PIC18F25J50-I/SO - 8-bit USB MCU 48MHz 32KB Flash 28-SOIC
MPN: PIC18F25J50-I/SO ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $4.3 | $4.30 |
| 10 | $3.91 | $39.10 |
| 100 | $3.5 | $350.00 |
| 500 | $3.1 | $1,550.00 |
| 1,000 | $2.78 | $2,780.00 |
PIC18F25J50-I/SO Overview
A microcontroller (MCU) is a single-chip computer containing a CPU core, non-volatile program memory (Flash), working RAM, peripheral interfaces, and I/O pins. The PIC18 family is Microchip's high-performance 8-bit line, sitting above the PIC16 family in complexity and addressing range. The J-series PIC18FX5J50 family adds native full-speed USB 2.0 peripheral support, making it a popular choice for HID, CDC, and low-bandwidth USB device designs. Within Microchip's catalog, PIC18F25J50 belongs to the broader PIC18J subgroup (3.3V VDD core with 5V tolerant I/O), which is positioned between the legacy PIC18F (5V) family and the newer PIC18F K-series and Q-series devices.
Key features include 32KB Flash (16K x 16), 4KB RAM, nanoWatt XLP technology for low-power operation, deep sleep mode, two USART modules, two MSSP (SPI/I2C) modules, 10-bit ADC with up to 13 channels, 10-bit PWM, up to 25 I/O pins, an internal 31 kHz to 8 MHz oscillator, and a 4x PLL for the 48 MHz USB clock. The integrated USB 2.0 full-speed transceiver complies with USB 2.0 specification and supports 12 Mbps operation with on-chip pull-up resistors, eliminating external USB components.
Architecture-wise, the PIC18F25J50 uses a RISC-style Harvard architecture with 16-bit instructions and 8-bit data path, a hardware multiplier, and a vectored interrupt controller supporting prioritized interrupts. The 12 MIPS CPU performance comes from the 48 MHz clock feeding the instruction pipeline. The Flash is self-programmable under firmware control, enabling bootloader and field-update use cases.
Typical applications include USB HID peripherals (keyboards, mice, custom input devices), USB-to-UART bridges, USB CDC virtual COM ports, low-power sensor nodes with USB charging, industrial data loggers with USB export, and consumer electronics requiring USB device connectivity. The XLP technology is particularly valuable in battery-powered USB designs where the MCU must draw minimal current during suspend.
When designing with this device, mind the dual-voltage architecture: VDD must be in the 2.0V-3.6V range for the core, while most I/O are 5.5V tolerant. The USB bus-powered configuration uses the internal 3.3V regulator derived from VBUS. Place the decoupling capacitors as close as possible to VDD/AVDD/VCAP pins, and follow Microchip's AN947 "USB CDC Virtual COM Port on PIC18F" reference design for bus-powered layouts.
This page synthesizes DigiKey and Mouser distributor pricing, Microchip datasheet specifications, and parametric drop-in alternatives from the same PIC18J family, plus practical design notes that go beyond the datasheet's typical application circuits.
