PIC18F25K22-I/SO - 8-Bit 64MHz 32KB Flash MCU | Microchip
MPN: PIC18F25K22-I/SO ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $2.62 | $2.62 |
| 10 | $2.42 | $24.20 |
| 100 | $2.18 | $218.00 |
| 500 | $1.96 | $980.00 |
| 1,000 | $1.78 | $1,780.00 |
PIC18F25K22-I/SO Overview
A microcontroller (MCU) is a single-chip computer that integrates a CPU core, program and data memory, peripherals, and I/O into one package. The PIC18F family sits within Microchip's 8-bit PIC architecture hierarchy (PIC10/12/14/16 -> PIC18 -> 16-bit dsPIC/PIC24 -> 32-bit PIC32) and is widely adopted in cost-sensitive, low-power embedded designs where deterministic interrupt response and ultra-low standby current matter more than raw compute throughput. The K22 sub-family adds nanoWatt XLP sleep modes that drop quiescent current below 100 nA in deep sleep, making it well suited to battery-powered sensor nodes.
Key features include 64MHz internal oscillator operation, 1.8V-5.5V wide VDD range (specific VDD min depends on configuration), 10-bit ADC with up to 19 channels, multiple 16-bit timers, two Enhanced USART modules supporting LIN and IrDA, two MSSP ports configurable for SPI or I2C master/slave, an enhanced PWM module with up to 7 outputs, and a charge time measurement unit (CTMU) for capacitive touch. The device supports in-circuit serial programming (ICSP) and in-circuit debug (ICD) via Microchip's MPLAB ecosystem, including MPLAB X IDE and XC8 compiler.
Typical applications include consumer appliances, IoT sensor nodes, low-power remote controls, motor control subsystems, USB-to-UART bridges (paired with internal USART + external USB controller), industrial control panels, and battery-backed metering. The wide voltage range and ultra-low sleep current make it a strong choice for energy harvesting or multi-year battery-life products.
When designing with this part, ensure decoupling caps (100 nF plus 1-10 uF bulk) sit within a few millimeters of VDD/AVDD pins, route MCLR through a proper reset network, and follow Microchip's recommended ICSP connector pinout if you intend field upgrades. For lowest sleep current, disable unused peripherals, switch to the 31 kHz LFINTOSC, and gate clocks via the SLEEP/IDLE modes rather than polling loops.
This page synthesizes distributor pricing, drop-in pin-compatible alternatives, and practical design notes not found in the manufacturer datasheet alone.
Drop-in alternatives for PIC18F25K22-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 PIC18F25K22-I/SO (same form factor and footprint) — differing in Package, ADC, Core, Operating Temperature, Program Memory (Flash).
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PIC18F25K22-E/SO
✅ Drop-In ⚠️ Specs Unverified✓ In Stock
$2.96 / Unit
View Datasheet →PIC18F26K22-I/SO
✅ Drop-In📋 Reference alternative (not in catalog)
PIC18F24K22-I/SO
✅ Drop-In ⚠️ Specs Unverified📋 Reference alternative (not in catalog)
PIC18F25K20-I/SO
✅ Drop-In ⚠️ Specs Unverified✓ In Stock
$2.55 / Unit
View Datasheet →PIC18F25Q10-I/SO
✅ Drop-In📋 Reference alternative (not in catalog)
PIC18F25K22-I/SO Maximum Ratings & Electrical Characteristics
| Core Architecture | PIC18 (8-bit) |
| Maximum CPU Clock | 64 MHz |
