PIC18F44J50T-I/PT - 48MHz 8-bit USB MCU, 16KB Flash | Microchip
MPN: PIC18F44J50T-I/PT ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $4.3 | $4.30 |
| 10 | $3.87 | $38.70 |
| 100 | $3.45 | $345.00 |
| 500 | $2.95 | $1,475.00 |
| 1,000 | $2.55 | $2,550.00 |
PIC18F44J50T-I/PT 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. The PIC18F44J50 family belongs to the PIC18 8-bit architecture (Harvard RISC, modified instruction set), positioned under the broader PIC microcontroller umbrella and Microchip's megaAVR/XLP families. It targets cost-sensitive embedded designs where USB connectivity and ultra-low-power operation are both required.
Key features include 36 digital I/O pins, a 10-bit ADC with up to 13 channels, two comparators, two USART modules, two MSSP (SPI/I2C) modules, and dedicated USB SIE hardware. The nanoWatt XLP technology provides deep-sleep current under 100 nA, enabling battery-powered USB peripherals that can wake on USB activity. The on-chip full-speed USB 2.0 controller eliminates external PHY, reducing BOM cost and PCB area versus discrete USB solutions.
Architecture is a modified Harvard RISC core with a 16-bit instruction word and 8-bit data path, 32-level hardware stack, and configurable 8x8 multiplier. The peripheral set is mapped via the standard PIC18 SFR layout, supported by MPLAB X IDE and the free XC8 compiler. Internal PLL synthesizes 48 MHz from the 8 MHz internal oscillator for USB full-speed operation.
Typical applications include USB Human Interface Devices (HID) such as keyboards, mice, and game controllers, USB-to-UART virtual COM port adapters, low-power sensor data loggers with USB charging, USB-based firmware bootloaders/programmers, and industrial data acquisition nodes. The combination of native USB, XLP deep sleep, and 36 I/O makes the part a frequent choice for compact, low-power USB peripherals.
Designers should plan for a 3.3V-only supply (the J50 family is not 5V tolerant), use the internal 8 MHz oscillator to minimize BOM, and ensure VUSB 3.3V is decoupled with 1 uF + 100 nF per the reference design. Pin assignments in TQFP-44 are pin-compatible with PIC18F4550 family, simplifying migration from 5V to 3.3V designs.
This page synthesizes distributor pricing, drop-in TQFP-44 alternatives, and practical design notes not found in the manufacturer datasheet, intended as an engineering reference.
Drop-in alternatives for PIC18F44J50T-I/PT — 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 PIC18F44J50T-I/PT (same form factor and footprint) — differing in Operating Temperature, Package, ADC, Core Architecture, Timers.
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Request AlternativesPIC18F44J50T-I/PT Maximum Ratings & Electrical Characteristics
| Core Architecture | PIC18 8-bit RISC (modified Harvard) |
| Program Memory (Flash) | 16 KB (8K x 16 words) |
| Data RAM | 4 KB |
| Maximum Clock Frequency | 48 MHz |
| Supply Voltage (VDD) | 2.0 V to 3.6 V |
| Operating Temperature | -40C to +85C (Industrial, "I") |
| I/O Pins | 36 |
| ADC | 10-bit, up to 13 channels |
| USB | USB 2.0 Full-Speed (12 Mbps), integrated SIE + transceiver |
| USART | 2 modules |
| MSSP (SPI/I2C) | 2 modules |
| Comparators | 2 |
| Timers (8/16-bit) | 2 x 8-bit, 3 x 16-bit |
| PWM Outputs | 5 CCP / 3 ECCP channels |
| nanoWatt XLP Deep Sleep Current | Under 100 nA (typical) |
| Package | 44-pin TQFP (PT), 10x10 mm |
| Mounting Type | Surface Mount |
| MSL Level | 3 |
| RoHS Status | Compliant |
PIC18F44J50T-I/PT Pin Configuration
| Pin 1 | RA0/AN0 — Digital I/O / Analog input channel 0 |
| Pin 2 | RA1/AN1 — Digital I/O / Analog input channel 1 |
| Pin 3 | RA2/AN2/VREF- — Digital I/O / Analog input / ADC VREF- |
| Pin 4 | RA3/AN3/VREF+ — Digital I/O / Analog input / ADC VREF+ |
| Pin 5 | RA4/T0CKI — Digital I/O / Timer0 clock input |
| Pin 6 | RA5/AN4 — Digital I/O / Analog input channel 4 |
| Pin 7 | RA6/OSC2/CLKO — Digital I/O / Oscillator output / Clock output |
| Pin 8 | RA7/OSC1/CLKI — Digital I/O / Oscillator input / Clock input |
| Pin 9 | VSS — Ground |
| Pin 10 | VDD — Positive supply (2.0-3.6V) |
| Pin 11 | RB0/AN12/INT0 — Digital I/O / Analog input / External interrupt 0 |
| Pin 12 | RB1/AN10/INT1 — Digital I/O / Analog input / External interrupt 1 |
| Pin 13 | RB2/AN8 — Digital I/O / Analog input |
| Pin 14 | RB3/AN9 — Digital I/O / Analog input |
| Pin 15 | RB4/AN11 — Digital I/O / Analog input |
