PIC18LF25K40T-I/SO - 32KB Flash XLP MCU 28-SOIC | Microchip
MPN: PIC18LF25K40T-I/SO ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $2.45 | $2.45 |
| 10 | $2.2 | $22.00 |
| 100 | $1.95 | $195.00 |
| 500 | $1.75 | $875.00 |
| 1,000 | $1.55 | $1,550.00 |
PIC18LF25K40T-I/SO Overview
A microcontroller (MCU) is a single-chip computer that integrates a CPU core, program and data memory, peripherals, and I/O on one die. PIC18 devices sit in Microchip's 8-bit 'PIC' family hierarchy: PIC18F -> PIC18 'LF' (low-voltage) -> PIC18 K-series -> 28-pin '25K40' variant. They occupy the 'general purpose, ultra-low-power' tier of the embedded market, bridging between legacy 8-bit PIC16 designs and the higher-pin-count PIC18F 'K40/K42/K80' series.
Key features include 32 KB self-programmable Flash, 2 KB SRAM, 256 B data EEPROM, an internal 64 MHz oscillator, four 16-bit timers, two CCP modules, two UART, two SPI, two I2C, an 11-channel 10-bit ADC with computation, a 5-bit DAC, and nanoWatt XLP sleep currents below 50 nA typical. The 'T' suffix denotes Tape & Reel; the 'SO' suffix denotes the 28-pin 0.300" SOIC package; 'I' is the -40C to +85C industrial grade.
Technical depth: the K-series uses a 16-bit instruction word PIC18 core with hardware multiply, a 31-level stack, and PPS that lets each peripheral be mapped to multiple physical pins. The 10-bit ADC with computation supports hardware averaging and threshold comparison, offloading DSP-like tasks from the CPU. The integrated CWG (Complementary Waveform Generator) drives MOSFET half-bridges without software timing.
Typical applications include LoRa/sensor node edge controllers, battery-powered IoT nodes, home appliance user interfaces, motor control companion MCUs, USB-CDC sensor bridges (with PIC18F version for 5V), and industrial sensor conditioning. The wide 1.8V-3.6V range suits 2xAA/coin-cell powered designs where the 'LF' variant offers the lowest active current draw.
Design consideration: select the 'F' variant (PIC18F25K40) for 5V-tolerant operation and the 'LF' variant (this part) for low-voltage battery operation; verify each peripheral's remapping on PPS before committing pin assignments. The 28-SOIC footprint is pin-compatible across the PIC18F/LF25K40 family and PIC18F/LF25K22, easing migration.
Drop-in alternatives for PIC18LF25K40T-I/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 PIC18LF25K40T-I/SO (same form factor and footprint) — differing in ADC, Package, Program Memory (Flash), DAC, Core Architecture.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PIC18LF25K40-I/SO
✅ Drop-In✓ In Stock
$1.65 / Unit
View Datasheet →PIC18LF25K40T-E/SO
✅ Drop-In📋 Reference alternative (not in catalog)
PIC18LF24K40T-I/SO
✅ Drop-In✓ In Stock
$1.86 / Unit
View Datasheet →PIC18F25K40T-I/SO
✅ Drop-In✓ In Stock
$1.6 / Unit
View Datasheet →PIC18F25K22-I/SO
✅ Drop-In✓ In Stock
$1.78 / Unit
View Datasheet →PIC18LF25K40T-I/SO Maximum Ratings & Electrical Characteristics
| Core | PIC18 8-bit enhanced mid-range |
| Program Memory (Flash) | 32 KB (16K x 16 words) |
| Data SRAM | 2 KB |
| Data EEPROM | 256 B |
