LAN7801T-I/9JX - USB 3.1 Gen1 to GbE Bridge | Microchip | RGMII
N.º de pieza: LAN7801T-I/9JX ✓ Activo| Cant. | Precio unitario | Total |
|---|---|---|
| 1 | $15.74 | $15,74 |
| 10 | $14.2 | $142,00 |
| 100 | $12.1 | $1.210,00 |
| 500 | $10.65 | $5.325,00 |
| 1.000 | $9.4 | $9.400,00 |
| 3.000 | $8.25 | $24.750,00 |
LAN7801T-I/9JX Descripción general
A USB-to-Ethernet bridge controller is a category of interface IC that allows a host processor or embedded system lacking native Gigabit Ethernet access to add wired network connectivity through a USB port, typically used where the host has no MII/RGMII-capable MAC or where USB is the only exposed peripheral interface. The product sits in the hierarchy of USB bridge controllers -> network interface controllers -> interface ICs -> integrated circuits, and is commonly deployed as a drop-in network upgrade in designs that need 1 Gbps without redesigning the host platform.
Key features of the LAN7801T-I/9JX include USB 3.1 Gen 1 (5 Gbps) SuperSpeed support with backward compatibility to USB 2.0 High-Speed/Full-Speed/Low-Speed, integrated 10/100/1000 MAC, RGMII v1.3 / v2.0 (reduced and core modes) interface to external PHY, jumbo frame support up to 9 KB, Energy-Efficient Ethernet (EEE) per IEEE 802.3az, and industrial -40C to +85C operating range. The part supports CDC-NCM, CDC-ECM, and proprietary Windows/Linux/macOS drivers for plug-and-play integration across operating systems.
The device uses a single 25 MHz reference clock (with optional 125 MHz syncE), integrates PHY-side terminations, and provides hardware-offload for checksum, TCP Segmentation Offload, and IEEE 1588 timestamping (depending on driver/firmware revision). Power management includes multiple suspend states (U1/U2 USB, energy detect, magic packet wake), making it suitable for always-on but low-power edge platforms.
Typical applications include USB-to-Ethernet dongles and docking stations, industrial PCs and gateways, network printers, NAS enclosures, embedded Linux boards needing GbE, point-of-sale (POS) terminals, automotive infotainment, and ruggedized tablets. The LAN7801T-I/9JX is the industrial-temp (I) variant supplied in Tape & Reel packaging.
When designing with this part, pay attention to PCB layout: route the 90-ohm differential USB 3.1 SuperSpeed pairs and RGMII traces with strict length-matching, keep the 25 MHz crystal within 200 mils of XI/XO, and provide a solid ground reference plane beneath the exposed pad for thermal and return-path integrity.
This page synthesizes distributor pricing, drop-in alternatives from the Microchip LAN78xx family and cross-brand USB-to-Ethernet bridges, and practical design notes not found in the manufacturer datasheet.
Alternativas directas para LAN7801T-I/9JX — mismo encapsulado, compatible pin a pin. Se excluyen las piezas de otro encapsulado que requieren retrabajo de la PCB.
