PIC18LF45K50-I/PT - 32KB Flash 8-bit XLP MCU 44-TQFP | Microchip
MPN: PIC18LF45K50-I/PT ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $4.2 | $4.20 |
| 10 | $3.78 | $37.80 |
| 100 | $3.36 | $336.00 |
| 500 | $2.94 | $1,470.00 |
| 1,000 | $2.52 | $2,520.00 |
PIC18LF45K50-I/PT Overview
An 8-bit microcontroller (MCU) is a single-chip computer that integrates a CPU, RAM, Flash program memory, and peripherals into one package. Within the broader taxonomy, the PIC18LF45K50 sits in the PIC18 enhanced mid-range family of Microchip's 8-bit PIC® RISC architecture, which provides up to 16 MIPS throughput at 48 MHz. The eXLP nanoWatt technology adds multiple low-power sleep modes (down to sub-uA standby), brown-out reset, and ultra-low-power RTCC, making the device suitable for battery-powered and energy-harvesting designs.
Key specifications include 32 KB Flash, 2 KB SRAM, 256 B EEPROM, 35 digital I/O pins, and rich connectivity: full-speed USB 2.0 (device/host/OTG), two USART modules, one SPI, and one I²C. The integrated 10-bit ADC with up to 25 channels and multiple timer/capture/PWM modules support mixed-signal embedded designs. The 44-TQFP package exposes 35 I/O lines plus dedicated USB D+/D- pins, supporting designs that need USB without an external transceiver.
Architecturally, the PIC18LF45K50 uses a 16-bit instruction word with 8-bit data path, hardware multiplier, and an 8-level hardware stack. The core supports both C and assembly development under MPLAB X IDE with the XC8 compiler, and is in-circuit serial programmable (ICSP) via two pins, enabling field firmware updates. The XLP nanoWatt features include low-power RTC, deep sleep with RAM retention, and ultra-low-power wake-on-interrupt.
Typical applications include USB HID peripherals (keyboards, mice, custom HID), battery-powered sensor nodes with USB charging, consumer electronics with USB-C interfaces, industrial data loggers with USB connectivity, and educational/development boards. The 1.8V minimum supply enables direct Li-ion or two-AA battery operation. The device also integrates a charge time measurement unit (CTMU) for capacitive touch and a 5-bit DAC for analog trimming.
When designing with the PIC18LF45K50, ensure the supply stays within 1.8V-3.6V for the LF variant; do not exceed 3.6V. Provide a 20 MHz crystal or use the internal 16 MHz HFINTOSC for USB full-speed operation, because USB requires a 48 MHz clock derived from the PLL. Decouple VDD with 100 nF ceramic at every supply pin and route the D+/D- pair as a 90-ohm differential.
This page synthesizes distributor pricing as of 2026-09-29, drop-in same-family PIC18LF alternatives from the Microchip catalogue, and practical USB + low-power design notes not compiled in the manufacturer datasheet alone.
