PIC18LF45J11T-I/ML - 48MHz 8-bit MCU 32KB Flash 44-QFN | Microchip
MPN: PIC18LF45J11T-I/ML ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $4.62 | $4.62 |
| 10 | $4.15 | $41.50 |
| 100 | $3.68 | $368.00 |
| 500 | $3.29 | $1,645.00 |
| 1,000 | $2.94 | $2,940.00 |
| 1,600 | $2.78 | $4,448.00 |
PIC18LF45J11T-I/ML Overview
What is a PIC18 microcontroller? A PIC18 microcontroller is an 8-bit RISC (Reduced Instruction Set Computer) MCU from Microchip Technology's PIC18 family, sitting at the mid-range of Microchip's PIC microcontroller hierarchy. PIC18 -> 8-bit MCU -> microcontroller -> embedded processor -> semiconductor IC. The PIC18 core offers 77 instructions, hardware multiplier, 32-level stack, and C-friendly architecture, making it a step up from PIC16 in code density and interrupt handling while remaining more deterministic than 32-bit Cortex-M cores for simple real-time tasks.
Key features of the PIC18LF45J11T-I/ML include a 10-bit ADC with up to 13 channels, multiple communication peripherals (USB 2.0 FS, two I2C/SPI, two USART with LIN support), four 8-bit/16-bit timers, two analog comparators, and nanoWatt XLP power-saving modes that drop current consumption below 100 nA in sleep. The 48 MHz internal oscillator eliminates the need for an external crystal in many designs, while the 44-QFN package provides a compact 8x8 mm footprint with excellent thermal dissipation through the exposed pad.
The architecture uses a 16-bit instruction word with single-cycle execution for most instructions, giving an effective throughput of 12 MIPS at 48 MHz. The 32KB Flash supports self-programming and is partitioned into a bootloader region plus application code, while 4KB of SRAM supports data-heavy USB stacks and TCP/IP libraries. The integrated USB 2.0 full-speed transceiver and on-chip pull-up resistors remove the need for external USB PHY components in HID, CDC, or vendor-class device designs.
Typical applications include USB human-interface devices (HID keyboards, mice, game controllers), USB-to-UART bridges and virtual COM ports, industrial sensor nodes with LIN bus, low-power battery-powered IoT endpoints, and consumer appliances requiring capacitive-touch or analog front-end support. The combination of USB, ample RAM, and XLP sleep current makes it well-suited for always-on peripherals that must wake on interrupt and serve a USB host.
When designing with this device, note that the QFN-44 EP package requires reflow soldering and a thermal pad soldered to a ground copper pour for mechanical reliability. Programming is supported through Microchip's MPLAB X IDE with XC8 compiler; ICD3/Pickit 4 debug headers require dedicated pins (PGC/PGD) and may need isolation from application circuitry. Be sure to enable the internal weak pull-ups on unused pins to avoid floating-input current draw.
This page consolidates distributor pricing, drop-in alternatives in the same 44-QFN footprint, and practical design notes not always visible in the manufacturer datasheet.
Drop-in alternatives for PIC18LF45J11T-I/ML — 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 PIC18LF45J11T-I/ML (same form factor and footprint) — differing in Package, Timers, Program Memory (Flash), ADC, I/O Pins.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PIC18LF45J11-I/ML
✅ Drop-In📋 Reference alternative (not in catalog)
PIC18LF46J11T-I/ML
✅ Drop-In✓ In Stock
$3.17 / Unit
View Datasheet →PIC18LF45J10-I/ML
✅ Drop-In ⚠️ Specs Unverified📋 Reference alternative (not in catalog)
PIC18LF44J10-I/ML
✅ Drop-In ⚠️ Specs Unverified✓ In Stock
$2.2 / Unit
View Datasheet →PIC18F45J11T-I/ML
✅ Drop-In✓ In Stock
$3.2 / Unit
View Datasheet →PIC18LF4523-I/ML
✅ Drop-In ⚠️ Specs Unverified✓ In Stock
$4.12 / Unit
View Datasheet →PIC18LF45J11T-I/ML Maximum Ratings & Electrical Characteristics
| Core Architecture | PIC18 (8-bit RISC, 77 instructions) |
| Maximum CPU Clock | 48 MHz (12 MIPS) |
| Program Memory (Flash) | 32 KB (16K x 16 words) |
| Data Memory (SRAM) | 4 KB |
| Supply Voltage (VDD) | 2.0 V to 5.5 V |
| I/O Pins | 34 |
| Package | 44-pin QFN-EP (8x8 mm) |
| Operating Temperature | -40 C to +85 C (Industrial) |
| USB Peripheral | USB 2.0 Full-Speed with on-chip transceiver |
| ADC | 10-bit, up to 13 channels |
| Communication Peripherals | 2x I2C/SPI, 2x USART (LIN-capable), USB FS |
| Timers | 4 (8-bit/16-bit selectable) |
| Analog Comparators | 2 |
| Power-Saving Modes | nanoWatt XLP (sleep current < 100 nA typical) |
| Mounting Type | Surface Mount |
| MSL Level | MSL3 (per JEDEC J-STD-020) |
| RoHS Status | Compliant (lead-free QFN package) |
| Programming/Debug | ICSP via PGC/PGD; compatible with MPLAB X / XC8 / PICkit 4 / ICD 4 |
PIC18LF45J11T-I/ML 44-pin qfn-ep (8x8 mm) Pin Configuration Guide
Pin configuration for PIC18LF45J11T-I/ML (44-pin qfn-ep (8x8 mm) package). This digital IC includes GPIO, communication interfaces (UART, SPI, I2C), and power pins. Refer to the manufacturer datasheet for alternate pin functions and configuration options. Essential for embedded system design and PCB layout.