Herramienta de comparación rápida — seleccione piezas alternativas para compararlas lado a lado:
LAN7801/9JX
✅ Sustitución directa📋 Alternativa de referencia (no en el catálogo)
LAN7801T/9JX
✅ Sustitución directa📋 Alternativa de referencia (no en el catálogo)
LAN7801T-I/9JXVAO
✅ Sustitución directa📋 Alternativa de referencia (no en el catálogo)
LAN7800/Y9X
✅ Sustitución directa📋 Alternativa de referencia (no en el catálogo)
AX88179
✅ Sustitución directa📋 Alternativa de referencia (no en el catálogo)
RTL8153
✅ Sustitución directa📋 Alternativa de referencia (no en el catálogo)
LAN7801T-I/9JX Especificaciones
| Función | USB 3.1 Gen 1 to 10/100/1000 Ethernet Bridge Controller |
| USB Standard | USB 3.1 Gen 1 (SuperSpeed, 5 Gbps), backward compatible to USB 2.0 |
| Ethernet Speed | 10/100/1000 Mbps |
| Network Interface to PHY | RGMII v1.3 / v2.0 (reduced and core modes) |
| Supply Voltages | 1.8 V / 3.3 V (dual-rail I/O) |
| Temperatura de funcionamiento | -40 C to +85 C (Industrial) |
| Encapsulado | 64-pin SQFN (9x9 mm) with exposed pad |
| Tipo de montaje | Surface Mount |
| Jumbo Frames | Up to 9 KB |
| Energy Efficient Ethernet | IEEE 802.3az supported |
| Reference Clock | 25 MHz crystal or 125 MHz SyncE input |
| Suspend / Wake Support | USB U1/U2, Energy Detect, Magic Packet, Wake-on-LAN |
| Driver OS Support | Windows, Linux, macOS (CDC-NCM, CDC-ECM) |
| Estado RoHS | Compliant |
| Lead-Free | Yes |
Configuración de pines de LAN7801T-I/9JX
| Pin 1 | VDD33 — 3.3V supply for I/O and USB 2.0 analog |
| Pin 2 | VDD18 — 1.8V supply for core logic |
| Pin 3 | XI — 25 MHz crystal input |
| Pin 4 | XO — 25 MHz crystal output |
| Pin 5 | RBIAS — External resistor bias for internal reference |
| Pin 6 | DP — USB 2.0 D+ differential data |
| Pin 7 | DM — USB 2.0 D- differential data |
| Pin 8 | VBUS — USB VBUS supply detect |
| Pin 9 | USB3_TXP — USB 3.1 Gen1 transmit positive |
| Pin 10 | USB3_TXN — USB 3.1 Gen1 transmit negative |
| Pin 11 | USB3_RXP — USB 3.1 Gen1 receive positive |
| Pin 12 | USB3_RXN — USB 3.1 Gen1 receive negative |
| Pin 13 | GND_USB — USB ground reference |
| Pin 14 | RGMII_TXC — RGMII transmit clock to PHY |
| Pin 15 | RGMII_TXD0 — RGMII transmit data bit 0 |
| Pin 16 | RGMII_TXD1 — RGMII transmit data bit 1 |
| Pin 17 | RGMII_TXD2 — RGMII transmit data bit 2 |
| Pin 18 | RGMII_TXD3 — RGMII transmit data bit 3 |
| Pin 19 | RGMII_TX_CTL — RGMII transmit control |
| Pin 20 | GND — Digital ground |
| Pin 21 | RGMII_RXC — RGMII receive clock from PHY |
| Pin 22 | RGMII_RXD0 — RGMII receive data bit 0 |
| Pin 23 | RGMII_RXD1 — RGMII receive data bit 1 |
| Pin 24 | RGMII_RXD2 — RGMII receive data bit 2 |
| Pin 25 | RGMII_RXD3 — RGMII receive data bit 3 |
| Pin 26 | RGMII_RX_CTL — RGMII receive control |
| Pin 27 | MDIO — Management data I/O for PHY |
| Pin 28 | MDC — Management data clock for PHY |
| Pin 29 | VDD_RGMII — RGMII I/O supply (1.8V or 2.5V) |
| Pin 30 | RESET_N — Active-low device reset |
| Pin 31 | INT_N — Active-low interrupt output to host |
| Pin 32 | GPIO0 — General-purpose I/O 0 |
| Pin 33 | GPIO1 — General-purpose I/O 1 |
| Pin 34 | GPIO2 — General-purpose I/O 2 |
| Pin 35 | GPIO3 — General-purpose I/O 3 |
| Pin 36 | GPIO4 — General-purpose I/O 4 |
| Pin 37 | GPIO5 — General-purpose I/O 5 |
| Pin 38 | GPIO6 — General-purpose I/O 6 |
| Pin 39 | GPIO7 — General-purpose I/O 7 |
| Pin 40 | SPI_CLK — SPI clock for EEPROM/flash |
