PIC18F25K40-E/SS - 32KB Flash 8-bit MCU, 64MHz, SSOP-28 | Microchip
MPN: PIC18F25K40-E/SS ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $3.02 | $3.02 |
| 10 | $2.71 | $27.10 |
| 100 | $2.41 | $241.00 |
| 500 | $2.1 | $1,050.00 |
| 1,000 | $1.89 | $1,890.00 |
PIC18F25K40-E/SS Overview
A microcontroller (MCU) is a single-chip computer that integrates a CPU core, program and data memory, and programmable peripherals. PIC18 microcontrollers use an enhanced Harvard 8-bit RISC architecture with a modified instruction set that balances code density, deterministic interrupt latency, and C-compiler efficiency, and they sit within Microchip's broader taxonomy of 8-bit PIC microcontrollers, which feed into embedded controllers, microprocessors, and finally the broader category of semiconductors. Microchip's PIC18 "K40" family is positioned as a peripheral-rich, low-power upgrade path from earlier PIC18F "K20" and "K22" devices.
Key features of the PIC18F25K40-E/SS include 25 I/O pins, nine timers (three 16-bit timer/counters and six 8-bit), two 10-bit PWM channels, two analog comparators with selectable reference, and a peripheral pin-select (PPS) engine that maps digital peripherals to a wide range of pins. The ADC2 (10-bit) block features automatic accumulation, averaging, low-pass filtering, threshold comparison, and oversampling, allowing autonomous signal conditioning without CPU intervention. The CWG, HLT, WWDT, and CRC/SCAN modules are "Core Independent Peripherals" that offload motor control, fault handling, and memory-integrity tasks from the core.
Architecturally, the PIC18F25K40 uses a 16-bit instruction word and an 8-bit data path with a hardware multiplier, allowing efficient C compilation through MPLAB XC8 while preserving deterministic timing. The device supports on-chip debugging via Microchip's ICD (in-circuit debugger) interface and is fully supported by MPLAB X IDE, MCC code generator, and SEGGER J-Link emulators.
Typical applications include consumer appliances, building automation, low-power IoT sensor nodes, white goods and motor-control interfaces, USB-to-UART bridges (when paired with a USB-capable sibling), and industrial control boards that need deterministic 8-bit performance with strong peripheral integration.
When designing with the PIC18F25K40-E/SS, allocate ADC2 and CWG channels carefully because several analog and digital peripherals share pins via PPS. Verify the minimum operating voltage for the chosen oscillator mode (HF INTOSC supports down to 2.3 V) before committing to a 3.3 V-only rail.
This page synthesizes distributor pricing, drop-in same-package alternatives, and practical design notes not found in the manufacturer datasheet alone.
Drop-in alternatives for PIC18F25K40-E/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 PIC18F25K40-E/SS (same form factor and footprint) — differing in ADC, Core, Operating Temperature, Timers, Data SRAM.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PIC18F25K40-I/SS
✅ Drop-In✓ In Stock
$1.1 / Unit
View Datasheet →PIC18F25K40-E/SO
✅ Drop-In✓ In Stock
$1.32 / Unit
View Datasheet →PIC18F24K40-I/SS
✅ Drop-In ⚠️ Specs Unverified📋 Reference alternative (not in catalog)
PIC18F25K42-I/SS
✅ Drop-In✓ In Stock
$1.78 / Unit
View Datasheet →PIC18F25K22-I/SS
✅ Drop-In✓ In Stock
$1.92 / Unit
View Datasheet →PIC18F25K20-I/SS
✅ Drop-In ⚠️ Specs Unverified✓ In Stock
$1.92 / Unit
View Datasheet →PIC18F25K40-E/SS Maximum Ratings & Electrical Characteristics
| Product Family | PIC18F25K40 (PIC18 "K40" family) |
| Core | 8-bit PIC18 RISC, 16-bit instruction word |
| Maximum CPU Frequency | 64 MHz (16 MIPS) |
| Program Memory (Flash) | 32 KB (16K x 16) |
| Data SRAM | 2 KB |
| Data EEPROM | 256 B |
| Supply Voltage (VDD) | 3.0 V to 5.5 V |
| Operating Temperature Range (E suffix) | -40C to +125C |
| I/O Pins | 25 |
| ADC | 10-bit ADC2 with Computation, multiple channels |
| DAC | 5-bit DAC, 2 outputs |
| Comparators | 2 with selectable reference |
| Timers | 3 x 16-bit + 6 x 8-bit (9 timers total) |