Drop-in alternatives for PIC18LF45K50-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 PIC18LF45K50-I/PT (same form factor and footprint) — differing in Package, ADC, Timers, Core, Program Memory.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PIC18F45K50-I/PT
✅ Drop-In✓ In Stock
$2.74 / Unit
View Datasheet →PIC18LF45K50-I/P
✅ Drop-In ⚠️ Specs Unverified✓ In Stock
$2.55 / Unit
View Datasheet →PIC18LF45K50-E/PT
✅ Drop-In ⚠️ Specs Unverified📋 Reference alternative (not in catalog)
PIC18LF45J50-I/PT
✅ Drop-In✓ In Stock
$2.85 / Unit
View Datasheet →PIC18F45K50-E/PT
✅ Drop-In ⚠️ Specs Unverified📋 Reference alternative (not in catalog)
PIC18LF45K50-I/PT Maximum Ratings & Electrical Characteristics
| Core Processor | PIC |
| Core Size | 8-bit |
| Core Family | PIC18F XLP |
| Maximum CPU Speed | 48 MHz (16 MIPS) |
| Program Memory Type | Flash |
| Program Memory Size | 32 KB (16K x 16) |
| RAM Size | 2 KB |
| EEPROM Size | 256 B |
| Supply Voltage (LF) | 1.8 V to 3.6 V |
| Number of I/O Pins | 35 |
| Package | 44-pin TQFP (10x10 mm) |
| Mounting Type | Surface Mount |
| Operating Temperature | -40C to +85C (Industrial) |
| Connectivity | USB 2.0 FS (Device/Host/OTG), 2x USART, SPI, I2C |
| Peripherals | 10-bit ADC up to 25 ch, 8/16-bit Timers, PWM, CTMU, HLVD, BOR, WDT |
| Data Converters | 10-bit ADC, 5-bit DAC |
| Oscillator | Internal 16 MHz HFINTOSC + PLL to 48 MHz; external crystal supported |
| Program Memory | 32 KB |
| MSL Level | 3 (168 hours) |
| Lead-Free / RoHS | Yes / Compliant |
PIC18LF45K50-I/PT Pin Configuration
| Pin 1 | MCLR — Master Clear (Reset) input, active low |
| Pin 2 | RA0/AN0 — PORTA bit 0 / analog input 0 |
| Pin 3 | RA1/AN1 — PORTA bit 1 / analog input 1 |
| Pin 4 | RA2/AN2 — PORTA bit 2 / analog input 2 |
| Pin 5 | RA3/AN3 — PORTA bit 3 / analog input 3 / VREF+ |
| Pin 6 | RA4 — PORTA bit 4 |
| Pin 7 | RA5/AN4 — PORTA bit 5 / analog input 4 |
| Pin 8 | RE0/AN5 — PORTE bit 0 / analog input 5 |
| Pin 9 | RE1/AN6 — PORTE bit 1 / analog input 6 |
| Pin 10 | RE2/AN7 — PORTE bit 2 / analog input 7 |
| Pin 11 | VDD — Positive supply voltage (1.8V to 3.6V for LF) |
| Pin 12 | VSS — Ground reference |
| Pin 13 | OSC1/CLKIN — Oscillator input / external clock input |
| Pin 14 | OSC2/CLKOUT — Oscillator output / clock output |
| Pin 15 | RC4/D+ — PORTC bit 4 / USB D+ |
| Pin 16 | RC5/D- — PORTC bit 5 / USB D- |
| Pin 17 | RC6/TX/CK — PORTC bit 6 / USART TX / clock |
| Pin 18 | RC7/RX/DT — PORTC bit 7 / USART RX / data |
| Pin 19 | RD0 — PORTD bit 0 |
| Pin 20 | RD1 — PORTD bit 1 |
| Pin 21 | RD2 — PORTD bit 2 |
| Pin 22 | RD3 — PORTD bit 3 |
| Pin 23 | RC0 — PORTC bit 0 |
| Pin 24 | RC1 — PORTC bit 1 |
| Pin 25 | RC2 — PORTC bit 2 |
| Pin 26 | RC3 — PORTC bit 3 |
| Pin 27 | RB0 — PORTB bit 0 |
| Pin 28 | RB1 — PORTB bit 1 |
| Pin 29 | RB2 — PORTB bit 2 |
| Pin 30 | RB3 — PORTB bit 3 |
| Pin 31 | VSS — Ground reference |
| Pin 32 | VDD — Positive supply voltage |
| Pin 33 | RB4 — PORTB bit 4 |
| Pin 34 | RB5 — PORTB bit 5 |
| Pin 35 | RB6/PGC — PORTB bit 6 / ICSP clock |
| Pin 36 | RB7/PGD — PORTB bit 7 / ICSP data |
| Pin 37 | RD4 — PORTD bit 4 |
| Pin 38 | RD5 — PORTD bit 5 |
| Pin 39 | RD6 — PORTD bit 6 |
| Pin 40 | RD7 — PORTD bit 7 |
| Pin 41 | RA6 — PORTA bit 6 |
| Pin 42 | RA7 — PORTA bit 7 |
| Pin 43 | RE3 — PORTE bit 3 |
| Pin 44 | VUSB — USB internal 3.3V regulator output |
Typical Applications
PIC18LF45K50-I/PT is suitable for 6 applications: USB HID Peripherals, Battery-Powered Sensor Nodes, USB-C Charging Cradles and Docks, Industrial Data Loggers with USB, Consumer Electronics with USB-C, Educational Development Boards.