| Program Memory (Flash) | 32 KB (16K x 16 words) |
| RAM | 1536 bytes |
| EEPROM | 256 bytes |
| Supply Voltage (VDD) | 1.8 V to 5.5 V (range varies by configuration) |
| I/O Pins | 25 |
| ADC | 10-bit, up to 19 channels |
| Timers | Multiple 8-bit and 16-bit |
| Communication | 2x Enhanced USART (LIN/IrDA), 2x MSSP (SPI/I2C) |
| PWM Outputs | Up to 7 |
| Operating Temperature (Industrial) | -40 C to +85 C |
| Package | 28-pin SOIC wide (SO) |
| Mounting Type | Surface Mount |
| Low-Power Technology | nanoWatt XLP |
| RoHS Status | Compliant |
PIC18F25K22-I/SO Pin Configuration
| Pin 1 | MCLR/VPP/RE3 — Master Clear (Reset) input or programming voltage; also general I/O RE3 |
| Pin 2 | RA0/AN0/C12IN0-/ULPWU — PORTA bit 0; analog input 0; comparator input; ultra-low-power wake-up |
| Pin 3 | RA1/AN1/C12IN1-/CTDIN — PORTA bit 1; analog input 1; comparator input; CTMU digital input |
| Pin 4 | RA2/AN2/C12IN2-/VREF-/DACOUT — PORTA bit 2; analog input 2; comparator input; DAC output |
| Pin 5 | RA3/AN3/C12IN3+/VREF+ — PORTA bit 3; analog input 3; comparator input; external reference |
| Pin 6 | RA4/C1OUT/T0CKI/SRQ — PORTA bit 4; comparator 1 output; Timer0 clock; SR-latch Q output |
| Pin 7 | RA5/AN4/C2OUT/SRN — PORTA bit 5; analog input 4; comparator 2 output; SR-latch N output |
| Pin 8 | VSS — Ground reference |
| Pin 9 | RA7/OSC1/CLKIN — PORTA bit 7; oscillator input; external clock input |
| Pin 10 | RA6/OSC2/CLKOUT — PORTA bit 6; oscillator output; clock output |
| Pin 11 | RC0/SOSCO/T1CKI — PORTC bit 0; secondary oscillator output; Timer1 clock input |
| Pin 12 | RC1/SOSCI/T1OSO — PORTC bit 1; secondary oscillator input; Timer1 oscillator output |
| Pin 13 | RC2/CCP1/P1A — PORTC bit 2; CCP1 I/O; enhanced PWM output 1A |
| Pin 14 | RC3/SCK1/SCL1 — PORTC bit 3; MSSP1 SPI clock or I2C clock line |
| Pin 15 | RC4/SDI1/SDA1 — PORTC bit 4; MSSP1 SPI data in or I2C data line |
| Pin 16 | RC5/SDO1 — PORTC bit 5; MSSP1 SPI data out |
| Pin 17 | RC6/TX1/CK1 — PORTC bit 6; EUSART1 transmit or clock line |
| Pin 18 | RC7/RX1/DT1 — PORTC bit 7; EUSART1 receive or data line |
| Pin 19 | VSS — Ground reference (second) |
| Pin 20 | VDD — Positive supply voltage |
| Pin 21 | RB0/INT0/FLT0/AN12 — PORTB bit 0; external interrupt 0; PWM fault input; analog input 12 |
| Pin 22 | RB1/INT1/P1C/AN10 — PORTB bit 1; external interrupt 1; enhanced PWM output 1C; analog input 10 |
| Pin 23 | RB2/INT2/P1B/AN8 — PORTB bit 2; external interrupt 2; enhanced PWM output 1B; analog input 8 |
| Pin 24 | RB3/INT3/CCP2/AN9 — PORTB bit 3; external interrupt 3; CCP2 I/O; analog input 9 |
| Pin 25 | RB4/P1D/AN11 — PORTB bit 4; enhanced PWM output 1D; analog input 11 |
| Pin 26 | RB5/P1E/AN13 — PORTB bit 5; enhanced PWM output 1E; analog input 13 |
| Pin 27 | RB6/PGC/ICSPCLK — PORTB bit 6; ICSP clock; ICD clock |
| Pin 28 | RB7/PGD/ICSPDAT — PORTB bit 7; ICSP data; ICD data |
Typical Applications
PIC18F25K22-I/SO is suitable for 7 applications: Battery-Powered IoT Sensor Node, Consumer Appliance Control Board, Small BLDC Motor / Fan Control, Industrial Sensor Transmitter (4-20 mA / RS-485), USB-to-UART Bridge / HID Device (paired with USB controller), Smart Remote Control / HMI Front Panel, Automotive Interior Lighting Controller.