No detailed pinout data available for PIC18LF45J11T-I/ML.
Refer to the datasheet for full pin configuration.
Typical Applications
PIC18LF45J11T-I/ML is suitable for 6 applications: USB HID Peripherals, USB-to-UART Bridge, Industrial Sensor Nodes with LIN Bus, Battery-Powered IoT Endpoints, Consumer Appliance Control Panels, Capacitive Touch User Interfaces.
USB HID Peripherals
The PIC18LF45J11T-I/ML is well suited to USB Human Interface Devices such as keyboards, mice, gamepads, and numeric keypads because it integrates a USB 2.0 full-speed device peripheral with on-chip transceiver and internal pull-up resistor on the D+ line, eliminating the external PHY and pull-up BOM. Its 32 KB Flash holds the USB HID stack plus application firmware, while 4 KB SRAM supports HID report buffers and macro tables. Operating at 48 MHz (12 MIPS), the core services 1 ms USB polling intervals with ample headroom for debounce and RGB LED driving via PWM.
Recommended
USB-to-UART Bridge
In USB-to-UART bridges (virtual COM ports, debug consoles, RS-232 adapters), the PIC18LF45J11T-I/ML runs the USB CDC class and bridges data to its on-chip USART with hardware flow control, eliminating the need for an FTDI chip. The 4 KB RAM buffers full-speed USB packets at 12 Mbps without flow stall at typical 115200 baud rates. Industrial -40C to +85C operation lets the bridge operate inside outdoor enclosures alongside motors or heaters. Two USARTs allow simultaneous bridging plus a debug log channel.
Recommended
Industrial Sensor Nodes with LIN Bus
The PIC18LF45J11T-I/ML fits LIN (Local Interconnect Network) sensor nodes used in automotive body electronics and industrial distributed I/O, because both on-chip USARTs support LIN 1.3/2.0 with auto-baud detection and break-field generation. The 10-bit ADC with 13 input channels handles multiple analog sensors (temperature, pressure, level) from a single MCU. The wide 2.0 V to 5.5 V supply and -40 C to +85 C industrial range cover 12 V automotive battery drops and outdoor industrial rails without level shifting.
Recommended
Battery-Powered IoT Endpoints
Battery-powered IoT endpoints benefit from the PIC18LF45J11T-I/ML nanoWatt XLP technology, which drops sleep current below 100 nA while retaining RAM and interrupt-on-change wake-up, allowing multi-year coin-cell operation. The wide 2.0 V supply supports direct connection to single-cell Li-ion/LiFePO4 from full charge down to cutoff. The 32 KB Flash stores TLS handshake fragments or LoRaWAN stacks, and 4 KB RAM buffers sensor data before wake-up transmission. Two analog comparators allow zero-crossing wake from sensor events.
Recommended
Consumer Appliance Control Panels
Consumer appliances (washing machines, dishwashers, coffee makers, microwaves) use the PIC18LF45J11T-I/ML as a front-panel controller, because its 34 I/O pins drive multiplexed 7-segment or TFT displays, keypads, and buzzer PWM. The integrated USB FS allows factory firmware update or service diagnostics via a USB-C connector. The 5 V tolerance lets it directly drive relays and triacs through opto-isolators without level shifters. The 44-QFN-EP package fits inside the tight enclosure of compact appliances.
Recommended
Capacitive Touch User Interfaces
The PIC18LF45J11T-I/ML supports capacitive-touch user interfaces (touch buttons, sliders, proximity sensors) using its 10-bit ADC with charge-time measurement on mTouch-capable pins, plus hardware PWM for haptic feedback. The 4 KB RAM holds touch baseline history and gesture state machines, while 32 KB Flash stores the capacitive-touch library and application logic. Combined with the integrated USB, designers can deliver a touch panel that also enumerates as a USB HID composite device (touch + consumer-control) to the host PC.