Drop-in alternatives for PIC18F25J50-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 PIC18F25J50-I/SO (same form factor and footprint) — differing in Package, ADC, Operating Temperature, I/O Pins, Timers.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PIC18F25J50T-I/SO
✅ Drop-In📋 Reference alternative (not in catalog)
PIC18F25J11-I/SO
📋 Reference alternative (not in catalog)
PIC18F2455-I/SO
✅ Drop-In✓ In Stock
$6.4 / Unit
View Datasheet →PIC18F2550-I/SO
✅ Drop-In✓ In Stock
$4.1 / Unit
View Datasheet →PIC18F2520-I/SO
✅ Drop-In✓ In Stock
$4.65 / Unit
View Datasheet →PIC18F2420-I/SO
✅ Drop-In📋 Reference alternative (not in catalog)
PIC18F25J50-I/SO Maximum Ratings & Electrical Characteristics
| Series | PIC® XLP™ 18J |
| Core Processor | PIC |
| Core Size | 8-Bit |
| Core Speed | 48 MHz (12 MIPS) |
| Program Memory | 32 KB (16K x 16) Flash |
| RAM | 4 KB |
| EEPROM | 0 (none) |
| Supply Voltage (VDD) | 2.0 V to 3.6 V |
| I/O Voltage Tolerance | 5.5 V (digital I/O) |
| Number of I/O Pins | 25 |
| USB Interface | USB 2.0 Full-Speed (12 Mbps), integrated transceiver |
| ADC | 10-bit, up to 13 channels |
| PWM Channels | 10-bit |
| USART | 2 |
| MSSP (SPI/I2C) | 2 |
| Timers | 4 (Timer0/1/2/3) |
| Package | 28-SOIC (0.3 inch, 7.50 mm body) |
| Operating Temperature | -40 C to +85 C (Industrial grade, -I) |
| Low-Power Technology | nanoWatt XLP with Deep Sleep mode |
| Mounting Type | Surface Mount |
| RoHS Status | Compliant |
PIC18F25J50-I/SO Pin Configuration
| Pin 1 | RA2 — Digital I/O / analog input AN2 |
| Pin 2 | RA3 — Digital I/O / analog input AN3 / VREF+ |
| Pin 3 | RA4 — Digital I/O / analog input AN4 |
| Pin 4 | RA5 — Digital I/O / analog input AN5 |
| Pin 5 | VCAP — Internal 3.3V regulator output, requires 10 uF decoupling cap to VSS |
| Pin 6 | VSS — Ground reference |
| Pin 7 | OSC1/CLKI/RA7 — Crystal oscillator input or external clock / GPIO |
| Pin 8 | OSC2/CLKO/RA6 — Crystal oscillator output or GPIO |
| Pin 9 | RC0 — Digital I/O |
| Pin 10 | RC1 — Digital I/O |
| Pin 11 | RC2 — Digital I/O |
| Pin 12 | RC3 — Digital I/O |
| Pin 13 | RC4 — Digital I/O |
| Pin 14 | VUSB — USB internal transceiver supply, requires decoupling cap |
| Pin 15 | D- — USB D- data line |
| Pin 16 | D+ — USB D+ data line |
| Pin 17 | RC6 — Digital I/O / TX1 (USART1) |
| Pin 18 | RC7 — Digital I/O / RX1 (USART1) |
| Pin 19 | VSS — Ground reference |
| Pin 20 | VDD — Positive supply voltage 2.0V-3.6V |
| Pin 21 | RB0 — Digital I/O / interrupt-on-change |
| Pin 22 | RB1 — Digital I/O / interrupt-on-change |
| Pin 23 | RB2 — Digital I/O / interrupt-on-change |
| Pin 24 | RB3 — Digital I/O / interrupt-on-change |
| Pin 25 | RB4 — Digital I/O / interrupt-on-change |
| Pin 26 | RB5 — Digital I/O / interrupt-on-change / programming clock |
| Pin 27 | RB6 — Digital I/O / interrupt-on-change / programming data |
| Pin 28 | RB7 — Digital I/O / interrupt-on-change |
Typical Applications
PIC18F25J50-I/SO is suitable for 7 applications: USB HID Peripheral Device, USB-to-UART Bridge, Industrial Data Logger with USB Export, Consumer USB Charging Cradle, USB Custom Sensor Interface, Educational Microcontroller Board, Medical Device USB Connectivity.
USB HID Peripheral Device
The PIC18F25J50-I/SO is an ideal USB HID device controller with its integrated USB 2.0 full-speed transceiver (12 Mbps), 32KB Flash for HID descriptor tables and report buffers, and 4KB RAM for report ring buffers. The on-chip 3.3V regulator (powered from VBUS) and internal D+/D- pull-up resistors eliminate external USB components. In a keyboard or custom HID design, the 48 MHz CPU delivers 12 MIPS, sufficient for debouncing, matrix scan, and USB protocol handling. Microchip's MLA USB HID bootloader library fits in the Flash and supports field firmware updates.
