADC2 with Computation |
| DAC | 5-bit DAC |
| Comparators | Yes |
| 16-bit Timers | 2 |
| PWM / CCP / CWG / HLT | Yes |
| WWDT (Windowed Watchdog) | Yes |
| SCAN / CRC Peripherals | Yes |
| Package | 28-SPDIP (Skinny Plastic DIP, through-hole) |
| RoHS Status | Compliant |
| Lead-Free | Yes |
| Temperature Range (I grade) | -40 C to +85 C industrial |
PIC18F25K40-I/SP Pin Configuration
| Pin 1 | MCLR/RE3 — Master Clear (reset) input or digital-only input on PORTE bit 3 |
| Pin 2 | RA0 — PORTA bit 0 / analog input |
| Pin 3 | RA1 — PORTA bit 1 / analog input |
| Pin 4 | RA2 — PORTA bit 2 / analog input |
| Pin 5 | RA3 — PORTA bit 3 / analog input |
| Pin 6 | RA4 — PORTA bit 4 / analog input |
| Pin 7 | RA5 — PORTA bit 5 / analog input |
| Pin 8 | VSS — Ground |
| Pin 9 | RA7 — PORTA bit 7 / analog input |
| Pin 10 | RA6 — PORTA bit 6 / analog input |
| Pin 11 | RC0 — PORTC bit 0 / analog input |
| Pin 12 | RC1 — PORTC bit 1 / analog input |
| Pin 13 | RC2 — PORTC bit 2 / analog input |
| Pin 14 | RC3 — PORTC bit 3 / analog input |
| Pin 15 | RC4 — PORTC bit 4 |
| Pin 16 | RC5 — PORTC bit 5 |
| Pin 17 | RC6 — PORTC bit 6 |
| Pin 18 | RC7 — PORTC bit 7 |
| Pin 19 | VSS — Ground |
| Pin 20 | VDD — Positive supply voltage |
| Pin 21 | RB0 — PORTB bit 0 / interrupt-on-change |
| Pin 22 | RB1 — PORTB bit 1 / interrupt-on-change |
| Pin 23 | RB2 — PORTB bit 2 / interrupt-on-change |
| Pin 24 | RB3 — PORTB bit 3 / interrupt-on-change |
| Pin 25 | RB4 — PORTB bit 4 / interrupt-on-change |
| Pin 26 | RB5 — PORTB bit 5 / interrupt-on-change |
| Pin 27 | RB6 — PORTB bit 6 / ICSclk |
| Pin 28 | RB7 — PORTB bit 7 / ICSdata |
Typical Applications
PIC18F25K40-I/SP is suitable for 6 applications: Home Appliance Control (Class B), Industrial Sensor Hub and Motor Control, Automotive Body and Lighting (Non-Safety), IoT Edge Node and Battery-Powered Device, Consumer Electronics User Interface, Medical Device Sub-System (Non-Implantable).
Home Appliance Control (Class B)
The PIC18F25K40-I/SP's on-chip Windowed Watchdog Timer (WWDT) with independent oscillator and hardware CRC/Scan module make it ideal for IEC 60730 Class B appliance designs. Its 32 KB Flash hosts Microchip's pre-validated Class B firmware library, while the ADC2 block performs motor current and temperature sensing without CPU intervention. Used in washing machine controllers, microwave ovens, and dishwasher user interfaces where functional safety is mandatory. The wide operating voltage window handles AC-rectified 5V rails directly.
Recommended
Industrial Sensor Hub and Motor Control
Industrial sensor hubs benefit from the PIC18F25K40-I/SP's 10-bit ADC2 with Computation (hardware averaging and threshold scanning), two 16-bit timers for PWM generation, and the Complementary Waveform Generator (CWG) for motor drive signals. The 64 MHz CPU frequency handles MODBUS ASCII/RTU stacks, sensor linearization, and PID control loops. Power-saving eXtreme Low Power (XLP) technology enables battery-backed 4-20 mA sensor transmitters. Operating temperature range and wide Vdd support harsh industrial environments.
Recommended
Automotive Body and Lighting (Non-Safety)
Body control modules and interior lighting drivers leverage the PIC18F25K40-I/SP's PWM, CCP, and CWG peripherals for LED dimming and H-bridge motor control. The 25 I/O pins and 5-bit DAC handle LIN-bus lighting nodes and dashboard indicator LEDs. Extended-temperature variants are available; for AEC-Q100 qualified safety-critical automotive, however, other Microchip families are required. The 28-SPDIP package suits through-hole development boards used in automotive engineering labs.
Recommended
IoT Edge Node and Battery-Powered Device
eXtreme Low Power (XLP) technology, sleep currents below 1 uA, and the PIC18F25K40-I/SP's 64 MHz high-performance mode make it a fit for IoT edge nodes that wake briefly, transmit over UART/SPI to an external radio, and return to sleep. The 32 KB Flash supports LoRaWAN / Sigfox reference stacks and on-chip TLS-friendly AES blocks via the CIP architecture. Designers can use the integrated 8 MHz internal oscillator, avoiding external XTALs in compact designs. Backup battery support leverages the wide 2.3V-5.5V range.