| Maximum CPU Speed | 64 MHz (16 MIPS) |
| Operating Voltage Range | 1.8 V to 3.6 V (LF variant) |
| I/O Pins | 25 |
| ADC | 10-bit, up to 11 channels, with computation |
| DAC | 5-bit |
| UART | 2 |
| SPI | 2 |
| I2C | 2 (SMBus/PMBus compatible) |
| Timers (16-bit) | 4 |
| CCP Modules | 2 |
| Complementary Waveform Generator (CWG) | Yes |
| Windowed Watchdog Timer (WWDT) | Yes |
| CRC/Memory Scan | Yes |
| Hardware CVD | Yes |
| Zero-Cross Detect | Yes |
| Peripheral Pin Select (PPS) | Yes |
| nanoWatt XLP Sleep Current | < 50 nA typical |
| Package | 28-SOIC (0.295" / 7.50 mm body, SO) |
| Operating Temperature | -40 C to +85 C (Industrial, 'I' suffix) |
| Mounting Type | Surface Mount |
| Packaging | Tape & Reel ('T' suffix) |
| RoHS Status | Compliant |
PIC18LF25K40T-I/SO Pin Configuration
| Pin 1 | RA5 — Bidirectional I/O, analog input, PPS-capable |
| Pin 2 | RA4 — Bidirectional I/O, analog input |
| Pin 3 | RA3 — Bidirectional I/O, analog input |
| Pin 4 | RA2 — Bidirectional I/O, analog input |
| Pin 5 | RA1 — Bidirectional I/O, analog input |
| Pin 6 | RA0 — Bidirectional I/O, analog input |
| Pin 7 | VSS — Ground reference |
| Pin 8 | RA7 — Bidirectional I/O, OSC1 |
| Pin 9 | RA6 — Bidirectional I/O, OSC2 |
| Pin 10 | RC0 — Bidirectional I/O, SOSCO |
| Pin 11 | RC1 — Bidirectional I/O, SOSCI |
| Pin 12 | RC2 — Bidirectional I/O, analog input |
| Pin 13 | RC3 — Bidirectional I/O, analog input, SCL |
| Pin 14 | RC4 — Bidirectional I/O, analog input, SDA |
| Pin 15 | RC5 — Bidirectional I/O, analog input |
| Pin 16 | RC6 — Bidirectional I/O, TX/CK |
| Pin 17 | RC7 — Bidirectional I/O, RX/DT |
| Pin 18 | VSS — Ground reference |
| Pin 19 | VDD — Positive supply (1.8V-3.6V for LF) |
| Pin 20 | RB0 — Bidirectional I/O, analog input, INT0 |
| Pin 21 | RB1 — Bidirectional I/O, analog input, INT1 |
| Pin 22 | RB2 — Bidirectional I/O, analog input |
| Pin 23 | RB3 — Bidirectional I/O, analog input |
| Pin 24 | RB4 — Bidirectional I/O, analog input |
| Pin 25 | RB5 — Bidirectional I/O, analog input |
| Pin 26 | RB6 — Bidirectional I/O, ICSPCLK |
| Pin 27 | RB7 — Bidirectional I/O, ICSPDAT |
| Pin 28 | RE3 — Input-only, Master Clear (MCLR) |
Typical Applications
PIC18LF25K40T-I/SO is suitable for 7 applications: Battery-Powered IoT Sensor Node, Home Appliance User Interface, Motor Control Companion MCU, USB-CDC Sensor Bridge, Industrial Sensor Conditioning, Wearables and Fitness Devices, Smart Home Edge Controller.
Battery-Powered IoT Sensor Node
The PIC18LF25K40T-I/SO is ideal for battery-powered IoT sensor nodes because its 'LF' variant operates from 1.8V to 3.6V with nanoWatt XLP sleep currents below 50 nA typical, enabling multi-year battery life from a 2xAA or CR2032 coin cell. The 32 KB Flash and 2 KB SRAM comfortably run sensor-fusion code, and the 10-bit ADC with computation offloads averaging from the CPU. The PPS lets the LoRa/SPI/sub-GHz module share pins with the I2C sensor, reducing board complexity. Compared to a PIC18F25K22, this part adds the K-series PPS flexibility and modern XLP sleep modes that extend runtime by 30-50% in duty-cycled sensor designs.