Battery-Powered IoT Sensor Node
The PIC18F25K22-I/SO suits multi-year battery IoT nodes because nanoWatt XLP deep sleep draws under 100 nA and the wide 1.8V-5.5V VDD lets you run directly from 2x AA alkaline cells down to 2.0V without boost. The 32KB Flash holds a LoRaWAN or BLE-Beacon stack alongside application logic, while the 10-bit ADC reads up to 19 analog sensors. With the 32kHz LFINTOSC running the RTCC, the MCU wakes every minute, samples, transmits, and returns to sleep - a duty cycle of <0.1% is realistic, enabling 10+ year battery life on 2x AA.
Recommended
Consumer Appliance Control Board
The 25 GPIO pins, 7 PWM outputs, and multiple timers of the PIC18F25K22-I/SO map directly onto washing-machine, dishwasher, and induction-cooktop user-interface boards driving segmented LCDs, buzzer, relays, and triac-fired heater elements. The 64MHz CPU provides the throughput for graphical UI state machines and the Enhanced USART links to a companion display or BLE module. Industrial-grade -40C to +85C operation tolerates the high-ambient environment inside a sealed appliance, while the wide SOIC package survives hand-soldered rework during prototyping and small-batch production.
Recommended
Small BLDC Motor / Fan Control
In small brushless DC fan and pump controllers up to 100W, the PIC18F25K22-I/SO runs a 6-step or basic FOC loop using its enhanced PWM module with complementary outputs and programmable dead time, plus the integrated 10-bit ADC for back-EMF sensing. The 64MHz / 16 MIPS CPU cycle budget leaves enough headroom for the control loop plus UART-based diagnostics, while the small 28-pin SOIC fits in the constrained end-of-motor PCB. The 1.8V-5.5V VDD lets a single 3.3V LDO power both logic and op-amps, simplifying BOM.
Recommended
Industrial Sensor Transmitter (4-20 mA / RS-485)
The PIC18F25K22-I/SO is a strong fit for loop-powered or RS-485 industrial transmitters because of its Enhanced USART supporting LIN/IrDA, plus nanoWatt XLP for low quiescent draw that does not starve the 4 mA loop budget. The 10-bit ADC with internal reference reads bridge and RTD sensors, the CTMU performs cold-junction compensation for thermocouples, and the wide 1.8V-5.5V VDD lets the same hardware handle both 24V loop and 3.3V RS-485 bus designs with minor BOM swaps.
Recommended
USB-to-UART Bridge / HID Device (paired with USB controller)
Although the PIC18F25K22-I/SO has no native USB, it pairs naturally with an external USB-UART bridge (CP2102, FT230X) to provide a low-power, field-upgradable serial interface for industrial and embedded devices. The two Enhanced USARTs allow simultaneous connection to a PC debug port and an external radio module. The 32KB Flash easily accommodates a custom command-line interpreter plus bootloader, and the ICSP/ICD interface keeps firmware updates simple in production.
Recommended
Smart Remote Control / HMI Front Panel
The PIC18F25K22-I/SO drives capacitive-touch front panels and IR remote controls, leveraging the CTMU (Charge Time Measurement Unit) for touch sensing on multiple keys and the MSSP ports to drive SPI OLED displays. The nanoWatt XLP sleep mode lets a battery-powered remote sit idle for years between user interactions, while 32KB Flash holds a full Unicode glyph map plus proprietary protocols. The SOIC package is robust enough for hand-assembly runs typical of low-volume CE products.
Recommended
Automotive Interior Lighting Controller
Within automotive interior lighting (ambient LED, dome, footwell) running off a 12V nominal bus, the PIC18F25K22-I/SO is often paired with the automotive-grade PIC18F25K22-I/SO in I-grade for cabin-area tasks where AEC-Q100 is not mandated. The 7 PWM outputs drive multi-channel LED strings via external MOSFETs, the Enhanced USART bridges to a body-control module, and nanoWatt XLP sleep modes keep quiescent draw below the typical 100 uA cabin-network limit. For AEC-Q100-qualified pins, see the PIC18F25K22-E/SO extended-temperature variant.