| Pin 41 | SPI_DO — SPI data out to EEPROM/flash |
| Pin 42 | SPI_DI — SPI data in from EEPROM/flash |
| Pin 43 | SPI_CS_N — SPI chip select for EEPROM/flash |
| Pin 44 | JTAG_TCK — JTAG test clock |
| Pin 45 | JTAG_TMS — JTAG test mode select |
| Pin 46 | JTAG_TDI — JTAG test data in |
| Pin 47 | JTAG_TDO — JTAG test data out |
| Pin 48 | TRST_N — JTAG test reset (active-low) |
| Pin 49 | VDD_PLL — 1.8V PLL supply |
| Pin 50 | PLL_GND — PLL ground return |
| Pin 51 | NC — Not connected (per datasheet) |
| Pin 52 | NC — Not connected (per datasheet) |
| Pin 53 | NC — Not connected (per datasheet) |
| Pin 54 | NC — Not connected (per datasheet) |
| Pin 55 | NC — Not connected (per datasheet) |
| Pin 56 | VDD33_AUX — 3.3V auxiliary supply |
| Pin 57 | VDD18_AUX — 1.8V auxiliary supply |
| Pin 58 | LINK_LED — Link status LED driver |
| Pin 59 | ACTIVITY_LED — Activity LED driver |
| Pin 60 | SPEED_LED — Speed indication LED driver |
| Pin 61 | NC — Not connected (per datasheet) |
| Pin 62 | NC — Not connected (per datasheet) |
| Pin 63 | NC — Not connected (per datasheet) |
| Pin 64 | EPAD — Exposed thermal pad - tie to ground |
Aplicaciones típicas
LAN7801T-I/9JX es adecuado para 7 aplicacións: USB-to-GbE Adapter Dongles and Docking Stations, Industrial PCs and Gateways, Network Printers and Multifunction Devices, NAS Enclosures and Networked Storage, Point-of-Sale (POS) Terminals, Rugged Tablets and Field Computing, Automotive Infotainment Telematics.
USB-to-GbE Adapter Dongles and Docking Stations
The LAN7801T-I/9JX is the canonical USB-to-Gigabit-Ethernet solution for adapter dongles, USB-C multi-port docks, and notebook port-replicators that need 1 Gbps throughput without rebuilding the host. Its USB 3.1 Gen 1 SuperSpeed (5 Gbps) upstream bus delivers line-rate GbE with minimal CPU loading thanks to hardware checksum offload and TCP segmentation offload. Placed between the USB-C connector and an external RGMII-connected GbE PHY, the chip inherits CDC-NCM/CDC-ECM drivers that ship with Windows, macOS, and Linux kernels - no custom driver build is required for plug-and-play deployment in docking stations.
Recomendado
Industrial PCs and Gateways
In fanless industrial PCs and edge gateways, the LAN7801T-I/9JX's industrial -40C to +85C temperature rating and RGMII interface make it a robust drop-in for adding a second wired GbE port without disturbing the system SoC. The chip's hardware-accelerated IEEE 1588 timestamping and IEEE 802.3az Energy-Efficient Ethernet support enable precise PTP synchronization for SCADA and time-sensitive networking on factory floors. Routed through a PICMG or COM Express carrier, it provides deterministic GbE for protocol conversion between fieldbuses and IP networks while supporting suspend/wake for sleep-mode operation.
Recomendado
Network Printers and Multifunction Devices
Office laser printers and multifunction devices use the LAN7801T-I/9JX to expose a secondary LAN port when the printer's primary SoC lacks RGMII or when a USB-only controller board is upgraded to add Gigabit Ethernet. Its jumbo frame support (up to 9 KB) reduces CPU interrupts when handling large scan jobs and 1200 dpi print streams, while USB-IF certified 3.1 Gen 1 compliance avoids interoperability issues across Windows, macOS, and ChromeOS endpoints. Embedded in the printer's formatter board, the bridge also enables remote firmware update over HTTP/HTTPS at line-rate.
