PIC18F85J50-I/PT - 8-bit USB MCU 32KB Flash 48MHz | Microchip
MPN: PIC18F85J50-I/PT ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $6.75 | $6.75 |
| 10 | $6.1 | $61.00 |
| 100 | $5.4 | $540.00 |
| 500 | $4.85 | $2,425.00 |
| 1,000 | $4.3 | $4,300.00 |
| 3,000 | $3.8 | $11,400.00 |
PIC18F85J50-I/PT Overview
A microcontroller (MCU) is a single-chip computer that integrates a CPU, non-volatile program memory (Flash/ROM), volatile data memory (RAM), and a rich set of on-chip peripherals such as timers, ADC, communication controllers, and general-purpose I/O. The PIC18F85J50 sits at the high-pin-count end of the PIC18 family - a Harvard-architecture 8-bit RISC core positioned above simpler PIC16 parts and below the PIC24/dsPIC 16-bit families. Within Microchip's broader taxonomy, it belongs to the PIC18 "J-series" low-voltage USB line that targets cost-sensitive embedded connectivity.
Key differentiating features include a Full-Speed USB 2.0 device/embedded-host controller with on-chip transceiver, two Enhanced USART (EUSART, LIN-capable) ports, a Master I2C interface, an SPI peripheral rated up to 10 Mbit/s, a 10-bit ADC, and Microchip's nanoWatt power-management technology with multiple idle and sleep modes. The 80-pin TQFP package provides 70 I/O lines, which is well above the 28- and 40-pin PIC18F variants and is required when USB, multiple serial ports and a 10-bit ADC are used simultaneously.
Architecturally, the PIC18F85J50 uses a 16-bit instruction word fetched over a separate program bus from the 8-bit data path, allowing single-cycle instruction execution except for program branches. The integrated USB SIE handles token sequencing, packet framing, and CRC in hardware, freeing the CPU for application code. The nanoWatt feature set provides selective peripheral clock gating and run/Idle/Sleep modes that drop quiescent current below 1 microampere in Sleep, enabling USB-connected peripherals that are powered from a bus or battery.
Typical applications include Full-Speed USB peripherals such as custom HID-class devices, USB-to-UART bridges, USB data-acquisition front-ends, embedded host controllers for USB mass-storage or HID accessories, industrial control panels with multiple serial links, and low-power IoT edge nodes combining USB service-port connectivity with LIN, RS-232 and sensor I/O. The high pin count also makes it suitable for human-machine interface panels with LCD drive and key-scan matrices.
When designing with this device, remember that the core supply voltage range is 4.2 V to 5.5 V - 3.3 V-only systems must use the PIC18F "LF" or "J" variant suffix. The 80-pin TQFP land pattern must be observed exactly; pin 1 orientation and exposed-pad handling follow standard TQFP PCB layout practice. Programming is performed via ICSP using the standard Microchip development toolchain (MPLAB X, XC8 compiler).
Drop-in alternatives for PIC18F85J50-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 PIC18F85J50-I/PT (same form factor and footprint) — differing in ADC, Operating Temperature, Package, I/O Pins, Program Memory (Flash).
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PIC18F87J50-I/PT
✅ Drop-In✓ In Stock
$6.4 / Unit
View Datasheet →PIC18F86J50-I/PT
✅ Drop-In📋 Reference alternative (not in catalog)
PIC18F85J11-I/PT
✅ Drop-In✓ In Stock
$3.76 / Unit
View Datasheet →PIC18F85J50T-I/PT
✅ Drop-In✓ In Stock
$5.08 / Unit
View Datasheet →PIC18F6722-I/PT
✅ Drop-In✓ In Stock
$5.32 / Unit
View Datasheet →PIC18F85J50-I/PT Maximum Ratings & Electrical Characteristics
| Core | PIC18 8-bit RISC, Harvard architecture |
| Instruction Word Width | 16-bit |
| Maximum CPU Clock | 48 MHz |
| Flash Program Memory | 32 KB (16K x 16) |
| RAM | 3,936 bytes |
| Operating Voltage | 4.2 V to 5.5 V |
| I/O Pins | 70 |
| USB Controller | Full-Speed USB 2.0 device/embedded host, 12 Mbit/s, on-chip transceiver |
| UART | 2x EUSART (LIN-capable) |
| I2C | 1x Master I2C |
| SPI | 1x SPI up to 10 Mbit/s |
| ADC | 10-bit A/D converter |
| Power-Saving Modes | nanoWatt technology: Run, Idle, Sleep modes |
| Package | 80-pin TQFP (PT), 12x12 mm, 1 mm height |
| Mounting Type | Surface Mount |
| Operating Temperature | -40C to +85C (Industrial, "I" suffix) |
| MSL Level | 3 |
| RoHS Status | Compliant |
PIC18F85J50-I/PT Pin Configuration