USB HID Peripherals
The PIC18LF45K50-I/PT is purpose-built for USB Human Interface Device peripherals such as keyboards, mice, game controllers, and custom HID gadgets. Its integrated full-speed USB 2.0 controller with on-chip transceiver eliminates the need for an external USB bridge, saving BOM cost and PCB area. The 32 KB Flash easily fits HID report descriptors and device firmware, while the 2 KB SRAM hosts USB endpoint buffers plus application stack. Designers get free USB stacks from Microchip's MLA library and benefit from 1.8V-3.6V operation enabling direct Li-ion or 2xAA battery power. Typical implementation routes D+/D- as a 90-ohm differential pair and uses internal 3.3V USB pull-ups.
Recommended
Battery-Powered Sensor Nodes
The XLP nanoWatt technology makes the PIC18LF45K50-I/PT ideal for battery-powered sensor nodes that spend most of their life in deep sleep. Sleep currents below 1 uA with RAM retention extend coin-cell or 2xAA battery life to multiple years. The 10-bit ADC with up to 25 channels digitizes sensor inputs, while I2C/SPI communicate with external digital sensors. The 1.8V minimum supply lets the device run directly from a single Li-ion cell without a boost converter. Combined with brown-out reset and ultra-low-power wake-on-interrupt, the part enables remote environmental monitoring, asset trackers, and IoT edge nodes where mains power is unavailable.
Recommended
USB-C Charging Cradles and Docks
USB Type-C charging cradles use the PIC18LF45K50-I/PT's USB peripheral for cable orientation detection and basic device enumeration. With 1.8V-3.6V operation, the MCU can power directly from VBUS after a 3.3V LDO, simplifying the power tree. The 16 MIPS throughput handles USB stack plus charging state machine in firmware, while PWM outputs drive LED status indicators. CTMU peripheral enables touch-button interfaces for the cradle surface. Combined with internal EEPROM for storing calibration data and 35 GPIO for accessory control pins, the K50 is a one-chip solution for low-cost charging docks that need USB awareness without full USB-PD complexity.
Recommended
Industrial Data Loggers with USB
Industrial data loggers benefit from the PIC18LF45K50-I/PT's combination of 32 KB Flash for buffer storage, 256 B EEPROM for non-volatile configuration, USB for data retrieval, and industrial -40C to +85C temperature grade. The 10-bit ADC with 25 channels accepts 4-20 mA or 0-10V transducer signals through external signal conditioning, while 2x USART interfaces accept RS-232/RS-485 transceivers for field-bus connectivity. The XLP low-power modes enable battery-backed operation during power outages. Industrial engineers value the on-chip USB because it eliminates the BOM cost of external FTDI bridges - logs are exported by plugging into any PC.
Recommended
Consumer Electronics with USB-C
Consumer products like smart-home hubs, fitness wearables with charging cradles, and educational STEM kits use the PIC18LF45K50-I/PT for USB-C connectivity at minimal cost. The 1.8V minimum supply enables single-cell Li-ion operation, while the 5 mm x 5 mm TQFP footprint fits compact consumer enclosures. Flash-resident USB HID or CDC stacks allow the device to appear as a keyboard, mouse, or virtual COM port without driver installation on most operating systems. The 32 KB Flash comfortably hosts application logic plus USB descriptors, and CTMU enables low-cost capacitive touch buttons for the device surface.