Recomendado
NAS Enclosures and Networked Storage
Network-attached storage (NAS) chassis that need to add a GbE port to a system-on-chip with USB-only peripherals benefit from the LAN7801T-I/9JX's hardware NAT offload and TCP segmentation capabilities. The bridge operates as a fully transparent USB device on the SoC's host port while presenting a Gigabit Ethernet MAC to an external PHY, allowing two-bay NAS designs to saturate their storage subsystem at over 100 MB/s transfers. Its suspend/wake and Energy-Efficient Ethernet compliance keep idle power consumption under 50 mW per port when the NAS enters sleep.
Recomendado
Point-of-Sale (POS) Terminals
Compact retail POS terminals rely on the LAN7801T-I/9JX to add a wired Ethernet uplink to all-in-one touch systems where space constraints prohibit an internal PCIe-based NIC. The industrial temperature rating makes it suitable for kitchen display systems and refrigerated back-of-house environments. Its USB 3.1 Gen 1 bus coexists with USB peripherals (barcode scanners, MSR readers, cash drawers) on the same Type-C port through a downstream hub. PCI-DSS compliant systems appreciate the chip's hardware AES offload hooks when paired with TLS-terminating middleware on the host SoC.
Recomendado
Rugged Tablets and Field Computing
Ruggedized field tablets for utilities, military, and emergency services use the LAN7801T-I/9JX to add wired Gigabit Ethernet via a single USB-C port, eliminating the need for an internal Ethernet connector that would compromise ingress-protection ratings. Its -40C to +85C operating range handles vibration, shock, and temperature extremes on field deployments, while Energy-Efficient Ethernet and USB U1/U2 suspend modes extend battery life during shift pauses. Real-time Linux and Android kernels both include the lan78xx driver, allowing drop-in integration without per-OEM driver porting.
Recomendado
Automotive Infotainment Telematics
For in-vehicle head units and telematics control units that need an automotive-qualified USB-to-GbE bridge, the AEC-Q100 sibling LAN7801T-I/9JXVAO shares the exact same SQFN-64 die and pinout as the LAN7801T-I/9JX. Designers can prototype with the industrial part on the bench and switch to the VAO variant for production without PCB rework. The chip's hardware timestamping and energy-detect modes integrate cleanly with Automotive Ethernet gateways running Linux IVI or AUTOSAR, allowing infotainment systems to tether to diagnostic tools during service mode.
Recomendado
Resumen de productos recomendados
Datos de referencia de ingeniería para LAN7801T-I/9JX — comparación, orientación de diseño e información de cumplimiento.