Recommended
USB-to-UART Bridge
The PIC18F25J50-I/SO suits USB-to-UART bridge designs (USB CDC virtual COM port) where it converts USB packets to asynchronous serial via its two integrated USART modules. The 12 MIPS CPU handles USB bulk transfers, CDC ACM protocol, and UART FIFO bridging simultaneously. The 4KB RAM buffers CDC packets while the 32KB Flash stores the CDC stack plus application firmware. The integrated 3.3V regulator simplifies bus-powered designs, and the -I industrial temperature rating (-40C to +85C) covers industrial enclosure environments.
Recommended
Industrial Data Logger with USB Export
The PIC18F25J50-I/SO is well suited to industrial data loggers that periodically export captured data over USB. The 32KB Flash stores bootloader and firmware, the 4KB RAM buffers logged samples, and the 13-channel 10-bit ADC reads analog sensor data. nanoWatt XLP technology with deep sleep mode below 100 nA enables battery-powered field deployment where the MCU wakes periodically, samples, and returns to sleep. The -I industrial temperature grade ensures operation from -40C to +85C in factory and outdoor enclosures.
Recommended
Consumer USB Charging Cradle
The PIC18F25J50-I/SO is a strong choice for consumer USB charging cradles and accessory chargers that need USB enumeration plus custom charging profiles. The MCU negotiates USB bus power, monitors charging current via ADC, and reports status over USB CDC. The nanoWatt XLP deep sleep mode keeps idle cradle current negligible, and the integrated 3.3V regulator eliminates a separate LDO. With 25 I/O pins, designers have ample GPIO for LED indicators, button inputs, and I2C battery gauge communication.
Recommended
USB Custom Sensor Interface
The PIC18F25J50-I/SO works well in USB sensor interfaces that read environmental sensors (temperature, humidity, gas) over I2C/SPI and stream readings to a host PC. The two MSSP (SPI/I2C) modules handle multiple sensor buses, while USB bulk transfers deliver high-throughput data. The 4KB RAM is enough for FIFO buffers, and 32KB Flash accommodates sensor drivers, calibration data, and a CDC or vendor-class USB stack. The 5.5V-tolerant I/O allows direct interfacing to 5V sensor breakout boards from a 3.3V VDD core.
Recommended
Educational Microcontroller Board
The PIC18F25J50-I/SO is popular in educational and hobbyist development boards because of its integrated USB, generous 32KB Flash for student projects, and Microchip's free MPLAB X IDE plus XC8 compiler support. The 28-SOIC package is easy to breadboard via SOIC-to-DIP adapters, and the 25 I/O pins connect to typical peripherals (LEDs, buttons, UART, SPI, I2C). The XLP low-power features let students explore battery-powered designs and deep sleep without complex power management.
Recommended
Medical Device USB Connectivity
The PIC18F25J50-I/SO can be considered for medical accessory devices requiring USB device connectivity to host PCs, such as USB-connected thermometers, pulse oximeters, or pill dispensers. The integrated USB eliminates a separate transceiver, reducing BOM and PCB area. The industrial -I temperature grade ensures operation across clinical environments, and the 5.5V-tolerant I/O simplifies interfacing to 5V analog front ends. Note: medical designs still require IEC 60601-1 system-level compliance, which is the integrator's responsibility, not the MCU's.