| PWM Channels | 2 (10-bit) |
| CCP Modules | 2 (Capture/Compare/PWM) |
| Package | 28-pin SSOP (5.30 mm body) |
| Mounting Type | Surface Mount |
| RoHS Status | Compliant |
| Lead-Free | Yes |
PIC18F25K40-E/SS Pin Configuration
| Pin 1 | RA5/MCLR — Reset input / Master Clear (programming) / GPIO RA5 |
| Pin 2 | RA0 — GPIO RA0 / analog input |
| Pin 3 | RA1 — GPIO RA1 / analog input |
| Pin 4 | RA2 — GPIO RA2 / analog input |
| Pin 5 | RA3 — GPIO RA3 / analog input |
| Pin 6 | RA4 — GPIO RA4 / analog input |
| Pin 7 | RB4 — GPIO RB4 / analog input |
| Pin 8 | RB5 — GPIO RB5 / analog input |
| Pin 9 | RB6 — GPIO RB6 / ICD clock |
| Pin 10 | RB7 — GPIO RB7 / ICD data |
| Pin 11 | VSS — Ground reference |
| Pin 12 | VDD — Positive supply (3.0-5.5 V) |
| Pin 13 | RA6 — GPIO RA6 / analog input |
| Pin 14 | RA7 — GPIO RA7 / analog input |
| Pin 15 | RB0 — GPIO RB0 / analog input |
| Pin 16 | RB1 — GPIO RB1 / analog input |
| Pin 17 | RB2 — GPIO RB2 / analog input |
| Pin 18 | RB3 — GPIO RB3 / analog input |
| Pin 19 | RC0 — GPIO RC0 |
| Pin 20 | RC1 — GPIO RC1 |
| Pin 21 | RC2 — GPIO RC2 / PWM output |
| Pin 22 | RC3 — GPIO RC3 / SCL1 (I2C) |
| Pin 23 | RC4 — GPIO RC4 / SDA1 (I2C) |
| Pin 24 | RC5 — GPIO RC5 |
| Pin 25 | RC6 — GPIO RC6 / TX |
| Pin 26 | RC7 — GPIO RC7 / RX |
| Pin 27 | RD0 — GPIO RD0 |
| Pin 28 | RD1 — GPIO RD1 |
Typical Applications
PIC18F25K40-E/SS is suitable for 6 applications: Consumer Appliance Control, Building Automation Sensor Hubs, Industrial Control Boards, Low-Power IoT Edge Nodes, White Goods and Motor Interface, HMI / LED Display Controllers.
Consumer Appliance Control
The PIC18F25K40-E/SS suits consumer appliance controllers such as washing machines, dishwashers, and microwave ovens because its 32 KB Flash and 2 KB SRAM are sufficient for capacitive-touch UI, sensor fusion, and motor-control state machines, while the CWG and PWM peripherals drive TRIAC-controlled AC loads directly. The 10-bit ADC2 with Computation can digitize temperature, humidity, and level sensors autonomously, freeing the core to manage the user interface and safety logic. With -40C to +125C operating range and 5 V tolerance, the part tolerates the harsh electrical environment inside appliance cabinets.
Recommended
Building Automation Sensor Hubs
For building-automation sensor hubs and smart thermostats, the PIC18F25K40-E/SS combines XLP ultra-low-power sleep currents below 1 uA with rapid wake-up on interrupt-driven sensors, making it ideal for battery-powered wireless sensor nodes. The 10-bit ADC2 supports multi-channel analog sensor scanning for temperature, light, and CO2 analog front-ends, and the integrated 5-bit DAC can drive analog bias voltages for sensor signal conditioning. The 256 B EEPROM stores calibration data and node identity across power cycles without external memory.
Recommended
Industrial Control Boards
In PLC-style industrial control boards and process-control transmitters, the PIC18F25K40-E/SS provides deterministic 8-bit performance with the Windowed Watchdog Timer (WWDT) and CRC/SCAN hardware that ensures firmware integrity and safe operation in mission-critical loops. Its 25 I/O pins handle digital inputs, relay drivers, and PWM outputs, while the ADC2 with oversampling achieves effective >12-bit resolution for 4-20 mA loop measurements. The Extended -40C to +125C temperature grade supports outdoor panel installations.
Recommended
Low-Power IoT Edge Nodes
For battery-powered IoT edge nodes such as wireless environmental monitors and asset trackers, the PIC18F25K40-E/SS leverages XLP technology to achieve nanoWatt sleep currents, enabling multi-year battery life on a single coin cell. The 64 MHz core provides the throughput needed for on-sensor data compression and simple protocol stacks, while the peripheral pin-select (PPS) routes UART, SPI, and I2C to nearly any I/O pin, simplifying PCB layout under the tight SSOP-28 footprint. The CRC/SCAN module validates on-chip Flash at boot to detect firmware corruption.
