PIC18LF2455-I/SO - 8-bit USB MCU, 24KB Flash, 28-SOIC | Microchip
MPN: PIC18LF2455-I/SO ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $3.08 | $3.08 |
| 10 | $2.84 | $28.40 |
| 100 | $2.61 | $261.00 |
| 500 | $2.32 | $1,160.00 |
| 1,000 | $2.05 | $2,050.00 |
PIC18LF2455-I/SO Overview
An 8-bit microcontroller (MCU) is a single-chip computer that integrates a CPU, RAM, non-volatile program memory, and peripherals. The PIC18 family belongs to Microchip's enhanced Harvard-architecture 8-bit MCU line (PIC MCU -> 8-bit microcontroller -> microcontroller -> semiconductor IC), offering higher performance than baseline PIC16 parts through a 16-bit instruction word and a hardware multiplier. The "LF" prefix indicates an extended low-voltage operating range, distinguishing it from the standard PIC18F2455 (which targets 4.2V-5.5V nominal).
Key features include Full-Speed USB 2.0 (12 Mbit/s) with on-chip transceiver, three serial ports (FS-USB, I²C, SPI up to 10 Mbit/s, and EUSART with LIN capability), nanoWatt power management for sleep currents below 1 µA, 10-bit ADC up to 13 channels, and Capture/Compare/PWM modules. The 28-SOIC package provides a through-hole-replacement-friendly surface-mount footprint with 0.3-inch row spacing, suitable for hand-soldering and standard 28-pin DIP development boards via adapters.
Internally, the PIC18LF2455 uses a modified Harvard architecture with separate program Flash and data RAM buses, a 16-bit instruction set, and a hardware 8x8 multiplier that delivers ~10 MIPS at 48 MHz. The on-chip USB SIE handles Full-Speed USB signaling, frame generation, and endpoint management without external components, reducing BOM cost for HID, CDC, and vendor-class USB applications.
Typical applications include low-voltage USB peripherals (mouse, keyboard, custom HID devices), battery-powered data loggers with USB charging, industrial sensor nodes with LIN bus, and consumer electronics requiring embedded USB. The 2V minimum VDD makes it suitable for single-cell Li-ion or two-AA-cell designs.
When designing with this part, note that the LF grade requires careful attention to the VDD range - operation below 4.2V disables some USB transceiver parameters, and Flash programming voltage must be within the specified range. Use MPLAB X IDE with XC8 compiler and MPLAB SNAP or PICkit programmers for development.
This page synthesizes distributor pricing, same-family drop-in alternatives (PIC18F2455-I/SO, PIC18LF2550-I/SO), and practical design notes not found in the manufacturer datasheet alone.
Drop-in alternatives for PIC18LF2455-I/SO — 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 PIC18LF2455-I/SO (same form factor and footprint) — differing in ADC, Package, I/O Pins, Core Architecture, Timers.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PIC18LF2550-I/SO
✅ Drop-In✓ In Stock
$3.85 / Unit
View Datasheet →PIC18F2455-I/SO
✅ Drop-In✓ In Stock
$6.4 / Unit
View Datasheet →PIC18LF2450-I/SO
✅ Drop-In ⚠️ Specs Unverified📋 Reference alternative (not in catalog)
PIC18F2450-I/SO
✅ Drop-In ⚠️ Specs Unverified✓ In Stock
$3.55 / Unit
View Datasheet →PIC18F2550-I/SO
✅ Drop-In ⚠️ Specs Unverified✓ In Stock
$4.1 / Unit
View Datasheet →PIC18LF2455-I/SO Maximum Ratings & Electrical Characteristics
| Core Architecture | PIC 8-bit (Enhanced Harvard) |
| Program Memory Type | Flash |
| Program Memory Size | 24 KB (12K x 16) |
| RAM Size | 2048 bytes |
| EEPROM Size | 256 bytes |