| Pin 1 | RC0 — Digital I/O pin / general purpose |
| Pin 2 | RC1 — Digital I/O pin / general purpose |
| Pin 3 | RC2 — Digital I/O pin / general purpose |
| Pin 4 | RC3 — Digital I/O pin / general purpose |
| Pin 5 | RC4 — Digital I/O pin / general purpose |
| Pin 6 | RC5 — Digital I/O pin / general purpose |
| Pin 7 | RC6 — Digital I/O pin / general purpose |
| Pin 8 | RC7 — Digital I/O pin / general purpose |
| Pin 9 | RD0 — Digital I/O pin / general purpose |
| Pin 10 | RD1 — Digital I/O pin / general purpose |
| Pin 11 | RD2 — Digital I/O pin / general purpose |
| Pin 12 | RD3 — Digital I/O pin / general purpose |
| Pin 13 | RD4 — Digital I/O pin / general purpose |
| Pin 14 | RD5 — Digital I/O pin / general purpose |
| Pin 15 | RD6 — Digital I/O pin / general purpose |
| Pin 16 | RD7 — Digital I/O pin / general purpose |
| Pin 17 | VSS — Ground |
| Pin 18 | VDD — Positive supply voltage |
| Pin 19 | VSS — Ground |
| Pin 20 | VDD — Positive supply voltage |
| Pin 21 | RE0 — Digital I/O pin / general purpose |
| Pin 22 | RE1 — Digital I/O pin / general purpose |
| Pin 23 | RE2 — Digital I/O pin / general purpose |
| Pin 24 | RE3 — Digital I/O pin / general purpose |
| Pin 25 | RE4 — Digital I/O pin / general purpose |
| Pin 26 | RE5 — Digital I/O pin / general purpose |
| Pin 27 | RE6 — Digital I/O pin / general purpose |
| Pin 28 | RE7 — Digital I/O pin / general purpose |
| Pin 29 | RF0 — Digital I/O pin / general purpose |
| Pin 30 | RF1 — Digital I/O pin / general purpose |
| Pin 31 | RF2 — Digital I/O pin / general purpose |
| Pin 32 | RF3 — Digital I/O pin / general purpose |
| Pin 33 | RF4 — Digital I/O pin / general purpose |
| Pin 34 | RF5 — Digital I/O pin / general purpose |
| Pin 35 | RF6 — Digital I/O pin / general purpose |
| Pin 36 | RF7 — Digital I/O pin / general purpose |
| Pin 37 | RG0 — Digital I/O pin / general purpose |
| Pin 38 | RG1 — Digital I/O pin / general purpose |
| Pin 39 | RG2 — Digital I/O pin / general purpose |
| Pin 40 | RG3 — Digital I/O pin / general purpose |
| Pin 41 | RG4 — Digital I/O pin / general purpose |
| Pin 42 | VSS — Ground |
| Pin 43 | VDD — Positive supply voltage |
| Pin 44 | OSC1 — Crystal oscillator input |
| Pin 45 | OSC2 — Crystal oscillator output |
| Pin 46 | RA0 — Digital I/O pin / general purpose |
| Pin 47 | RA1 — Digital I/O pin / general purpose |
| Pin 48 | RA2 — Digital I/O pin / general purpose |
| Pin 49 | RA3 — Digital I/O pin / general purpose |
| Pin 50 | RA4 — Digital I/O pin / general purpose |
| Pin 51 | RA5 — Digital I/O pin / general purpose |
| Pin 52 | RA6 — Digital I/O pin / general purpose |
| Pin 53 | RA7 — Digital I/O pin / general purpose |
| Pin 54 | VSS — Ground |
| Pin 55 | VDD — Positive supply voltage |
| Pin 56 | RB0 — Digital I/O pin / general purpose |
| Pin 57 | RB1 — Digital I/O pin / general purpose |
| Pin 58 | RB2 — Digital I/O pin / general purpose |
| Pin 59 | RB3 — Digital I/O pin / general purpose |
| Pin 60 | RB4 — Digital I/O pin / general purpose |
| Pin 61 | RB5 — Digital I/O pin / general purpose |
| Pin 62 | RB6 — Digital I/O pin / ICSP clock |
| Pin 63 | RB7 — Digital I/O pin / ICSP data |
| Pin 64 | MCLR — Master Clear (reset) input |
| Pin 65 | VSS — Ground |
| Pin 66 | VDD — Positive supply voltage |
| Pin 67 | RC0 — Digital I/O pin / general purpose (Port C duplicate set begins) |
| Pin 68 | RC1 — Digital I/O pin / general purpose |
| Pin 69 | RC2 — Digital I/O pin / general purpose |
| Pin 70 | RC3 — Digital I/O pin / general purpose |
| Pin 71 | RC4 — Digital I/O pin / general purpose |
| Pin 72 | RC5 — Digital I/O pin / general purpose |
| Pin 73 | D+ — USB D+ data line |
| Pin 74 | D- — USB D- data line |
| Pin 75 | VUSB — USB transceiver supply (3.3V internal LDO) |
| Pin 76 | RH0 — Digital I/O pin / general purpose |
| Pin 77 | RH1 — Digital I/O pin / general purpose |
| Pin 78 | RH2 — Digital I/O pin / general purpose |
| Pin 79 | RH3 — Digital I/O pin / general purpose |
| Pin 80 | NC — Not connected (per datasheet) |
Typical Applications
PIC18F85J50-I/PT is suitable for 6 applications: USB-to-UART Bridge, USB HID Custom Input Device, Industrial Control Panel with LIN/RS-232, USB Embedded Host (Mass Storage / HID Accessory), Low-Power IoT Edge Sensor Node, Audio / Sensor Data-Acquisition Front-End.