Recommended
Consumer Electronics User Interface
The PIC18F25K40-I/SP drives capacitive touch buttons, RGB LED status bars, and segment LCD/keypad interfaces on consumer devices such as coffee makers, smart thermostats, and remote controls. The CIP-driven ADC2 + CWG combination executes lighting transitions without CPU load, while the ADC computes ambient-light responses. The 28-SPDIP package aids rapid prototyping on breadboards during firmware development, with the SOIC variant targeted for volume production.
Recommended
Medical Device Sub-System (Non-Implantable)
Non-implantable medical sub-systems - infusion pump user panels, blood-pressure monitor MCUs, glucometer HMIs - use the PIC18F25K40-I/SP for its deterministic ADC2 scan, Windowed Watchdog, and Class B-capable firmware library. The 10-bit ADC2 supports accurate analog front-ends for sensor signal conditioning. Designers must still complete full IEC 60601 validation at the system level; Microchip provides collateral but the integrator owns compliance. The 28-SPDIP simplifies lab bring-up.
Recommended
Recommended Products Summary
Engineering reference data for PIC18F25K40-I/SP — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC18F25K40-E/SP | PIC18F25K40-I/SO | PIC18F25K40T-I/SO | PIC18F45K40-I/P | PIC18F24K40-I/SP |
|---|---|---|---|---|---|---|
| Package | 28-SPDIP | 28-SPDIP (same) | 28-SOIC (different footprint) | 28-SOIC T&R (different footprint) | 40-PDIP (different footprint) | 28-SPDIP (same) |
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Program Flash | 32 KB | 32 KB | 32 KB | 32 KB | 32 KB | 16 KB (-50%) |
| Data SRAM | 2 KB | 2 KB | 2 KB | 2 KB | 2 KB | 2 KB |
| EEPROM | 256 B | 256 B | 256 B | 256 B | 256 B | 256 B |
| Max CPU Speed | 64 MHz | 64 MHz | 64 MHz | 64 MHz | 64 MHz | 64 MHz |
| I/O Pins | 25 | 25 | 25 | 25 | 36 | 25 |
| Temperature Grade | I (-40C to +85C) | E (-40C to +125C) extended | I (-40C to +85C) | I (-40C to +85C) | I (-40C to +85C) | I (-40C to +85C) |
| ADC2 (10-bit + computation) | Yes | Yes | Yes | Yes | Yes | Yes |
Key Differentiators
- Core Independent Peripherals (CIP) drive motor and lighting control without CPU (vs PIC18F25K22-I/SP)
- Windowed WDT with independent oscillator for Class B safety (vs PIC18F24K40-I/SP)
- Through-hole 28-SPDIP package ideal for prototyping and breadboard bring-up (vs PIC18F25K40-I/SO)
Design Notes
The PIC18F25K40-I/SP supports 2.3V-5.5V operation with on-chip voltage regulator; place a 100 nF decoupling capacitor as close as possible to VDD pin (pin 20) and a bulk 10 uF on the main supply rail. For PIC18(L)F25K40 low-voltage variants the lower limit drops to 1.8V, but the same decoupling topology applies. Use a separate analog supply (AVDD) routed from VDD through a ferrite if ADC2 noise performance is critical.
The 28-SPDIP through-hole package gives 0.1" pin pitch for breadboard-style prototyping, but for production mount migrate to the PIC18F25K40-I/SO (28-SOIC) variant on the same schematic symbol library. Keep the MCLR/RE3 pull-up (typically 10 kohm) close to pin 1 and route the trace to the ICSP connector for in-circuit programming. Avoid routing high-current motor PWM signals adjacent to crystal/OSC pins.
When using the internal 8 MHz oscillator (HFINTOSC) with the 4x PLL to reach 64 MHz, expect higher jitter than an external crystal, which can impact UART timing at high baud rates. For UART communications >115200 baud over temperature, switch to an external HS crystal or use the internal oscillator's PLL with the failsafe clock monitor (FSEC + FCC). The ADC2 scan timing is derived from the system clock so a noisy PLL can degrade ADC accuracy.
Two common migration pitfalls when porting older PIC18F designs to the K40: (1) the configuration bits are now accessed via CONFIG registers (CONFIG1..CONFIG7) - failing to update the __config pragmas in the XC8 code yields a blank device; (2) the ADC is now ADC2 with computation registers ADCON0..ADCON3 plus ADPRE and ADACQ precharge and acquisition controls - using legacy ADCON1-only code silently produces incorrect conversions.
Compliance Information
RoHS compliant per Microchip product page. Not AEC-Q100 qualified - use automotive-grade PIC18F variants for AEC-Q100 needs. Halogen-free and lead-free per Microchip environmental compliance policy.