| Maximum CPU Frequency | 48 MHz |
| Operating Voltage Range | 2.0 V to 5.5 V |
| USB Interface | USB 2.0 Full-Speed (12 Mbit/s), on-chip transceiver |
| Serial Interfaces | I²C, SPI (up to 10 Mbit/s), EUSART (LIN-capable) |
| ADC | 10-bit, up to 13 channels |
| I/O Pins | 23 (shared with peripherals) |
| Timers | 4 (Timer0/1/2/3) |
| Capture/Compare/PWM | 2 CCP modules, 1 ECCP |
| Package | 28-pin SOIC (SO) |
| Operating Temperature | -40 °C to +85 °C (Industrial) |
| Mounting Type | Surface Mount |
| MSL Level | 1 (unlimited) |
| RoHS Status | Compliant |
| Lead-Free | Yes |
| Programming Interface | ICSP (In-Circuit Serial Programming) |
PIC18LF2455-I/SO Pin Configuration
| Pin 1 | MCLR/VPP/RE3 — Master Clear (Reset) input / Programming voltage / Digital input only on port E bit 3 |
| Pin 2 | RA0/AN0 — Digital I/O port A bit 0 / Analog input channel 0 |
| Pin 3 | RA1/AN1 — Digital I/O port A bit 1 / Analog input channel 1 |
| Pin 4 | RA2/AN2/VREF- — Digital I/O port A bit 2 / Analog input channel 2 / ADC negative reference |
| Pin 5 | RA3/AN3/VREF+ — Digital I/O port A bit 3 / Analog input channel 3 / ADC positive reference |
| Pin 6 | RA4/T0CKI — Digital I/O port A bit 4 (open-drain) / Timer0 clock input |
| Pin 7 | RA5/AN4/SS — Digital I/O port A bit 5 / Analog input channel 4 / SPI slave select |
| Pin 8 | VSS — Ground reference |
| Pin 9 | OSC1/CLKI/RA7 — Oscillator crystal input / External clock input / Digital I/O port A bit 7 |
| Pin 10 | OSC2/CLKO/RA6 — Oscillator crystal output / Clock output / Digital I/O port A bit 6 |
| Pin 11 | RC0/T1OSO/T1CKI — Digital I/O port C bit 0 / Timer1 oscillator output / Timer1 clock input |
| Pin 12 | RC1/T1OSI/CCP2 — Digital I/O port C bit 1 / Timer1 oscillator input / CCP2 I/O |
| Pin 13 | RC2/CCP1 — Digital I/O port C bit 2 / CCP1 I/O |
| Pin 14 | VUSB — Internal USB 3.3V regulator output (decoupling pin) |
| Pin 15 | RC4/D-/VM — Digital I/O port C bit 4 / USB D- line / External USB transceiver VM input |
| Pin 16 | RC5/D+/VP — Digital I/O port C bit 5 / USB D+ line / External USB transceiver VP input |
| Pin 17 | RC6/TX/CK — Digital I/O port C bit 6 / EUSART TX / EUSART synchronous clock |
| Pin 18 | RC7/RX/DT — Digital I/O port C bit 7 / EUSART RX / EUSART synchronous data |
| Pin 19 | VSS — Ground reference (second pin for noise isolation) |
| Pin 20 | VDD — Positive supply voltage (2.0 V to 5.5 V) |
| Pin 21 | RB0/AN12/INT0 — Digital I/O port B bit 0 / Analog input channel 12 / External interrupt 0 |
| Pin 22 | RB1/AN10/INT1 — Digital I/O port B bit 1 / Analog input channel 10 / External interrupt 1 |
| Pin 23 | RB2/AN8/INT2 — Digital I/O port B bit 2 / Analog input channel 8 / External interrupt 2 |
| Pin 24 | RB3/AN9/CCP2 — Digital I/O port B bit 3 / Analog input channel 9 / CCP2 I/O |
| Pin 25 | RB4/AN11 — Digital I/O port B bit 4 / Analog input channel 11 (interrupt-on-change) |
| Pin 26 | RB5/AN13 — Digital I/O port B bit 5 / Analog input channel 13 (interrupt-on-change) |
| Pin 27 | RB6/PGD — Digital I/O port B bit 6 / ICSP data (interrupt-on-change) |
| Pin 28 | RB7/PGC — Digital I/O port B bit 7 / ICSP clock (interrupt-on-change) |
Typical Applications
PIC18LF2455-I/SO is suitable for 6 applications: USB HID Peripheral (Keyboard/Mouse), Battery-Powered USB Sensor Logger, Industrial LIN Bus Slave Node, USB-to-SPI/I²C Bridge Adapter, Consumer Audio USB Dongle, Educational USB Development Platform.