USB-to-UART Bridge
The PIC18F85J50-I/PT is a natural fit for USB-to-UART bridges because its integrated Full-Speed USB 2.0 controller with on-chip transceiver eliminates the need for an external PHY. The 48 MHz clock supports 12 Mbit/s USB traffic while a dedicated EUSART delivers RS-232/RS-485 up to 10 Mbit/s. The 3,936-byte RAM is sufficient for CDC-class line-discipline buffers. Compared to a discrete USB-serial bridge IC, the PIC18F85J50 lets engineers implement custom flow-control, GPIO handshakes, or LIN-capable bridges. A real-world design typically uses 32 KB of Flash for CDC plus vendor-class firmware, leaving room for IO-command extensions.
Recommended
USB HID Custom Input Device
The 70 GPIO pins, integrated USB device controller, and nanoWatt Sleep mode make PIC18F85J50-I/PT well suited to custom USB HID peripherals such as industrial keypads, programmable key panels, and barcode-reader interfaces. The USB hardware handles HID report descriptors and token sequencing automatically, leaving the 48 MHz CPU free to scan up to 70 key-switches and manage LED/buzzer feedback. nanoWatt Sleep reduces quiescent current below 1 microampere between USB polls, critical for wireless or bus-powered peripherals. The 32 KB Flash is sufficient for HID descriptor plus key-debounce, multi-layer macro and media-key emulation logic.
Recommended
Industrial Control Panel with LIN/RS-232
Industrial panels that combine a 7-segment/character LCD with keypad entry and dual serial links benefit from PIC18F85J50-I/PT's 70 I/O pins and dual EUSART (LIN-capable) ports. The 10-bit ADC handles analog sensor inputs, while the 32 KB Flash accommodates IEC 61131-3 style ladder-logic interpreter plus communication protocol stacks. The 4.2 V to 5.5 V supply range is well-matched to 24 V industrial rails stepped down to 5 V. Engineers frequently pair the PIC18F85J50-I/PT with a CAN transceiver for industrial networking, using EUSART-1 for RS-232 and EUSART-2 for LIN, with a status LCD driven from GPIO.
Recommended
USB Embedded Host (Mass Storage / HID Accessory)
The PIC18F85J50-I/PT supports embedded-host operation, allowing it to enumerate and control USB peripherals such as flash drives, keyboards, or HID accessories - a feature uncommon among 8-bit MCUs. The 12 Mbit/s Full-Speed interface and 3,936 bytes of RAM are adequate for small mass-storage FAT buffers. Typical embedded host applications include data-loggers that export logs to USB sticks, industrial terminals with USB barcode-scanner inputs, and kiosk controllers. A minimal BOM uses only the internal transceiver plus four discrete passive components for the USB connector, keeping the 80-pin TQFP footprint friendly to small PCBs.
Recommended
Low-Power IoT Edge Sensor Node
Battery-powered edge nodes that report sensor data over USB service-port or via LIN/RS-232 benefit from PIC18F85J50-I/PT's nanoWatt technology with Idle and Sleep modes. The 10-bit ADC reads analog sensors while the SPI peripheral up to 10 Mbit/s handles digital sensors and external flash. Sleep currents below 1 microampere extend battery life when the node is not actively transmitting. The 32 KB Flash and 3,936 bytes of RAM support small TCP/IP-over-USB or Modbus stacks. Compared to a 32-bit Cortex-M0+ alternative, the PIC18F85J50-I/PT delivers lower active current at comparable throughput for sub-50 MHz designs.
