PIC18LF4450T-I/PT - 8-Bit 48MHz USB MCU, 16KB Flash, TQFP-44 | Microchip
MPN: PIC18LF4450T-I/PT ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $7.5 | $7.50 |
| 10 | $6.65 | $66.50 |
| 100 | $5.8 | $580.00 |
| 500 | $5.1 | $2,550.00 |
| 1,000 | $4.55 | $4,550.00 |
PIC18LF4450T-I/PT Overview
An 8-bit microcontroller (MCU) is a single-chip computer built around an 8-bit data-path CPU, on-chip program memory (ROM/Flash), data RAM, and a mix of peripherals such as timers, ADC, communication interfaces, and I/O pins. Within the broader taxonomy, the PIC18LF4450 belongs to the PIC18F high-performance flash family, which sits between baseline PIC10/12/16 parts and 16-bit PIC24/dsPIC devices, and is part of Microchip's microcontroller -> MCU -> embedded controller -> semiconductor hierarchy. The 'LF' prefix designates the low-voltage / low-power variant of the PIC18F4550.
Key features include 34 digital I/O pins, integrated Full-Speed USB 2.0 device/host/OTG transceiver with on-chip voltage regulator, 10-bit ADC, Enhanced Universal Synchronous Asynchronous Receiver Transmitter (EUSART), Master Synchronous Serial Port (MSSP) for SPI and I2C, and nanoWatt Technology power management with multiple idle/sleep modes. The Enhanced Flash offers 100K erase/write cycle endurance typical and program retention exceeding 40 years.
Architecturally, the PIC18LF4450 uses a 16-bit instruction word (8K × 16 = 16KB) with an 8-bit data path, Harvard architecture, and a hardware multiply unit. The integrated USB SIE handles low-level protocol, freeing the core from bit-banging and enabling CDC, HID, MSD and custom class firmware. The on-chip 3.3 V regulator provides up to 250 mA to external logic when the device is powered from 5 V.
Typical applications include USB peripherals (HID mice/keyboards, CDC serial bridges, MSD card readers), industrial control with USB diagnostics, embedded data loggers, and battery-powered sensor nodes. Designers value the part for collapsing a separate USB bridge chip and external LDO into a single MCU footprint.
When designing in the PIC18LF4450, ensure the 48 MHz HS oscillator uses the correct crystal and load capacitors, add a 1 µF bulk capacitor at VUSB and VDD, and reserve the D+/D- lines with 90-ohm differential routing. For low-power targets, leverage nanoWatt sleep modes and the on-board low-power Timer1 oscillator to reduce quiescent current below 1 µA.
This page synthesizes distributor pricing, parametric comparisons with PIC18F4550 and PIC18F46J50 drop-in alternatives, and practical design notes not collocated in the manufacturer datasheet.
Drop-in alternatives for PIC18LF4450T-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 PIC18LF4450T-I/PT (same form factor and footprint) — differing in Package, Timers, ADC, I/O Pins, Operating Temperature.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PIC18F4550-I/PT
✅ Drop-In✓ In Stock
$4.95 / Unit
View Datasheet →PIC18LF4550-I/PT
✅ Drop-In📋 Reference alternative (not in catalog)
PIC18F4550T-I/PT
✅ Drop-In📋 Reference alternative (not in catalog)
PIC18F4553-I/PT
✅ Drop-In📋 Reference alternative (not in catalog)
PIC18F4450-I/PT
✅ Drop-In ⚠️ Specs Unverified📋 Reference alternative (not in catalog)
PIC18F2455-I/PT
✅ Drop-In📋 Reference alternative (not in catalog)
PIC18LF4450T-I/PT Maximum Ratings & Electrical Characteristics
| Core | PIC18F 8-bit RISC |
| Instruction Set | 16-bit instruction word, 8-bit data path (Harvard) |
| Maximum Clock Frequency | 48 MHz (12 MIPS) |
| Program Memory Type | Enhanced Flash (self-programmable) |
| Program Memory Size | 16 KB (8K x 16 words) |
| Data RAM | 768 bytes |
| Data EEPROM | 256 bytes |
| Supply Voltage (VDD) | 2.0 V to 5.5 V |
| I/O Pins | 34 |
| USB Interface | USB 2.0 Full-Speed (12 Mbps), SIE + on-chip transceiver, device/host/OTG |
| ADC | 10-bit, up to 13 channels |
| Communication Peripherals | EUSART, MSSP (SPI / I2C) |
| Timers | Timer0, Timer1, Timer2, Timer3 (16-bit capable) |
| On-chip Voltage Regulator | 3.3 V, up to 250 mA (from VBUS or VIN) |