Recommended
White Goods and Motor Interface
In washing machines, refrigerators, and HVAC damper controllers, the PIC18F25K40-E/SS integrates the CWG (Complementary Waveform Generator) that produces hardware dead-band-controlled complementary PWM outputs for driving half-bridge MOSFET gate drivers. This eliminates CPU overhead for motor commutation and synchronizes PWM to ADC2 sampling for sensorless BLDC control. The Hardware Limit Timer (HLT) provides hardware-based fault shutdown, ensuring the motor is disabled within microseconds of an over-current event.
Recommended
HMI / LED Display Controllers
For small graphical or segment LED HMI panels in coffee machines, lab instruments, and fitness equipment, the PIC18F25K40-E/SS multiplexes LED matrices and 7-segment displays using its 25 I/O pins and PWM channels, while the 2 KB SRAM provides ample frame-buffer memory for static and blinking displays. The MSSP peripheral supports SPI for high-speed LED-driver ICs, and the CWG can generate precise PWM dimming without CPU load. The PIC18F25K40-E/SS also handles debounced keypad inputs and UART communication with a host controller.
Recommended
Recommended Products Summary
Engineering reference data for PIC18F25K40-E/SS — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC18F25K40-I/SS | PIC18F25K40-E/SO | PIC18F24K40-I/SS | PIC18F25K42-I/SS | PIC18F25K22-I/SS | PIC18F25K20-I/SS |
|---|---|---|---|---|---|---|---|
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Package | SSOP-28 | SSOP-28 - same | SOIC-28 - pin-compatible (different land pattern) | SSOP-28 - same | SSOP-28 - same | SSOP-28 - same | SSOP-28 - same |
| Program Flash | 32 KB | 32 KB | 32 KB | 16 KB | 32 KB | 32 KB | 32 KB |
| SRAM | 2 KB | 2 KB | 2 KB | 1 KB | 2 KB | 2 KB | 1.5 KB |
| Maximum CPU Frequency | 64 MHz | 64 MHz | 64 MHz | 64 MHz | 64 MHz | 64 MHz | 64 MHz |
| Operating Temperature | -40C to +125C (E) | -40C to +85C (I) | -40C to +125C (E) | -40C to +85C (I) | -40C to +85C (I) | -40C to +85C (I) | -40C to +85C (I) |
| ADC2 Computation Engine | Yes (10-bit) | Yes | Yes | Yes | Yes | No (legacy 10-bit ADC) | No |
| CWG / HLT / WWDT | Yes (all 3) | Yes | Yes | Yes | Yes | No | No |
Key Differentiators
- Extended -40C to +125C operating temperature (vs PIC18F25K40-I/SS)
- Modern CIP (Core Independent Peripheral) set (vs PIC18F25K22-I/SS)
- 32 KB Flash plus 2 KB SRAM (vs PIC18F24K40-I/SS)
Design Notes
The PIC18F25K40-E/SS operates from 3.0 V to 5.5 V, but the HF-INTOSC supports down to 2.3 V with relaxed specifications. Place a 100 nF decoupling capacitor within 5 mm of VDD and a bulk 10 uF tantalum or ceramic on the same rail. Vcore pin (internally regulated) does not require external capacitance. Estimated: at 64 MHz active, IDD is typically 8-12 mA, so power dissipation at 5 V is approximately 50 mW.
Do not leave the MCLR/RA5 pin floating - either tie to VDD through a 10 kohm resistor for normal operation or use the internal MCLR configuration via CONFIG. The RB6/RB7 pins are shared with ICD (in-circuit debugger) clock/data; do not add low-impedance loads on these pins in production designs if you plan to debug with MPLAB ICD or PICkit. PPS (peripheral pin-select) must be unlocked before remapping; verify unlock sequence in firmware initialization.
SSOP-28 has 0.65 mm pitch - use 0.20 mm trace/space rules with 0.40 mm via diameter for fanout. Place a continuous ground pour on the top layer under the SSOP body for thermal dissipation and noise immunity. Keep ADC analog traces short and isolated from PWM/digital switching traces; add a ground guard ring around analog input pins. The exposed thermal pad is not present on this package, but 1 oz copper pour with thermal vias under the device is still recommended.
The 10-bit ADC2 with Computation supports oversampling and averaging; for effective resolution above 10 bits, set the ADC clock to Fosc/16 or slower and average 16-64 samples. Use a buffer (MCP6001 or similar) between high-impedance sensors and the ADC input to avoid charge-sharing errors. For I2C buses >100 kHz, add 4.7 kohm pull-ups on SCL1/SDA1 (RC3/RC4); for SPI at 8 MHz or higher, keep traces <50 mm with 33 ohm series damping resistors.
Compliance Information
RoHS and lead-free per Microchip product page. AEC-Q100 automotive qualification not formally listed for this part - Microchip PIC18 K40 family is generally industrial/consumer grade. For AEC-Q100 qualified PIC18, contact Microchip for the VAO suffix variants.