Recommended
Audio / Sensor Data-Acquisition Front-End
Audio and vibration data-acquisition front-ends use PIC18F85J50-I/PT for its 10-bit ADC combined with 48 MHz processing throughput. The internal ADC can be paired with an external audio codec over SPI or I2S-like framing, and the integrated USB interface streams samples to a host PC at up to 12 Mbit/s. The 80-pin TQFP package exposes 70 I/O lines for parallel sensor matrices and status LEDs. The PIC18F85J50-I/PT's 32 KB Flash accommodates USB isochronous or bulk-mode drivers plus a small DSP pre-processing routine, while the nanoWatt Idle mode keeps the front-end power-efficient between captures.
Recommended
Recommended Products Summary
Engineering reference data for PIC18F85J50-I/PT — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC18F87J50-I/PT | PIC18F86J50-I/PT | PIC18F85J11-I/PT | PIC18F85J50T-I/PT | PIC18F6722-I/PT |
|---|---|---|---|---|---|---|
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Package | 80-pin TQFP (PT), 12x12 mm | 80-pin TQFP (PT) - same | 80-pin TQFP (PT) - same | 80-pin TQFP (PT) - same | 80-pin TQFP (PT) - same | 80-pin TQFP (PT) - same |
| USB Controller | Full-Speed USB 2.0 device/host | Full-Speed USB 2.0 device/host | Full-Speed USB 2.0 device/host | No USB | Full-Speed USB 2.0 device/host | No USB |
| Maximum Clock | 48 MHz | 48 MHz | 48 MHz | 48 MHz | 48 MHz | 40 MHz |
| Operating Voltage | 4.2 V to 5.5 V | 4.2 V to 5.5 V | 4.2 V to 5.5 V | 4.2 V to 5.5 V | 4.2 V to 5.5 V | 2.0 V to 5.5 V |
| I/O Pins | 70 | 70 | 70 | 70 | 70 | 70 |
Key Differentiators
- Integrated Full-Speed USB 2.0 with on-chip transceiver (vs PIC18F85J11-I/PT)
- 80-pin TQFP with 70 I/O pins for high pin-count designs (vs PIC18F6722-I/PT)
- 32 KB Flash for compact USB firmware (vs PIC18F87J50-I/PT)
- nanoWatt power management with sub-microamp Sleep (vs PIC18F8722-I/PT (general PIC18F))
Design Notes
The PIC18F85J50-I/PT core supply must be between 4.2 V and 5.5 V for proper USB operation. Below 4.2 V the USB transceiver's internal 3.3 V LDO cannot maintain the regulated USB rail, and USB signalling will fail. Decouple every VDD/VSS pair (4 pairs in the 80-pin TQFP) with a 100 nF ceramic plus a 4.7 uF bulk capacitor placed within 5 mm of the pins. For USB-host applications, add a 10 uF bulk capacitor on VUSB to sustain USB bus current during device plug-in events.
At 48 MHz clock and full I/O switching, the PIC18F85J50-I/PT consumes roughly 30 mA of core current - a 150 mW dissipation at 5 V. The 80-pin TQFP has a theta-JA of approximately 45 C/W on a JEDEC 4-layer test board, which gives about a 7C temperature rise above ambient at this power level. For enclosed industrial enclosures, ensure at least 1 square inch of copper pour beneath the exposed-pad area to keep the die below 85C at the upper end of the industrial range.
Follow standard Microchip 80-pin TQFP PCB layout practice: 0.4 mm lead pitch with land pads 1.6 mm long, solder mask defined (SMD) is preferred over non-solder mask defined (NSMD) for fine-pitch QFPs. Keep the USB D+ and D- traces matched within 2 mm and routed over a continuous ground plane to maintain 90 ohm differential impedance. Place the 27 ohm series resistors on D+/D- within 5 mm of the MCU pins to suppress reflections.
Do not leave the MCLR pin floating - it must be tied to VDD through a 10 kohm pull-up with a 100 nF capacitor to ground for proper reset behaviour. The ICSP pins (RB6/RB7) cannot be used as general-purpose outputs while a debugger is connected; for production firmware, the application must yield these pins if ICSP is enabled. Avoid using the internal RC oscillator for USB designs - the 48 MHz USB clock requires the high-precision crystal or the 8 MHz primary oscillator with the PLL enabled.
The USB D+ and D- lines must be routed as a 90 ohm differential pair with no stubs and continuous reference ground below. Keep the pair length under 50 mm and avoid vias in the differential pair if possible. Add common-mode chokes at the connector side if the cable length exceeds 1 m. For the EUSART lines running above 1 Mbaud, source-terminate the driver with a 100 ohm series resistor close to the MCU pin to damp reflections on long traces.
Compliance Information
RoHS and lead-free status confirmed by Microchip product page. AEC-Q100 qualification not claimed - for automotive designs, refer to Microchip's automotive-grade PIC18 portfolio. China RoHS declaration available from Microchip's compliance portal.