| Power-Saving Modes | nanoWatt Technology: Run, Idle, Sleep, RC_RUN, RC_IDLE, PRI_RUN, PRI_IDLE, SEC_RUN, SEC_IDLE |
| Operating Temperature | -40 C to +85 C (Industrial, 'I' suffix) |
| Package | 44-pin TQFP (PT), 10 x 10 mm, 0.8 mm pitch |
| Mounting Type | Surface Mount |
| MSL Level | 3 (168 hours) |
| RoHS Status | Compliant (Pb-free) |
PIC18LF4450T-I/PT Pin Configuration
| Pin 1 | RC2/P1A/CCP1 — Digital I/O RC2 / Enhanced PWM output P1A / Capture-Compare-PWM channel 1 |
| Pin 2 | RA0/AN0 — Digital I/O RA0 / analog input AN0 |
| Pin 3 | RA1/AN1 — Digital I/O RA1 / analog input AN1 |
| Pin 4 | RA2/AN2/VREF- — Digital I/O RA2 / analog input AN2 / ADC negative reference |
| Pin 5 | RA3/AN3/VREF+ — Digital I/O RA3 / analog input AN3 / ADC positive reference |
| Pin 6 | RA4/T0CKI/C1OUT — Digital I/O RA4 / Timer0 clock input / Comparator 1 output |
| Pin 7 | RA5/AN4/SS/C2OUT — Digital I/O RA5 / analog input AN4 / SPI slave select / Comparator 2 output |
| Pin 8 | RE0/RD/AN5 — Digital I/O RE0 / Parallel-port read strobe / analog input AN5 |
| Pin 9 | RE1/WR/AN6 — Digital I/O RE1 / Parallel-port write strobe / analog input AN6 |
| Pin 10 | RE2/CS/AN7 — Digital I/O RE2 / Parallel-port chip select / analog input AN7 |
| Pin 11 | VDD — Positive supply (2.0 V - 5.5 V) |
| Pin 12 | VSS — Ground reference |
| Pin 13 | OSC1/CLKI — Crystal oscillator input / external clock input |
| Pin 14 | OSC2/CLKO — Crystal oscillator output / clock output |
| Pin 15 | D- — USB D- differential data line |
| Pin 16 | D+ — USB D+ differential data line |
| Pin 17 | VUSB — USB internal 3.3 V regulator output (bypass 220 nF to ground) |
| Pin 18 | D-/RG4 — Dual-function: USB D- or digital I/O RG4 (overlap with pin 15 on this package variant) |
| Pin 19 | D+/RG5 — Dual-function: USB D+ or digital I/O RG5 (overlap with pin 16 on this package variant) |
| Pin 20 | RB0/AN12/INT0 — Digital I/O RB0 / analog input AN12 / external interrupt 0 |
| Pin 21 | RB1/AN10/INT1 — Digital I/O RB1 / analog input AN10 / external interrupt 1 |
| Pin 22 | RB2/AN8/INT2 — Digital I/O RB2 / analog input AN8 / external interrupt 2 |
| Pin 23 | RB3/AN9/CCP2 — Digital I/O RB3 / analog input AN9 / CCP2 |
| Pin 24 | RB4/AN11/KBI0 — Digital I/O RB4 / analog input AN11 / keyboard interrupt 0 |
| Pin 25 | RB5/KBI1/PGM — Digital I/O RB5 / keyboard interrupt 1 / LVP programming |
| Pin 26 | RB6/KBI2/PGC — Digital I/O RB6 / keyboard interrupt 2 / ICSP clock |
| Pin 27 | RB7/KBI3/PGD — Digital I/O RB7 / keyboard interrupt 3 / ICSP data |
| Pin 28 | VDD — Positive supply (2.0 V - 5.5 V) |
| Pin 29 | VSS — Ground reference |
| Pin 30 | RD0/SPP0 — Digital I/O RD0 / Streaming Parallel Port data bit 0 |
| Pin 31 | RD1/SPP1 — Digital I/O RD1 / Streaming Parallel Port data bit 1 |
| Pin 32 | RD2/SPP2 — Digital I/O RD2 / Streaming Parallel Port data bit 2 |
| Pin 33 | RD3/SPP3 — Digital I/O RD3 / Streaming Parallel Port data bit 3 |
| Pin 34 | RD4/SPP4 — Digital I/O RD4 / Streaming Parallel Port data bit 4 |
| Pin 35 | RD5/SPP5/P1B — Digital I/O RD5 / SPP data bit 5 / Enhanced PWM P1B |
| Pin 36 | RD6/SPP6/P1C — Digital I/O RD6 / SPP data bit 6 / Enhanced PWM P1C |
| Pin 37 | RD7/SPP7/P1D — Digital I/O RD7 / SPP data bit 7 / Enhanced PWM P1D |
| Pin 38 | RC0/T1OSO/T1CKI — Digital I/O RC0 / Timer1 oscillator output / Timer1 clock input |
| Pin 39 | RC1/T1OSI — Digital I/O RC1 / Timer1 oscillator input |
| Pin 40 | RC4/D-/VM — Digital I/O RC4 / alternate USB D- / USB VBUS monitor |
| Pin 41 | RC5/D+/VP — Digital I/O RC5 / alternate USB D+ / USB VBUS valid |
| Pin 42 | RC6/TX/CK — Digital I/O RC6 / EUSART TX / EUSART clock |
| Pin 43 | RC7/RX/DT — Digital I/O RC7 / EUSART RX / EUSART data |
| Pin 44 | VSS — Ground reference |
Typical Applications
PIC18LF4450T-I/PT is suitable for 7 applications: USB HID Peripherals (Keyboard, Mouse, Gamepad), USB CDC Virtual COM Port Bridge, Industrial USB Sensor / Data Logger, Battery-Powered Medical Monitoring Accessory, USB Mass-Storage Card Reader / Firmware Bricking Recovery Tool, USB Home Automation Bridge / IoT Gateway, Educational / Maker USB Development Platform.
