PIC18LF4550-I/ML - 8-bit USB MCU, 32KB Flash, 44-QFN | Microchip
N.º de pieza: PIC18LF4550-I/ML ✓ Activo| Cant. | Precio unitario | Total |
|---|---|---|
| 1 | $8.43 | $8,43 |
| 10 | $7.59 | $75,90 |
| 100 | $6.75 | $675,00 |
| 500 | $6.08 | $3.040,00 |
| 1.000 | $5.4 | $5.400,00 |
PIC18LF4550-I/ML Descripción general
An 8-bit microcontroller (MCU) is a programmable processor that combines a CPU, RAM, non-volatile program memory, and peripheral interfaces on a single silicon die. The PIC18 family belongs to Microchip's enhanced mid-range 8-bit architecture and occupies the hierarchical niche of microcontroller -> embedded processor -> semiconductor. The 'LF' family variant extends the legacy PIC18F4550 lineage into low-voltage applications, while the 'I' suffix denotes the industrial operating-temperature grade of -40C to +85C. The /ML package suffix designates the 44-lead QFN.
Key specifications include 32KB Flash (16K x 16 words), 2048 bytes of SRAM, 256 bytes of EEPROM, 35 digital I/O pins, and 13 ADC channels at 10-bit resolution. The integrated Full-Speed USB 2.0 controller supports 12 Mbps operation with on-chip transceivers, internal pull-up resistors, and clock recovery - eliminating external USB components. The instruction set is optimized for C-compiled code with hardware multiply and a hardware stack of 31 levels.
Typical applications include USB peripherals (HID, CDC, custom class devices), industrial control interfaces, sensor data acquisition nodes, embedded education platforms, and hobbyist projects where the PIC18F4550 has a long legacy footprint. The wide voltage range allows direct 3.3V or 5V operation from battery or bus-powered rails, and the QFN package enables compact PCB layouts where lead inductance of PDIP/TQFP would otherwise limit signal integrity.
When designing with this device, ensure the exposed thermal pad is soldered to a sufficient copper pour to meet theta_JA thermal targets. The 48 MHz internal oscillator accuracy may require calibration or external crystal for timing-critical USB applications; use the internal USB PLL only after configuring the appropriate OSCCON and CONFIG bits as documented in the manufacturer datasheet.
Alternativas directas para PIC18LF4550-I/ML — mismo encapsulado, compatible pin a pin. Se excluyen las piezas de otro encapsulado que requieren retrabajo de la PCB.
Variantes de esta serie
Modelos de la misma serie compatibles directamente con PIC18LF4550-I/ML (mismo factor de forma y huella) — difiere en Package, Core Architecture, Operating Temperature, Timers, ADC.
Herramienta de comparación rápida — seleccione piezas alternativas para compararlas lado a lado:
PIC18LF4550T-I/ML
✅ Sustitución directa✓ En stock
$3.28 / unidad
Ver hoja de datos →PIC18F4550-I/ML
✅ Sustitución directa📋 Alternativa de referencia (no en el catálogo)
PIC18LF4550-I/P
✅ Sustitución directa📋 Alternativa de referencia (no en el catálogo)
PIC18LF4553-I/ML
✅ Sustitución directa✓ En stock
$5.1 / unidad
Ver hoja de datos →PIC18LF4455-I/ML
✅ Sustitución directa✓ En stock
$3 / unidad
Ver hoja de datos →PIC18LF2550T-I/SO
✅ Sustitución directa✓ En stock
$5.1 / unidad
Ver hoja de datos →PIC18LF4550-I/ML Valores máximos y características eléctricas
| Core Architecture | PIC18 8-bit RISC (Enhanced Mid-Range) |
| Program Memory (Flash) | 32 KB (16K x 16 words) |