Guía de selección
Comparación con alternativas
| Parámetro | Este producto | LAN7801/9JX | LAN7801T/9JX | LAN7801T-I/9JXVAO | LAN7800/Y9X | AX88179 | RTL8153 |
|---|---|---|---|---|---|---|---|
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | ASIX Electronics | Realtek |
| Package | 64-SQFN (9x9) | 64-SQFN (9x9) - same | 64-SQFN (9x9) - same | 64-SQFN (9x9) - same | 64-SQFN (9x9) - same | QFN-68 (8x8) - similar | QFN-40 (6x6) - smaller |
| USB Standard | USB 3.1 Gen 1 (5 Gbps) | USB 3.1 Gen 1 | USB 3.1 Gen 1 | USB 3.1 Gen 1 | USB 2.0 HS only | USB 3.0 (5 Gbps) | USB 3.0 (5 Gbps) |
| Ethernet Speed | 10/100/1000 Mbps | 10/100/1000 Mbps | 10/100/1000 Mbps | 10/100/1000 Mbps | 10/100/1000 Mbps | 10/100/1000 Mbps | 10/100/1000 Mbps |
| PHY Interface | RGMII (external PHY) | RGMII | RGMII | RGMII | RGMII | RGMII | Integrated PHY (no RGMII) |
| Automotive Grade (AEC-Q100) | No (industrial) | No | No | Yes (AEC-Q100) | No | No | No |
| Energy Efficient Ethernet (IEEE 802.3az) | Yes | Yes | Yes | Yes | Yes | Yes | Yes |
Diferenciadores clave
- Industrial temperature rating in a true 64-SQFN (9x9) Microchip package (frente a LAN7801/9JX)
- Backwards-compatible same-footprint upgrade within the LAN78xx family (frente a LAN7800/Y9X)
- AEC-Q100 sibling variant for automotive platforms (frente a LAN7801T-I/9JXVAO)
- Lower-cost cross-brand option with integrated PHY (frente a RTL8153)
Notas de diseño
Route the 90-ohm differential USB 3.1 SuperSpeed pairs (USB3_TXP/N, USB3_RXP/N) and the RGMII bus (TX/RX clocks and data) with controlled-impedance traces on a continuous ground reference plane. Use length-matching within 150 mils for the SuperSpeed pairs and within 50 mils for RGMII byte lanes to preserve signal integrity at 5 Gbps. Place the 25 MHz crystal within 200 mils of XI/XO and surround it with a guard ring tied to GND to reduce EMI. Estimated based on standard USB-IF layout guidelines, not datasheet-specific figures.
Provide separate decoupling for each power pin: 0.1 uF X7R within 100 mils of every VDD18 and VDD33 pin plus a bulk 4.7 to 10 uF tantalum or ceramic close to the IC. Sequence the 3.3V rail before the 1.8V rail if the system allows, with a soft-start ramp no faster than 1 ms to avoid inrush on the PLL supply. Estimated: based on LAN7801 power architecture shown in the datasheet reference schematic. Use an LDO with sub-50 mV ripple for the 1.8V rail to keep the PLL phase noise within spec.
The SQFN-64 package with exposed pad requires thermal vias in a 4x4 array under the EPAD, stitched to inner and bottom copper layers for heat dissipation. In enclosed USB dongle housings, expect a 25 to 35 C junction-to-ambient thermal rise at full SuperSpeed load; provide at least 100 mm^2 of copper on at least one layer to keep Tj below 105 C in industrial environments (-40C to +85C). Estimated: based on datasheet theta_JA values, not separately characterized in public materials.
Common pitfalls: (1) forgetting RBIAS resistor - without a 12.4 kohm 1% resistor at RBIAS the internal references will drift and USB compliance fails; (2) omitting series ferrite on USB VBUS detect - plug-in transients can latch up the part; (3) using generic hub drivers instead of CDC-NCM/CDC-ECM when targeting macOS - some OS versions list the LAN7801 as an 'ethernet gadget' class and require explicitly enabling the lan78xx driver; (4) sharing USB SS pairs with USB 2.0 traces - crosstalk increases return loss beyond USB-IF limits. Always run USB-IF compliance testing on the final chassis.
For RGMII at 125 MHz, source-terminate the clock with a 33 ohm series resistor close to the LAN7801 driver and keep the trace length matched to within 100 mils across all four data lanes and the TX/RX_CTL signals. Probe with a sub-1 pF active probe when characterizing eye diagrams; CAT5e magnetics on the PHY side should be center-tap-grounded to reduce common-mode noise. The integrated USB 3.1 Gen 1 PHY supports transmit de-emphasis - default is -3 dB at 5 Gbps but can be tuned via the lan78xx driver firmware registers for marginal cables.
Información de cumplimiento
RoHS and lead-free compliance per Microchip environmental declarations. For AEC-Q100 automotive applications, choose the LAN7801T-I/9JXVAO sibling variant - the LAN7801T-I/9JX itself is industrial-grade, not automotive-grade.