Recommended
Recommended Products Summary
Engineering reference data for PIC18LF45J11T-I/ML — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC18LF45J11-I/ML | PIC18LF46J11T-I/ML | PIC18LF45J10-I/ML | PIC18LF44J10-I/ML | PIC18F45J11T-I/ML | PIC18LF4523-I/ML |
|---|---|---|---|---|---|---|---|
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Package | 44-QFN-EP (8x8 mm) | 44-QFN-EP (8x8 mm) - same | 44-QFN-EP (8x8 mm) - same | 44-QFN-EP (8x8 mm) - same | 44-QFN-EP (8x8 mm) - same | 44-QFN-EP (8x8 mm) - same | 44-QFN-EP (8x8 mm) - same |
| Flash Memory | 32 KB | 32 KB | 64 KB | 32 KB | 16 KB | 32 KB | 32 KB |
| SRAM | 4 KB | 4 KB | 4 KB | 2 KB | 4 KB | 4 KB | 2 KB |
| Maximum Clock | 48 MHz (12 MIPS) | 48 MHz (12 MIPS) | 48 MHz (12 MIPS) | 48 MHz (12 MIPS) | 48 MHz (12 MIPS) | 48 MHz (12 MIPS) | 40 MHz (10 MIPS) |
| Supply Voltage | 2.0 V to 5.5 V | 2.0 V to 5.5 V | 2.0 V to 5.5 V | 2.0 V to 5.5 V | 2.0 V to 5.5 V | 2.0 V to 3.6 V | 2.0 V to 5.5 V |
| USB 2.0 Peripheral | Yes (Full-Speed) | Yes (Full-Speed) | Yes (Full-Speed) | No | No | Yes (Full-Speed) | No |
| I/O Pins | 34 | 34 | 34 | 34 | 34 | 34 | 34 |
| Operating Temperature | -40 C to +85 C | -40 C to +85 C | -40 C to +85 C | -40 C to +85 C | -40 C to +85 C | -40 C to +85 C | -40 C to +85 C |
Key Differentiators
- Integrated USB 2.0 Full-Speed with on-chip transceiver (vs PIC18LF45J10-I/ML)
- Wide-voltage 2.0-5.5 V supply range (vs PIC18F45J11T-I/ML)
- Higher 12 MIPS throughput than legacy PIC18F4523 (vs PIC18LF4523-I/ML)
- 4 KB SRAM vs 2 KB on lower-tier PIC18LF45J10 (vs PIC18LF45J10-I/ML)
Design Notes
The PIC18LF45J11T-I/ML in 44-QFN-EP (8x8 mm) dissipates up to approximately 800 mW at 48 MHz and 5.5 V into the exposed thermal pad, which must be soldered to a copper ground pour of at least 1 square inch to keep junction temperature below 125 C. Without the thermal pad connection, the package has very high thermal resistance and can overheat during heavy USB activity. Estimated: assume 8 mm^2 thermal pad with 4-layer 1-oz copper pours gives theta_JA ~28 C/W.
Place the 0.1 uF VDD decoupling capacitor within 3 mm of the VDD pins, and a bulk 1 uF to 10 uF capacitor on the same power trace within 10 mm. The USB D+ and D- traces must be routed as a 90-ohm differential pair, length-matched within 2 mm, and kept away from clock or switching traces. The exposed thermal pad requires an array of thermal vias (typically 9-16 vias on 1.0-1.2 mm pitch) to the inner ground plane for heat sinking.
The PIC18LF45J11T-I/ML requires configuration bits (CONFIG1L through CONFIG5L/H) to be programmed correctly for oscillator selection, brown-out voltage, and watchdog timer before the device will run reliably. Unprogrammed configuration bits default to a state that disables the PLL and selects internal RC. Always use MPLAB X to generate the configuration settings and verify the .hex file before production programming. ICD debugging requires the PGC/PGD pins to be accessible and not loaded by external circuitry.
When using the USB peripheral, the VUSB pin requires a 0.47 uF decoupling capacitor close to the pin to filter internal transceiver noise. Internal pull-up on D+ is selectable via firmware but defaults OFF; enable it only when the device is configured, never at POR, to avoid enumerating before firmware initializes. For USB-IF compliance, the D+/D- traces must be 90-ohm differential with no stubs.
Compliance Information
RoHS-compliant lead-free QFN package per Microchip product page. Halogen-free status not explicitly stated in the indexed sources. Not AEC-Q100 qualified - the PIC18 family does not include automotive-grade variants in the LF45J11 sub-family.