| SRAM | 2048 bytes |
| EEPROM | 256 bytes |
| Maximum CPU Speed | 48 MHz (12 MIPS) |
| Operating Voltage Range | 2.0 V to 5.5 V |
| Rango de temperatura de funcionamiento | -40 C to +85 C (Industrial, 'I' suffix) |
| Digital I/O Pins | 35 |
| ADC | 10-bit, up to 13 input channels |
| USB Controller | Full-Speed USB 2.0 (12 Mbps) with on-chip transceiver |
| Timers | 4 (Timer0/1/2/3) |
| Capture/Compare/PWM | 1 CCP + 1 ECCP |
| Communication Interfaces | USB 2.0 FS, 1x USART, 1x MSSP (SPI/I2C) |
| Encapsulado | 44-pin QFN (8x8 mm) with Exposed Pad, /ML |
| Tipo de montaje | Surface Mount |
| Package Material | Pb-free / Matte Tin finish |
| Estado RoHS | Compliant |
Configuración de pines de PIC18LF4550-I/ML
| Pin 1 | MCLR/VPP/RE3 — Master Clear (reset) input / Programming voltage / Digital input RE3 |
| 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 — Digital I/O RA4 / Timer0 clock input |
| Pin 7 | RA5/AN4/SS — Digital I/O RA5 / Analog input AN4 / SPI slave select |
| Pin 8 | RE0/RD — Digital I/O RE0 / Parallel port RD |
| Pin 9 | RE1/WR — Digital I/O RE1 / Parallel port WR |
| Pin 10 | D+ — USB data plus line (Full-Speed) |
| Pin 11 | D- — USB data minus line (Full-Speed) |
| Pin 12 | VUSB — USB internal 3.3V regulator output (decouple with cap) |
| Pin 13 | OSC1/CLKI — Crystal oscillator input / External clock input |
| Pin 14 | OSC2/CLKO — Crystal oscillator output / Clock output |
| Pin 15 | RC0/T1OSO — Digital I/O RC0 / Timer1 oscillator output |
| Pin 16 | RC1/T1OSI — Digital I/O RC1 / Timer1 oscillator input |
| Pin 17 | RC2/CCP1 — Digital I/O RC2 / Capture/Compare/PWM 1 |
| Pin 18 | VSS — Ground reference |
| Pin 19 | VDD — Positive logic supply voltage (2.0V to 5.5V) |
| Pin 20 | VBUS — USB bus voltage sense input |
| Pin 21 | RC4 — Digital I/O RC4 |
| Pin 22 | RC5 — Digital I/O RC5 |
| Pin 23 | RC6/TX — Digital I/O RC6 / USART asynchronous transmit |
| Pin 24 | RC7/RX — Digital I/O RC7 / USART asynchronous receive |
| Pin 25 | RD0 — Digital I/O RD0 |
| Pin 26 | RD1 — Digital I/O RD1 |
| Pin 27 | RD2 — Digital I/O RD2 |
| Pin 28 | RD3 — Digital I/O RD3 |
| Pin 29 | RD4 — Digital I/O RD4 |
| Pin 30 | RD5 — Digital I/O RD5 |
| Pin 31 | RD6 — Digital I/O RD6 |
| Pin 32 | RD7 — Digital I/O RD7 |
| Pin 33 | RB0/AN12/INT0 — Digital I/O RB0 / Analog input AN12 / External interrupt 0 |
| Pin 34 | RB1/AN10/INT1 — Digital I/O RB1 / Analog input AN10 / External interrupt 1 |
| Pin 35 | RB2/AN8/INT2 — Digital I/O RB2 / Analog input AN8 / External interrupt 2 |
| Pin 36 | RB3/AN9/CCP2 — Digital I/O RB3 / Analog input AN9 / Capture/Compare/PWM 2 |
| Pin 37 | RB4/AN11 — Digital I/O RB4 / Analog input AN11 |
| Pin 38 | RB5/AN13 — Digital I/O RB5 / Analog input AN13 |
| Pin 39 | RB6/PGC — Digital I/O RB6 / In-circuit debugger clock |
| Pin 40 | RB7/PGD — Digital I/O RB7 / In-circuit debugger data |
| Pin 41 | RE2/CS — Digital I/O RE2 / Parallel port chip select |
| Pin 42 | VSS — Ground reference |
| Pin 43 | VDD — Positive logic supply voltage (2.0V to 5.5V) |
| Pin 44 | EP — Exposed thermal pad - must be soldered to ground plane |
Aplicaciones típicas
PIC18LF4550-I/ML es adecuado para 6 aplicacións: USB HID Peripherals, USB CDC Virtual COM Port, Industrial Sensor Data Acquisition, Educational Development Platform, Custom USB Class Devices, USB Bootloader Host Adapter.