| Pin 16 | RB5/KBI1 — Digital I/O / Keyboard interrupt |
| Pin 17 | RB6/KBI2/PGC — Digital I/O / Keyboard interrupt / ICSP clock |
| Pin 18 | RB7/KBI3/PGD — Digital I/O / Keyboard interrupt / ICSP data |
| Pin 19 | VSS — Ground |
| Pin 20 | VDD — Positive supply (2.0-3.6V) |
| Pin 21 | RC0/T1CKI — Digital I/O / Timer1 clock input |
| Pin 22 | RC1/T1OSI — Digital I/O / Timer1 oscillator input |
| Pin 23 | RC2/T1OSO — Digital I/O / Timer1 oscillator output |
| Pin 24 | VUSB — USB internal transceiver 3.3V supply |
| Pin 25 | VBUS — USB VBUS sense input (5V tolerant) |
| Pin 26 | D- — USB D- data line |
| Pin 27 | D+ — USB D+ data line |
| Pin 28 | RC6/TX/CK — Digital I/O / USART TX / USART clock |
| Pin 29 | RC7/RX/DT — Digital I/O / USART RX / USART data |
| Pin 30 | VSS — Ground |
| Pin 31 | VDD — Positive supply (2.0-3.6V) |
| Pin 32 | RD0 — Digital I/O |
| Pin 33 | RD1 — Digital I/O |
| Pin 34 | RD2 — Digital I/O |
| Pin 35 | RD3 — Digital I/O |
| Pin 36 | RC4/SDA — Digital I/O / I2C data |
| Pin 37 | RC5/SCL — Digital I/O / I2C clock |
| Pin 38 | RD4 — Digital I/O |
| Pin 39 | RD5 — Digital I/O |
| Pin 40 | RD6 — Digital I/O |
| Pin 41 | RD7 — Digital I/O |
| Pin 42 | VSS — Ground |
| Pin 43 | VDD — Positive supply (2.0-3.6V) |
| Pin 44 | RE3 — Digital I/O (MCLR alternate on J50 family) |
Typical Applications
PIC18F44J50T-I/PT is suitable for 6 applications: USB HID Peripherals (Keyboard / Mouse / Game Controller), USB-to-UART Virtual COM Port Adapter, Low-Power Battery USB Sensor Data Logger, USB Firmware Bootloader / In-System Programmer, Industrial USB Data Acquisition Node, USB Audio Class Device (Headset / Speaker Interface).
USB HID Peripherals (Keyboard / Mouse / Game Controller)
The PIC18F44J50T-I/PT is well-suited to USB HID peripherals because it integrates a full-speed USB 2.0 SIE and transceiver on-chip, eliminating the need for an external PHY and reducing BOM by 1-2 ICs versus MCU-plus-FTDI designs. Operating at 48 MHz, the device handles HID report polling (1 ms intervals) and key matrix scanning across its 36 I/O pins, while nanoWatt XLP deep sleep under 100 nA lets battery-powered mice run for years on a single AA cell. Per Microchip application note AN1199, the recommended firmware uses the USB Framework and HID class driver, with D+ pull-up enabled via the UCON register for bus-powered enumeration.
Recommended
USB-to-UART Virtual COM Port Adapter
Virtual COM port adapters using the PIC18F44J50T-I/PT leverage the on-chip USB SIE and one of the two on-chip USARTs to present a CDC class device over USB, exposing a serial port to the host PC without driver installation on modern OSes. The 48 MHz core and 4 KB RAM comfortably run the CDC class driver and TX/RX ring buffers at full USB throughput (12 Mbps), while the 3.3V VUSB rail directly powers the IC from USB. Per Microchip AN1167 and the PIC18F46J50 family datasheet, designers should use the internal 8 MHz oscillator with PLL enabled, and ensure VUSB decoupling uses 1 uF ceramic + 100 nF for USB-IF compliance testing.
Recommended
Low-Power Battery USB Sensor Data Logger
For battery-powered USB-charged sensor data loggers, the PIC18F44J50T-I/PT's nanoWatt XLP technology is the key advantage - quiescent current below 100 nA in deep sleep allows multi-year shelf life on a CR2032 coin cell, while integrated USB provides periodic data download and battery charging without external PHYs. The 10-bit ADC with up to 13 input channels handles temperature, voltage, and battery monitoring, and the 36 I/O accommodate SPI/I2C sensor chains. Per Microchip TB3065 (XLP design tips), the recommended pattern wakes the MCU on a RTCC alarm or USB attach interrupt, takes an ADC reading, stores to Flash, and re-enters deep sleep.
Recommended
USB Firmware Bootloader / In-System Programmer
The PIC18F44J50T-I/PT supports USB-based firmware updates via the Microchip HID bootloader (AN1310), which exposes the device as a HID class device so no host driver is needed - critical for field updates where customer PCs may not allow unsigned drivers. The 16 KB Flash is sufficient to hold a 4 KB USB bootloader in the boot block plus 12 KB application code, with the bootloader occupying the high-memory region protected by configuration bits. Per Microchip AN1310, designers should size the application below the boot block boundary, set CP fuses carefully, and verify against the latest bootloader source.