USB HID Peripherals (Keyboard, Mouse, Gamepad)
The PIC18LF4450T-I/PT is well-matched to USB HID-class peripherals thanks to its integrated Full-Speed USB 2.0 SIE and on-chip transceiver. With 16 KB Flash, 768 B RAM, and 34 I/O pins, it can run Microchip's MLA USB stack and still leave headroom for matrix-scanning firmware, debouncing, and LED PWM control. The 48 MHz / 12 MIPS core sustains 1 ms HID polling without CPU starvation, and the 2.0-5.5 V supply range lets the device run directly from USB VBUS (5 V regulated down internally to 3.3 V) or from 2x AA cells in wireless designs.
Recommended
USB CDC Virtual COM Port Bridge
For legacy RS-232-to-USB bridging the PIC18LF4450T-I/PT provides the EUSART, USB SIE, and 48 MHz throughput required to stream 1 Mbaud without overrun. Place the part between an FTDI-style host and a target MCU; the 10-bit ADC can also monitor supply voltage or cable current. The 2.0 V VDD minimum means the bridge survives low-voltage hosts and battery-powered test gear, while the integrated 3.3 V regulator powers external level shifters without a discrete LDO.
Recommended
Industrial USB Sensor / Data Logger
Industrial data loggers benefit from the PIC18LF4450T-I/PT's industrial -40 C to +85 C rating, 13-channel 10-bit ADC, and USB connectivity for PC-side data extraction. The 16 KB Flash holds a 1 kHz sampling scheduler plus MSV/SD card or USB MSD file write, while 768 B RAM buffers up to 384 samples. The nanoWatt sleep modes drop quiescent current below 1 µA in field deployments, making the part viable for battery-only installations that periodically wake and dump logs over USB.
Recommended
Battery-Powered Medical Monitoring Accessory
In portable medical accessories the PIC18LF4450T-I/PT's 2.0 V minimum VDD enables operation from a single Li-ion cell down to its end-of-discharge voltage, while the integrated USB simplifies charging-cradle data sync. The MSSP port talks to an SPI ADC or I2C biosensor front-end, and the EUSART can drive a Bluetooth module. nanoWatt sleep modes (<1 µA) extend shelf life for emergency kits, and 34 I/O leaves room for buttons, displays, and buzzer control.
Recommended
USB Mass-Storage Card Reader / Firmware Bricking Recovery Tool
The PIC18LF4450T-I/PT can enumerate as a USB Mass Storage Device (MSD) when paired with an SPI Flash or SD card socket, providing an embedded bootable image writer or field-recovery tool. With 12 MIPS it handles USB MSD bulk transfers and FAT12/16 firmware updates without external DMA. The 2.0-5.5 V range means the same hardware works on USB-host 5 V rails and 3.3 V battery debuggers, ideal for development kits and brick-recovery dongles.
Recommended
USB Home Automation Bridge / IoT Gateway
In a home-automation bridge the PIC18LF4450T-I/PT aggregates Z-Wave, Zigbee or proprietary RF modules via UART/SPI and exposes a USB CDC or HID interface to a Raspberry-Pi-class host. The 34 I/O and 12 MIPS handle RF packet routing, while the 10-bit ADC monitors rail voltage and a thermistor. The low-voltage LF silicon means the same firmware runs on USB-powered hubs and on battery-backed mesh repeaters.
Recommended
Educational / Maker USB Development Platform
The PIC18LF4450T-I/PT is a popular teaching platform because it integrates USB without external bridge chips, runs Microchip's MPLAB X IDE and XC8 compiler for free, and exposes 34 I/O for breadboard-friendly TQFP breakout boards. The 48 MHz speed and 12 MIPS give students headroom to learn interrupt-driven USB stacks, while the 2.0 V operation allows experiments with solar or coin-cell supplies. PICKit3 / Snap programmer support makes it a standard curriculum part.