USB HID Peripherals
The PIC18LF4550-I/ML is ideal for USB Human Interface Devices (HID) such as keyboards, mice, game controllers, and custom input devices. Its integrated Full-Speed USB 2.0 transceiver with on-chip 3.3V regulator eliminates external PHY components, reducing BOM cost by $0.40-0.80 in typical designs. The 32KB Flash comfortably supports Microchip's USB HID stack and application firmware. The 48 MHz CPU speed (12 MIPS) provides sufficient throughput for HID polling rates up to 1000 Hz. The wide 2.0-5.5V supply range allows direct 3.3V or 5V bus-powered operation.
Recomendado
USB CDC Virtual COM Port
The PIC18LF4550-I/ML supports USB Communication Device Class (CDC) to implement a virtual COM port for PC-host communication, eliminating the need for USB-to-serial bridge chips like FTDI or CP2102. Its on-chip USB SIE handles protocol framing while the CPU implements the CDC state machine. The 2048 bytes of SRAM accommodate USB packet buffers and UART state, and the 256 bytes of EEPROM store CDC line-coding parameters. Compared to a bridge-chip solution, this saves $1.50-3.00 per node in industrial sensor and instrumentation designs.
Recomendado
Industrial Sensor Data Acquisition
The PIC18LF4550-I/ML fits industrial sensor nodes combining analog signal conditioning with USB data uplink. Its 10-bit ADC with up to 13 channels handles temperature, pressure, flow, and 4-20 mA sensor inputs directly. The wide 2.0-5.5V supply supports 24V industrial rails through a simple LDO. The industrial -40C to +85C temperature range meets factory automation and outdoor sensor requirements. The integrated USB enables direct laptop or panel-PC connection for sensor calibration and firmware updates in the field.
Recomendado
Educational Development Platform
The PIC18LF4550-I/ML has been a long-standing workhorse of embedded systems education due to its USB capability, ample Flash, and extensive documentation. Students can develop USB HID, CDC, custom class, and bootloader projects on the same MCU that prototypes will use in production. The 32KB Flash supports the full Microchip USB stack plus student code with margin. Hobbyist projects from audio samplers to MIDI controllers to custom keyboards all leverage the integrated USB and the rich peripheral set. The 44-QFN package teaches SMT soldering on a manageable 0.5 mm pitch.
Recomendado
Custom USB Class Devices
The PIC18LF4550-I/ML supports custom USB class devices for proprietary protocols where standard HID/CDC/Mass-Storage classes are insufficient. Its flexible endpoint configuration (up to 16 endpoints with double-buffering) and high packet throughput allow vendor-specific drivers for industrial control, test equipment, and proprietary data acquisition. The 12 MIPS CPU performance ensures bulk transfers at 12 Mbps can be sustained with full firmware processing. The exposed pad QFN package supports industrial temperature operation and minimizes PCB footprint for embedded instruments.
Recomendado
USB Bootloader Host Adapter
The PIC18LF4550-I/ML serves as a USB bootloader target or as a USB host adapter to update firmware on smaller downstream PIC MCUs. Its self-programmable Flash supports Microchip's USB bootloader, enabling field firmware updates without external programmers. The USB SIE manages the host-side protocol while the USART or SPI loads the target MCU's firmware. Compared to discrete USB-to-serial bridges, this approach adds host-controller flexibility and reduces dependency on external components, valuable for industrial asset-management and OTA-update scenarios.
Recomendado
Resumen de productos recomendados
Datos de referencia de ingeniería para PIC18LF4550-I/ML — comparación, orientación de diseño e información de cumplimiento.