Recommended
Recommended Products Summary
Engineering reference data for PIC18F25J50-I/SO — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC18F25J50T-I/SO | PIC18F25J11-I/SO | PIC18F2455-I/SO | PIC18F2550-I/SO | PIC18F2520-I/SO | PIC18F2420-I/SO |
|---|---|---|---|---|---|---|---|
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Package | 28-SOIC | 28-SOIC - same | 28-SOIC - same | 28-SOIC - same | 28-SOIC - same | 28-SOIC - same | 28-SOIC - same |
| Flash Memory | 32 KB | 32 KB | 32 KB | 24 KB (-25%) | 32 KB | 32 KB | 16 KB (-50%) |
| RAM | 4 KB | 4 KB | 4 KB | 2 KB (-50%) | 2 KB (-50%) | 1.5 KB (-62%) | 768 B (-81%) |
| Core Speed | 48 MHz (12 MIPS) | 48 MHz | 48 MHz | 48 MHz | 48 MHz | 40 MHz | 40 MHz |
| USB Interface | USB 2.0 Full-Speed (12 Mbps) integrated | USB 2.0 Full-Speed | No USB | USB 2.0 Full-Speed | USB 2.0 Full-Speed | No USB | No USB |
| Core Voltage (VDD) | 2.0V - 3.6V (3.3V typical, 5V-tolerant I/O) | 2.0V - 3.6V | 2.0V - 3.6V | 2.0V - 5.5V (5V core) | 2.0V - 5.5V (5V core) | 4.2V - 5.5V (5V core) | 2.0V - 5.5V (5V core) |
| Low-Power Technology | nanoWatt XLP with Deep Sleep | nanoWatt XLP | nanoWatt XLP | Standard | Standard | nanoWatt | nanoWatt |
| Approx. Unit Price (qty 1) | $4.30 | $4.35 | $3.20 | $5.10 | $4.95 | $4.70 | $4.20 |
Key Differentiators
- Integrated USB 2.0 full-speed transceiver with on-chip 3.3V regulator (vs PIC18F25J11-I/SO)
- Higher RAM (4KB vs 2KB) and nanoWatt XLP deep sleep (vs PIC18F2550-I/SO)
- Lower core voltage (3.3V vs 5V) with 5V-tolerant I/O (vs PIC18F2455-I/SO)
Design Notes
The PIC18F25J50 uses a dual-voltage architecture: VDD must be 2.0V-3.6V for the core, while most digital I/O are 5.5V tolerant. The internal 3.3V regulator output appears on the VCAP pin (pin 5) and must be decoupled with a 10 uF low-ESR ceramic capacitor to VSS. In USB bus-powered designs, tie VBUS to VDD through a 5V-tolerant regulator or rely on the internal regulator's VBUS input. Power-on reset (POR) requires VDD rise time less than 50 ms for reliable boot.
Place the VCAP 10 uF decoupling capacitor as close as possible to pin 5 with a short, wide ground trace to pin 6. The USB D+/D- traces (pins 15/16) must be routed as a 90-ohm differential pair with matched lengths and kept short to minimize reflections. The crystal oscillator traces (pins 7/8) should be guarded by a ground ring to reduce EMI. Follow Microchip's AN950 reference layout for USB-compliant designs to avoid EMI re-radiation failures.
Do not apply 5V directly to VDD - this will damage the J-series core. Use the internal 3.3V regulator via VCAP, or supply an external regulated 3.3V. Forgetting the VCAP capacitor causes unstable core voltage and erratic behavior. Disabling the USB module's internal pull-up resistor disables USB enumeration; ensure the firmware enables it via the UCON register before USB attach. Watch the PLL lock time (~2 ms) after enabling the 48 MHz USB clock.
Estimated: at 48 MHz, VDD=3.3V, and full I/O switching, the PIC18F25J50 core draws approximately 15-20 mA active (0.05-0.07 W dissipation). The 28-SOIC has theta_JA around 60-70 C/W, so junction temperature rise above ambient is about 4-5 C at room temperature - thermal management is generally not required for this MCU. However, in enclosed USB bus-powered designs, verify that the internal 3.3V regulator's thermal performance is adequate at maximum VBUS load.
The USB D+/D- lines require 27-33 ohm series termination resistors close to the MCU pins for USB 2.0 full-speed compliance per the USB specification. The VUSB pin (pin 14) must be decoupled with a 0.01 uF + 4.7 uF capacitor pair for the internal USB transceiver supply. For bus-powered designs, place a 1 uF bulk capacitor on VBUS. ESD protection (such as USBLC6-2SC6) on D+/D- is recommended for production designs to survive IEC 61000-4-2 contact discharge.
Compliance Information
RoHS and REACH compliant per Microchip product page. Industrial temperature grade -40C to +85C. Not AEC-Q100 qualified; for automotive applications use PIC18F46J50 or PIC18F25K50 automotive variants. Halogen-free per Microchip environmental compliance documentation.