Recommended
Recommended Products Summary
Engineering reference data for PIC18LF4450T-I/PT — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC18F4550-I/PT | PIC18LF4550-I/PT | PIC18F4550T-I/PT | PIC18F4553-I/PT | PIC18F4450-I/PT | PIC18F2455-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 | TQFP-44 (PT, 10x10 mm) - same | TQFP-44 (PT, 10x10 mm) - same | TQFP-44 (PT, 10x10 mm) - same |
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Max Clock Frequency | 48 MHz (12 MIPS) | 48 MHz (12 MIPS) - same | 48 MHz (12 MIPS) - same | 48 MHz (12 MIPS) - same | 48 MHz (12 MIPS) - same | 48 MHz (12 MIPS) - same | 48 MHz (12 MIPS) - same |
| VDD Range | 2.0 V to 5.5 V | 4.2 V to 5.5 V | 2.0 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 |
| Flash Program Memory | 16 KB (8K x 16) | 32 KB (16K x 16) | 32 KB (16K x 16) | 32 KB (16K x 16) | 32 KB (16K x 16) | 16 KB (8K x 16) - same | 24 KB (12K x 16) |
| Data RAM | 768 bytes | 2048 bytes | 2048 bytes | 2048 bytes | 2048 bytes | 768 bytes - same | 2048 bytes |
| USB Interface | USB 2.0 FS, SIE + transceiver | USB 2.0 FS, SIE + transceiver - same | USB 2.0 FS, SIE + transceiver - same | USB 2.0 FS, SIE + transceiver - same | USB 2.0 FS, SIE + transceiver - same | USB 2.0 FS, SIE + transceiver - same | USB 2.0 FS, SIE + transceiver - same |
| I/O Pins | 34 | 35 | 35 | 35 | 35 | 34 - same | 24 (TQFP-44 package, fewer bonded I/O) |
| ADC Resolution | 10-bit | 10-bit - same | 10-bit - same | 10-bit - same | 12-bit | 10-bit - same | 10-bit - same |
Key Differentiators
- Only 2.0 V low-voltage variant in the PIC18F4550 family for battery-powered USB designs (vs PIC18F4550-I/PT)
- Highest memory density at this voltage node (vs PIC18F4553-I/PT)
- nanoWatt sleep below 1 µA while retaining USB SIE state (vs PIC18F46J50-I/PT)
Design Notes
Route the USB D+/D- differential pair with 90-ohm characteristic impedance, matched length within 150 mil, and a continuous ground reference plane on the layer immediately below. Place the 220 nF VUSB decoupling capacitor within 50 mil of pin 17 to suppress internal regulator ripple, and tie VBUS to pin 1 of the USB connector through a 10 µF bulk capacitor per USB 2.0 specification.
Do not enable the on-chip USB voltage regulator (CONFIG2L bit VREGEN) without populating the 220 nF VUSB bypass, otherwise the regulator output oscillates and corrupts USB signaling. For low-voltage designs operating below 4.2 V, set CONFIG1L to use the internal INTOSC at 8 MHz rather than an external HS crystal, because HS mode requires VDD > 4.2 V for guaranteed oscillator start-up.
Estimated: at 48 MHz, VDD = 5.0 V and all 34 I/O driving 20 pF loads at 10 MHz toggle, core and I/O current totals roughly 25 mA plus USB contributions. Place a 1 µF ceramic + 10 µF bulk on each VDD pin pair (11/12 and 28/29) within 100 mil, and route a star topology from the regulator to minimize ground bounce on the ADC reference inputs.
The 10-bit ADC achieves ±1 LSB accuracy only with a low-impedance source: add an external buffer op-amp (e.g., MCP6002) when the source impedance exceeds 2.5 kohm. Use a separate analog ground (AGND tied to VSS only at one point near the MCU) and decouple VREF+ independently from VDD to avoid digital switching noise coupling into conversion results.
Estimated: the 0.8 mm pitch TQFP-44 land pattern requires 0.4 mm-wide traces between pads to escape 34 signals; use via-in-pad with 0.3 mm drill on a 0.5 mm grid or fan-out to a 1.27 mm breakout row. Keep the HS crystal (pin 13/14) traces short (< 5 mm), symmetric, and surrounded by a ground guard ring to suppress radiated EMI that would otherwise fail USB radiated emissions tests.
Compliance Information
RoHS and REACH compliant per Microchip product environmental compliance page. Industrial temperature grade '-I' (suffix on 'T-I/PT') covers -40 C to +85 C; not AEC-Q100 qualified - for automotive USB designs use AEC-Q100 PIC18F4550-I/PT equivalent or PIC18F25K80 family.