Recommended
Home Appliance User Interface
The PIC18LF25K40T-I/SO fits washing-machine, dishwasher, and microwave user-interface boards thanks to its 25 I/O pins that drive 7-segment displays, keypads, and LED indicators while Peripheral Pin Select (PPS) lets the same firmware re-target different pin assignments across product variants. The 32 KB Flash stores UI state machines and the 10-bit ADC with computation reads potentiometers and thermistor inputs. Operating from 1.8V to 3.6V reduces heat and supports low-cost LDO rails. Compared to the older PIC18F25K22, the K40's nanoWatt XLP standby lets an always-on UI draw under 1 mA average, passing IEC 62301 standby energy standards.
Recommended
Motor Control Companion MCU
The PIC18LF25K40T-I/SO serves as a companion MCU in motor-control subsystems where its Complementary Waveform Generator (CWG) drives MOSFET half-bridges with hardware dead-band timing, offloading the CPU from real-time switching tasks. The 16 MIPS performance handles FOC loop scheduling at low RPM while the 10-bit ADC with computation samples phase currents. The 32 KB Flash accommodates sensorless start-up routines. The 'LF' low-voltage rail matches a 3.3V gate-driver supply. Compared to the PIC18F25K22, the K40 adds CWG peripheral not present on the K22, eliminating a timer for the dead-band generator.
Recommended
USB-CDC Sensor Bridge
The PIC18LF25K40T-I/SO implements USB-CDC device-class sensor bridges using the UART-to-USB firmware stacks provided by Microchip's application libraries, with 32 KB Flash holding CDC class driver plus application code. The two UART modules expose RS-232/RS-485 sensors while PPS lets designers route UART pins around PCB layout constraints. Operating from 1.8V to 3.6V it pairs with 3.3V USB voltage regulators without level shifters. Compared to the PIC18F25K40 (5V F-variant), this 'LF' part is preferred for bus-powered designs where 5V supply is unavailable.
Recommended
Industrial Sensor Conditioning
The PIC18LF25K40T-I/SO integrates 11-channel 10-bit ADC with computation, Hardware CVD (Capacitive Voltage Divider), and Zero-Cross Detect, making it ideal for industrial 4-20 mA loop signal conditioning and capacitive touch interfaces. The 32 KB Flash stores calibration tables while the 2 KB SRAM buffers ADC sample averaging. The industrial -40C to +85C temperature range suits factory-floor enclosures. The 28-SOIC footprint survives wave-solder and selective-solder assembly. Compared to the PIC18F25K22, the K40's Hardware CVD module replaces external capacitor-discharge analog front-ends, reducing BOM by 2-3 components.
Recommended
Wearables and Fitness Devices
The PIC18LF25K40T-I/SO powers wearable fitness devices where nanoWatt XLP sleep currents below 50 nA typical allow 24/7 heart-rate monitoring on a CR2032 cell lasting over a year. The 'LF' 1.8V-3.6V operation matches coin-cell chemistry directly without a boost converter. The CWG drives haptic feedback motors while the 10-bit ADC reads pulse-oximeter photodiode signals. The 32 KB Flash stores pedometer algorithms and BLE-stack thunks. The 28-SOIC package is preferred over QFN for hand-repairable wearables. Compared to an 8-bit PIC16, the K40's PPS allows UART and SPI to share pins, simplifying the BLE module layout.
Recommended
Smart Home Edge Controller
The PIC18LF25K40T-I/SO serves as an edge controller in smart-home gateways, reading I2C sensors (temperature, humidity, motion) and forwarding via UART/SPI to a host SoC. The 32 KB Flash accommodates device drivers for multiple sensor ICs while PPS lets a single PCB layout accept different sensor combinations. The 64 MHz CPU decodes BLE/Zigbee packet headers for gateway pre-processing. Operating from 1.8V-3.6V matches 2xAA or USB-power rails. The 25 I/O pins drive status LEDs and button inputs. Compared to a PIC18F25K22, the K40's nanoWatt XLP standby lets battery-backed smart-home sensors pass 10-year battery-life targets.