Recommended
Recommended Products Summary
Engineering reference data for PIC18F25K22-I/SO — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC18F25K22-E/SO | PIC18F26K22-I/SO | PIC18F24K22-I/SO | PIC18F25K20-I/SO | PIC18F25Q10-I/SO |
|---|---|---|---|---|---|---|
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Package | 28-pin SOIC wide (SO) | 28-pin SOIC wide (SO) - same | 28-pin SOIC wide (SO) - same | 28-pin SOIC wide (SO) - same | 28-pin SOIC wide (SO) - same | 28-pin SOIC (SO) - same |
| Flash Program Memory | 32 KB | 32 KB | 64 KB (+100%) | 16 KB (-50%) | 32 KB | 32 KB |
| RAM | 1536 bytes | 1536 bytes | 3896 bytes (+154%) | 768 bytes (-50%) | 1536 bytes | 1536 bytes |
| EEPROM | 256 bytes | 256 bytes | 1024 bytes (+300%) | 256 bytes | 256 bytes | 256 bytes |
| Maximum CPU Clock | 64 MHz | 64 MHz | 64 MHz | 64 MHz | 64 MHz | 64 MHz |
| Operating Temperature | -40 C to +85 C (Industrial) | -40 C to +125 C (Extended) | -40 C to +85 C (Industrial) | -40 C to +85 C (Industrial) | -40 C to +85 C (Industrial) | -40 C to +85 C (Industrial) |
| Low-Power Technology | nanoWatt XLP | nanoWatt XLP | nanoWatt XLP | nanoWatt XLP | nanoWatt XLP | nanoWatt XLP |
| Approximate 1k Pricing (USD) | $1.78 | $2.10 | $2.35 | $1.65 | $1.70 | $1.95 |
Key Differentiators
- Pin-compatible with PIC18F24K22 and PIC18F26K22 in same 28-pin SOIC footprint (vs PIC18F24K22-I/SO (16KB Flash) and PIC18F26K22-I/SO (64KB Flash))
- nanoWatt XLP deep-sleep under 100 nA (vs PIC18F25Q10-I/SO (newer migration target))
- Mature and widely stocked vs newer PIC18F25Q10 (vs PIC18F25Q10-I/SO)
Design Notes
For lowest standby current on PIC18F25K22-I/SO, configure the part for sleep mode with the LFINTOSC (31 kHz) driving RTCC, disable all unused peripherals via PMD register, switch MCLR to internal, and gate the ADC entirely. Measured deep-sleep current is under 100 nA at 25C with WDT and BOR disabled, per the datasheet's nanoWatt XLP section. Always include a 100 nF decoupling cap within 5 mm of VDD (pin 20) plus a 1-10 uF bulk capacitor.
For the 28-pin SOIC footprint, route ICSP signals (PGC/PGD on RB6/RB7) with short, parallel traces and add a 4-pin header (or test pad) for in-circuit programming. Keep analog traces (AN0-AN13) away from PWM outputs to minimize capacitive coupling into the ADC; if the PCB mixes both, dedicate separate ground return paths and a single-point tie between AGND and DGND. The exposed pad is N/A here (SOIC has no EP) - thermal dissipation is via the SOIC leads and board copper.
The PIC18F25K22-I/SO is a 5V-tolerant part with 1.8V-5.5V VDD; some peripherals (USART, ADC at high clock) require VDD above specific thresholds documented in the electrical characteristics table. A common mistake is configuring the ADC for a high clock at 3.3V that violates the minimum tad specification. Also note that the LFINTOSC accuracy (about +/-2% uncalibrated) is too coarse for asynchronous USART at high baud - use HFINTOSC with the PLL for UART work.
Compliance Information
RoHS compliant and lead-free per Microchip product page. Not AEC-Q100 qualified - choose a Q-grade or automotive-grade variant (e.g. PIC18F25K22-E/SO for extended temperature only; AEC-Q100 needs a separate qualification run) for automotive designs.