Recommended
Industrial USB Data Acquisition Node
Industrial data acquisition nodes use the PIC18F44J50T-I/PT as a low-cost USB endpoint for analog and digital sensor collection. The 13-channel 10-bit ADC and 36 I/O accept multiple sensor inputs simultaneously, the 2 USARTs interface RS485 / RS232 transducer chains, and the on-chip USB streams data to the host at full-speed rates. The industrial -40C to +85C temperature range (E-Plus suffix variant) supports factory floor deployment, and nanoWatt XLP allows the node to enter deep sleep between sample windows. Per Microchip AN1160 (USB CDC), a typical firmware uses interrupt-driven ADC + USB bulk transfer for sustained throughput.
Recommended
USB Audio Class Device (Headset / Speaker Interface)
USB audio class devices such as USB headsets and speaker interfaces use the PIC18F44J50T-I/PT as a USB controller that bridges to an external audio DAC via the on-chip MSSP SPI/I2C and PWM peripherals. While the MCU is not a high-fidelity audio DSP, its 48 MHz core handles USB isochronous transfers (1 ms frame, 48 kHz stereo) and basic sample-rate conversion, and the integrated USB eliminates external PHY cost. Per Microchip AN1227 (USB Audio), the recommended firmware uses the USB isochronous endpoint and DMA-assisted SPI to offload the CPU.
Recommended
Recommended Products Summary
Engineering reference data for PIC18F44J50T-I/PT — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC18F44J50-I/PT | PIC18F46J50-I/PT | PIC18F45J50-I/PT | PIC18F44J11-I/ML | PIC18F44J10-I/PT |
|---|---|---|---|---|---|---|
| Package | TQFP-44 (PT) 10x10 mm | TQFP-44 (PT) 10x10 mm - same | TQFP-44 (PT) 10x10 mm - same | TQFP-44 (PT) 10x10 mm - same | QFN-44 (ML) 8x8 mm | TQFP-44 (PT) 10x10 mm - same |
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Program Memory (Flash) | 16 KB | 16 KB | 64 KB | 32 KB | 16 KB | 16 KB |
| Data RAM | 4 KB | 4 KB | 8 KB | 4 KB | 4 KB | 4 KB |
| Maximum Clock Frequency | 48 MHz | 48 MHz | 48 MHz | 48 MHz | 48 MHz | 48 MHz |
| Integrated USB 2.0 FS | Yes | Yes | Yes | Yes | Yes | No |
| Supply Voltage | 2.0 V to 3.6 V | 2.0 V to 3.6 V | 2.0 V to 3.6 V | 2.0 V to 3.6 V | 2.0 V to 3.6 V | 2.0 V to 3.6 V |
| I/O Pins | 36 | 36 | 36 | 36 | 34 | 36 |
| XLP Deep Sleep Current | <100 nA | <100 nA | <100 nA | <100 nA | <100 nA | <100 nA |
Key Differentiators
- Integrated full-speed USB 2.0 SIE + transceiver (vs PIC18F44J10-I/PT)
- nanoWatt XLP deep sleep under 100 nA (vs PIC18F4550-I/P)
- Pin-compatible upgrade path to 64 KB PIC18F46J50-I/PT (vs PIC18F44J10-I/PT)
Design Notes
Estimated: at 48 MHz Fosc with 3.3V VDD, the PIC18F44J50T-I/PT active current is approximately 11-15 mA. Decouple VDD with 100 nF + 10 uF ceramic as close to the IC as possible, and place a 1 uF + 100 nF pair on VUSB (pin 24) per Microchip AN1160. Failing to decouple VUSB correctly causes USB enumeration failure and reduced signal integrity at the differential pair.
Route USB D+ and D- as a 90 ohm differential pair with matched length (within 150 mil) and continuous ground reference beneath. Per USB 2.0 spec, the D+/D- traces should be no longer than 50 mm on FR4, with no via stubs in the signal path. Place the 15 kohm pull-up resistor on D+ near the IC, NOT at the connector end.
Do not power the PIC18F44J50T-I/PT from 5V - the J50 family is NOT 5V tolerant. Migration from a PIC18F4550 design requires re-specifying I/O voltage compatibility with any 5V peripherals. Also, when using the internal USB pull-up via UCON register, disable the external pull-up; dual pull-ups cause enumeration failure on some hosts. Always verify the CONFIG1L IESO bit when transitioning from external to internal oscillator.
The TQFP-44 package has theta_JA of approximately 50 C/W on a standard 4-layer JEDEC test board. At maximum active current (~15 mA at 48 MHz / 3.6 V), worst-case power is 54 mW - well within the thermal envelope for industrial -40C to +85C operation without additional heatsinking. In deep sleep (<100 nA), power collapses to nanowatt levels.
Compliance Information
RoHS compliant per Microchip product page DS39931D. Industrial temperature grade (-40C to +85C). Not AEC-Q100 qualified - choose PIC18F family automotive variants for vehicle applications.