USB HID Peripheral (Keyboard/Mouse)
The PIC18LF2455-I/SO is well suited to USB Human Interface Devices such as keyboards, mice, and custom HID input peripherals. Its on-chip Full-Speed USB 2.0 transceiver and SIE eliminate the need for an external PHY, reducing BOM cost and PCB area to just a 15 kΩ pull-up on D+ plus ESD protection. The 48 MHz CPU delivers 10 MIPS, easily handling HID report polling at 1 kHz with room for debounce, matrix scanning, and LED control. The 24 KB Flash holds USB stacks (Microchip's MCHPFSUSB framework or MLUSB), HID report descriptors, and application firmware. At 5 V/48 MHz active, the LF2455 draws ~14 mA; in USB suspend it drops below 1 mA, helping the device meet USB suspend-current requirements.
Recommended
Battery-Powered USB Sensor Logger
The PIC18LF2455-I/SO fits battery-powered sensor data loggers that periodically connect to USB for data offload. The LF grade's 2.0 V minimum VDD allows direct connection to 2x AA cells (2.0-3.0 V) or a single Li-ion cell (3.0-4.2 V) without a boost regulator. nanoWatt sleep modes drop quiescent current to ~100 nA, enabling multi-year battery life on intermittent-sampling duty cycles. The on-chip 10-bit ADC samples up to 13 analog channels, and the 2 KB RAM buffers several hundred samples between USB transfers. When the user plugs in USB, firmware jumps to CDC class to stream data at 12 Mbit/s while charging the battery through a power-sharing circuit.
Recommended
Industrial LIN Bus Slave Node
The PIC18LF2455-I/SO's EUSART with LIN 1.3/2.0/2.1 capability makes it a strong fit for industrial LIN bus slave nodes such as body-control modules, sensor clusters, and HVAC actuators. The EUSART handles LIN break detection, automatic baud-rate synchronization, and checksum generation in hardware, offloading the host CPU. The wide 2.0-5.5 V VDD tolerates automotive 12V bus transients (with external TVS protection) and 5V regulated rails. The 24 KB Flash fits LIN state machines plus application logic, and the 2 KB RAM supports LIN frame buffers. The LF voltage range helps when designing for sleep-mode nodes drawing <100 µA quiescent current, satisfying automotive quiescent-current budgets.
Recommended
USB-to-SPI/I²C Bridge Adapter
The PIC18LF2455-I/SO can act as a low-cost USB-to-SPI or USB-to-I²C bridge, letting a host PC configure and read sensors, EEPROMs, or FPGAs over USB. The integrated Full-Speed USB plus hardware MSSP (Master Synchronous Serial Port) running up to 10 Mbit/s SPI supports high-throughput sensor streaming. CDC class firmware presents the bridge as a virtual COM port, eliminating custom driver installation. The 2 KB RAM holds multi-byte SPI frames, and the 24 KB Flash fits the USB stack plus command parser. Developers can use Microchip's USB CDC firmware framework as a starting point. The 28-SOIC package suits hand-assembled debug adapters and small production runs.
Recommended
Consumer Audio USB Dongle
The PIC18LF2455-I/SO powers low-cost consumer USB audio dongles such as headset adapters, microphone interfaces, and headphone amplifiers with volume control. The 48 MHz CPU executes USB isochronous transfers and audio sample-rate processing, while the 10-bit PWM or ECCP module drives a Class-D amplifier stage for analog audio output. The 2.0-5.5 V VDD accepts USB bus power (4.75-5.25 V) and supports direct 3.3V designs using an internal regulator. The 24 KB Flash holds USB audio class 1.0 drivers plus DSP-style volume/balance processing, and the LF variant enables battery-powered portable audio interfaces that draw from a single Li-ion cell.
Recommended
Educational USB Development Platform
The PIC18LF2455-I/SO is widely used in universities and hobbyist training kits as an introduction to USB firmware development. The 28-SOIC package fits standard 28-pin DIP adapter boards, allowing students to swap parts on breadboards and through-hole trainers without specialized SMT tools. MPLAB X IDE and the free XC8 compiler support the part with no license fees for hobbyist use. The on-chip USB eliminates the external PHY complexity, focusing learning on descriptor design, endpoint management, and interrupt-driven firmware. The LF variant's 2.0 V operation teaches low-power design techniques alongside USB fundamentals, making the platform valuable for embedded systems coursework.