Recommended
Educational Development Boards
The PIC18LF45K50-I/PT is a popular choice for low-cost educational development boards thanks to integrated USB, free Microchip MPLAB X IDE + XC8 compiler toolchain, and a generous peripheral set at sub-$5 pricing. Universities and makers use it to teach embedded C programming, USB stack development, ADC sampling, PWM motor control, and I2C/SPI peripheral interfacing. The 44-TQFP package is breadboard-compatible through carrier boards, and ICSP allows firmware updates without removing the chip. Hobbyists value the extensive Microchip application notes, community libraries, and the ability to migrate code to higher-end PIC24/dsPIC parts without learning a new architecture.
Recommended
Recommended Products Summary
Engineering reference data for PIC18LF45K50-I/PT — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC18F45K50-I/PT | PIC18LF45K50-E/PT | PIC18LF45J50-I/PT | PIC18F45K50-E/PT | PIC18LF45K50-I/P |
|---|---|---|---|---|---|---|
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Package | 44-TQFP (10x10 mm) | 44-TQFP - same | 44-TQFP - same | 44-TQFP - same | 44-TQFP - same | 40-PDIP (different) |
| Supply Voltage Range | 1.8V to 3.6V | 1.8V to 5.5V | 1.8V to 3.6V | 2.0V to 3.6V | 1.8V to 5.5V | 1.8V to 3.6V |
| Flash Memory | 32 KB | 32 KB | 32 KB | 32 KB | 32 KB | 32 KB |
| RAM Size | 2 KB | 2 KB | 2 KB | 3.8 KB | 2 KB | 2 KB |
| USB Peripheral | USB 2.0 FS Device/Host/OTG | USB 2.0 FS | USB 2.0 FS | No USB | USB 2.0 FS | USB 2.0 FS |
| Operating Temperature | -40C to +85C | -40C to +85C | -40C to +125C | -40C to +85C | -40C to +125C | -40C to +85C |
| Max CPU Frequency | 48 MHz (16 MIPS) | 48 MHz (16 MIPS) | 48 MHz (16 MIPS) | 48 MHz (16 MIPS) | 48 MHz (16 MIPS) | 48 MHz (16 MIPS) |
Key Differentiators
- Lowest voltage range (1.8V) in K50 family (vs PIC18F45K50-I/PT)
- Integrated USB 2.0 full-speed controller (vs PIC18LF45J50-I/PT)
- Industrial -40C to +85C temperature grade as standard (vs PIC18F45K50-E/PT)
Design Notes
The PIC18LF45K50-I/PT operates from 1.8V to 3.6V VDD. Provide 100 nF ceramic decoupling on VDD pins 11 and 32, plus a 10 uF bulk capacitor near the supply. Estimated: at 48 MHz active current is approximately 12 mA; in deep sleep with RTCC, current drops below 1 uA per datasheet. Do NOT exceed 3.6V on the LF variant - use PIC18F45K50 for 5V systems. USB VBUS can be connected to VUSB (pin 44) via a 10 uF capacitor to power the internal 3.3V USB regulator.
USB differential pair D+ (pin 15) and D- (pin 16) must be routed as a 90-ohm differential pair with characteristic impedance matched per USB 2.0 spec. Place a 15 kohm pull-down on D- for full-speed device detection; the PIC18LF45K50 integrates this pull-up internally on D+. Keep the differential pair length matched within 150 mil. For USB-IF compliance, add common-mode choke and ESD protection array near the USB connector. Estimated: typical USB signal eye opening remains compliant with 50 mm trace lengths on FR-4 with proper impedance control.
Three pitfalls to avoid: (1) USB operation requires 48 MHz system clock - enable the PLL and configure HFINTOSC to 16 MHz as the PLL source, since internal 8 MHz is too slow. (2) Do not use the LF variant above 3.6V - electrical overstress damages the internal USB transceiver. (3) When migrating from PIC18F45K50 firmware to LF45K50, verify the BOR and HLVD voltage thresholds are within the LF supply range; default PIC18F BOR levels may be above 3.6V and trigger continuous resets on the LF part.
Compliance Information
RoHS and REACH compliant per Microchip product page. Industrial -40C to +85C temperature grade; AEC-Q100 qualified versions exist as PIC18F45K50-I/PT automotive variants. Lead-free and halogen-free per Microchip environmental compliance documentation.