Recommended
Recommended Products Summary
Engineering reference data for PIC18LF25K40T-I/SO — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC18LF25K40-I/SO | PIC18LF25K40T-E/SO | PIC18LF24K40T-I/SO | PIC18F25K40T-I/SO | PIC18F25K22-I/SO |
|---|---|---|---|---|---|---|
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Package | 28-SOIC (SO) | 28-SOIC (SO) - same | 28-SOIC (SO) - same | 28-SOIC (SO) - same | 28-SOIC (SO) - same | 28-SOIC (SO) - same |
| Program Memory | 32 KB | 32 KB | 32 KB | 16 KB | 32 KB | 32 KB |
| Data SRAM | 2 KB | 2 KB | 2 KB | 1 KB | 2 KB | 2 KB |
| Data EEPROM | 256 B | 256 B | 256 B | 256 B | 256 B | 256 B |
| Operating Voltage | 1.8 V to 3.6 V | 1.8 V to 3.6 V | 1.8 V to 3.6 V | 1.8 V to 3.6 V | 2.3 V to 5.5 V | 2.3 V to 5.5 V |
| Maximum CPU Speed | 64 MHz (16 MIPS) | 64 MHz | 64 MHz | 64 MHz | 64 MHz | 64 MHz |
| Peripheral Pin Select (PPS) | Yes | Yes | Yes | Yes | Yes | No |
| nanoWatt XLP Sleep | Yes (<50 nA typical) | Yes | Yes | Yes | Yes | No |
| Operating Temperature | -40 C to +85 C (Industrial) | -40 C to +85 C | -40 C to +125 C (Extended) | -40 C to +85 C | -40 C to +85 C | -40 C to +85 C |
| Unit Price (qty 1, USD) | 2.45 | 2.40 | 2.85 | 2.20 | 2.55 | 2.75 |
Key Differentiators
- Low-voltage LF variant for 1.8V-3.6V battery operation (vs PIC18F25K40T-I/SO)
- Modern Peripheral Pin Select (PPS) for flexible peripheral routing (vs PIC18F25K22-I/SO)
- Full 32 KB Flash with nanoWatt XLP sleep < 50 nA (vs PIC18LF24K40T-I/SO)
Design Notes
For battery-powered designs, leverage nanoWatt XLP modes: configure the MCU to enter Sleep mode between sensor reads and use the Watchdog Timer (WWDT) for periodic wake. Estimated sleep current is below 50 nA typical. Add a 100 nF decoupling capacitor on VDD close to the IC and a 10 uF bulk capacitor on the supply rail. Connect unused I/O to VDD or VSS to prevent floating-input leakage; floating CMOS inputs can draw several microamps each.
Place VDD and VSS decoupling capacitors within 2 mm of their respective pins; the 28-SOIC package has VDD on pin 19 and VSS on pins 7 and 18. Use a 4-layer PCB with a dedicated ground plane for clean ADC readings; place the analog traces away from switching traces and bypass the AVdd with an LC filter when driving ADC. Use wide 0.2 mm power traces. Route the ICSP signals (RB6/ICSPCLK and RB7/ICSPDAT) on the PCB to enable in-circuit programming without removing the chip from the board.
Use Peripheral Pin Select (PPS) to remap peripherals to non-default pins, which simplifies PCB routing when crossing signals between analog and digital sections. Route the high-speed oscillator traces (RA6/OSC2, RA7/OSC1) short and surrounded by ground. Keep crystal traces within 5 mm of the IC; use load capacitors per the crystal manufacturer's specification. Ensure MCLR pin (RE3 on pin 28) has a 10 kohm pull-up to VDD; never leave it floating, or the device may randomly reset.
Do not use PIC18LF code written for PIC18F variants without verifying the operating voltage range; PIC18LF (1.8V-3.6V) cannot be clocked to 64 MHz below 3.0V per the datasheet DC characteristics. Ensure the configuration bits (CONFIG1) are set to the correct oscillator and watchdog settings before programming - a misconfigured watchdog will lock the device into endless reset. Verify VDD ramp time is under the datasheet maximum to avoid POR issues. The 'LF' low-voltage variant does NOT support 5V input on any pin; using it in a 5V system will damage the MCU.
Compliance Information
RoHS and REACH compliance per Microchip product page. AEC-Q100 qualification is not applicable for industrial-grade ('I') MCUs - choose PIC18LF25K40T-E/SO (extended temperature) for harsher environments.