Recommended
Recommended Products Summary
Engineering reference data for PIC18LF2455-I/SO — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC18LF2550-I/SO | PIC18F2455-I/SO | PIC18LF2450-I/SO | PIC18F2450-I/SO | PIC18F2550-I/SO |
|---|---|---|---|---|---|---|
| Package | 28-SOIC | 28-SOIC - same | 28-SOIC - same | 28-SOIC - same | 28-SOIC - same | 28-SOIC - same |
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Operating Voltage Range | 2.0 V to 5.5 V | 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 |
| Flash Program Memory | 24 KB | 32 KB | 24 KB | 16 KB | 16 KB | 32 KB |
| RAM | 2048 bytes | 2048 bytes | 2048 bytes | 2048 bytes | 2048 bytes | 2048 bytes |
| EEPROM | 256 bytes | 256 bytes | 256 bytes | 256 bytes | 256 bytes | 256 bytes |
| USB 2.0 Full-Speed | Yes (on-chip) | Yes (on-chip) | Yes (on-chip) | Yes (on-chip) | Yes (on-chip) | Yes (on-chip) |
| CPU Frequency (max) | 48 MHz | 48 MHz | 48 MHz | 48 MHz | 48 MHz | 48 MHz |
| Pin Count / Package | 28 / SOIC | 28 / SOIC | 28 / SOIC | 28 / SOIC | 28 / SOIC | 28 / SOIC |
Key Differentiators
- Low-voltage 2.0 V minimum VDD vs F grade's 4.2 V minimum (vs PIC18F2455-I/SO)
- Larger Flash program memory within LF family (vs PIC18LF2450-I/SO)
- Lower Flash usage fits smaller USB class stacks (vs PIC18LF2550-I/SO)
Design Notes
The LF2455-I/SO requires careful VDD decoupling: place a 100 nF ceramic capacitor as close as possible to pin 20 (VDD) and pin 19 (VSS), plus a bulk 10 µF tantalum or ceramic on the VDD rail. The VUSB pin (14) needs its own 220 nF decoupling capacitor to stabilize the internal 3.3V USB regulator. For USB bus-powered designs, add a 10 µF capacitor on the VBUS rail to handle USB inrush transients. The LF variant requires VDD ≥ 3.0 V for reliable USB transceiver operation; below 3.0 V, USB signal integrity degrades and pull-up on D+ may be insufficient. Estimate: typical active current at 48 MHz/5V is ~14 mA, dropping to ~100 nA in sleep mode.
Do not assume PIC18LF2455-I/SO is a drop-in upgrade for PIC18F2455-I/SO without verifying VDD range. The LF grade operates from 2.0 V to 5.5 V, but the F grade starts at 4.2 V - reverse-substitution (F replacing LF) fails when VDD is below 4.2 V. Also note that the LF2455 disables the internal USB voltage regulator's 3.3V output below ~3.0 V; if your design relies on VUSB as a regulated rail, you must add an external 3.3V LDO. The configuration bits (CONFIG1L) must set the oscillator mode correctly for the chosen clock source - using the internal oscillator requires FOSC = 0x4 (INTOSC).
Route USB D+ (pin 16) and D- (pin 15) as a 90 Ω differential pair matched within 1 mm, with the series 27 Ω resistors placed near the MCU pins per USB specification. Keep the 15 kΩ pull-up on D+ close to the MCU, and place ESD protection (e.g., PESD5V0S1BA) within 4 mm of the USB connector. The ICSP pins (RB6/PGD pin 27, RB7/PGC pin 28) should be routed with test-point access for in-circuit programming. Use a ground pour on the top layer under the MCU and stitch VSS pins 8 and 19 together with multiple vias to a solid ground plane.
Compliance Information
RoHS and lead-free per Microchip product page; REACH compliance declared by Microchip. Not AEC-Q100 qualified (industrial grade -I only); for automotive designs use PIC18F2455-I/SO with AEC-Q100 screening by supplier. Industrial temperature range -40C to +85C.