Guía de selección
Comparación con alternativas
| Parámetro | Este producto | PIC18LF4550T-I/ML | PIC18F4550-I/ML | PIC18LF4553-I/ML | PIC18LF4455-I/ML |
|---|---|---|---|---|---|
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Package | 44-QFN (8x8) /ML | 44-QFN (8x8) /ML - same | 44-QFN (8x8) /ML - same | 44-QFN (8x8) /ML - same | 44-QFN (8x8) /ML - same |
| Operating Voltage Range | 2.0 V to 5.5 V (LF) | 2.0 V to 5.5 V (LF) - same | 4.2 V to 5.5 V (F) | 2.0 V to 5.5 V (LF) - same | 2.0 V to 5.5 V (LF) - same |
| Flash Program Memory | 32 KB | 32 KB - same | 32 KB - same | 24 KB | 24 KB |
| SRAM | 2048 bytes | 2048 bytes - same | 2048 bytes - same | 2048 bytes - same | 2048 bytes - same |
| CPU Speed | 48 MHz (12 MIPS) | 48 MHz - same | 48 MHz - same | 48 MHz - same | 48 MHz - same |
| USB 2.0 Support | Full-Speed (12 Mbps) with on-chip transceiver | Full-Speed USB 2.0 - same | Full-Speed USB 2.0 - same | Full-Speed USB 2.0 - same | Full-Speed USB 2.0 - same |
| Digital I/O Pins | 35 | 35 - same | 35 - same | 35 - same | 25 |
| Price (qty 1) | $8.43 USD | $7.50 USD (est. T&R variant) | $7.95 USD (DigiKey, est.) | $7.20 USD (est.) | $6.95 USD (est.) |
Diferenciadores clave
- Full-Speed USB 2.0 with on-chip transceiver and 3.3V regulator (frente a PIC18LF2550-I/SP)
- Wide 2.0V to 5.5V operating voltage (LF variant) (frente a PIC18F4550-I/ML)
- 32 KB Flash with self-programming bootloader support (frente a PIC18LF4553-I/ML)
Notas de diseño
The 44-pin QFN package features an exposed thermal pad (EP, pin 44) that MUST be soldered to the ground plane for both electrical grounding and thermal dissipation. According to the Microchip datasheet, failing to solder the EP pad increases thermal resistance by approximately 30% and can cause erratic USB behavior. Design PCB land pattern per Microchip's QFN-44 thermal land recommendation with 8-12 thermal vias connecting the EP to the opposite-side ground plane. Maintain continuous ground plane under the IC for USB signal integrity.
The internal USB 3.3V regulator output (VUSB, pin 12) requires a 220 nF decoupling capacitor and must NOT be used to source external loads above 5 mA. According to the Microchip datasheet, this regulator is designed solely for internal USB transceiver supply. For USB bus-powered applications, VBUS (pin 20) must be connected to the USB VBUS line through a divider or direct connection (per CONFIG bits) to enable bus-sensing. Always add bulk + bypass capacitance (10 uF + 100 nF) on VDD (pins 19, 43) close to the device.
Do NOT exceed 5.5V on any pin of the LF4550 - the LF variant is rated for 2.0-5.5V only; exceeding 5.5V (even briefly) can latch up the silicon. According to the Microchip datasheet, OSC1/OSC2 pins (13/14) are particularly sensitive to over-voltage when configured in external clock mode. For battery applications, ensure the supply falls within 2.0-5.5V under all load conditions, including Li-ion voltage dips below 3.0V at end-of-discharge. For USB applications, ensure firmware enables the internal USB regulator (UCON<USBEN>) before connecting to USB host.
USB D+/D- traces (pins 10, 11) must be routed as a 90-ohm differential pair with trace matching to within 150 mil. According to USB 2.0 specifications referenced in the Microchip datasheet, D+/D- should not cross any other signal traces, and should maintain a continuous ground reference plane beneath them. Series ferrite beads are recommended for EMI suppression at the USB connector. Match the characteristic impedance to 90 ohms +/- 10% by using a 4-layer PCB or tightly-coupled microstrip on a 2-layer design.
Información de cumplimiento
RoHS compliant and lead-free per Microchip product page. Not AEC-Q100 qualified - choose PIC18F4550-I/ML automotive grade for automotive applications. Halogen-free per Microchip package specifications.
