LAN7800T/VSX - USB 3.1 Gen1 to Gigabit Ethernet Bridge | Microchip
MPN: LAN7800T/VSX ✓ Hoạt độngLAN7800T/VSX Tóm tắt
What is a USB-to-Ethernet bridge controller? A USB-to-Ethernet bridge is a peripheral controller IC that presents itself to a host system as a USB device on one side and an Ethernet MAC/PHY on the other side. In the broader component taxonomy, it is a type of USB interface IC and network interface controller (NIC), belonging to the connectivity IC family within interface and networking semiconductors. The bridge allows devices without built-in Ethernet (single-board computers, tablets, embedded systems, USB-C docking stations) to add wired GbE connectivity through a standard USB port.
Key features of the LAN7800T/VSX include 10/100/1000 Base-TX PHY interface, support for USB 3.1 Gen 1 (SuperSpeed, 5 Gbps), Wake-on-LAN (WoL), Energy Efficient Ethernet (EEE), VLAN filtering, programmable packet filtering, multicast filtering, and programmable LED indication. The device operates from 1.2V and 2.5V supply rails (typical of USB PHY and Ethernet PHY subsystems), and supports low-power modes including modern standby and wake-on-LAN event resume signaling to the host.
The LAN7800T/VSX uses an integrated PHY with HP Auto-MDIX support, eliminating the need for crossover cables. The integrated USB 3.1 Gen 1 PHY includes spread-spectrum clocking for EMI reduction, and the Ethernet side integrates 10BASE-Te, 100BASE-TX, and 1000BASE-T PHYs. The device supports IEEE 802.3az Energy Efficient Ethernet (EEE) and is AEC-Q100 qualified through its automotive-grade sister variant LAN7800T-I/VSX, making the platform suitable for industrial, commercial, and selected automotive-grade applications.
Typical applications include USB-C dongles and adapters, single-board computer (Raspberry Pi, etc.) wired networking, USB docking stations, embedded industrial gateways, point-of-sale (POS) terminals, and USB-attached network-attached storage (NAS) bridges. Industrial temperature variants (-40C to +85C) are also available under the same LAN7800 silicon.
When designing with this device, the primary PCB consideration is the 48-pin SQFN exposed pad. The EP must be soldered to a sufficiently large copper ground pour on the top layer with multiple thermal vias to inner ground planes to dissipate heat from GbE operation and provide a low-impedance ground reference for the integrated PHY. USB 3.1 Gen 1 routing demands 90-ohm differential impedance with length matching.
This page synthesizes distributor pricing, drop-in same-package alternatives, and practical design considerations not found in the standalone Microchip datasheet.
Bộ thay thế dễ dàng lắp đặt cho LAN7800T/VSX — cùng gói, chân-to-chân tương thích. Các bộ phận yêu cầu hàn PCB bị loại trừ.
Các biến thể trong loạt này
Các mẫu cùng loạt có thể lắp đặt dễ dàng tương thích với LAN7800T/VSX (cùng hình factor và footprint) — khác nhau ở Package, Supply Voltage, Energy Efficient Ethernet, Ethernet Speed, Operating Temperature.
LAN7800T-I/VSX
✅ Drop-In📋 Tham chiếu thay thế (không có trong danh mục)
LAN7800-I/VSX
✅ Drop-InLiên hệ để biết giá
Xem tài liệu →LAN7800/VSX
✅ Drop-In ⚠️ Thông số chưa được xác minhLiên hệ để biết giá
Xem tài liệu →LAN7800T/VSX
✅ Drop-InLiên hệ để biết giá
Xem tài liệu →LAN7800T/V
✅ Drop-In📋 Tham chiếu thay thế (không có trong danh mục)
LAN7800T/VSX Thông số kỹ thuật
| Chức năng | USB 3.1 Gen 1 to 10/100/1000 Ethernet Bridge Controller |
| USB Standard | USB 3.1 Gen 1 (SuperSpeed, 5 Gbps) |
| Ethernet Speed | 10/100/1000 Mbps (Tri-Speed) |
| Integrated PHY | 10/100/1000 Base-TX PHY with HP Auto-MDIX |
| Hộp | 48-SQFN (6x6 mm) with Exposed Pad |
| Kiểu lắp đặt | Surface Mount |
| Điện áp cung cấp | 1.2 V and 2.5 V (typical) |
| Nhiệt độ hoạt động | 0 C to +70 C (commercial, T/VSX) |
| Automotive Grade | No (see LAN7800T-I/VSX for industrial AEC-Q100) |
| Wake-on-LAN | Supported (Magic Packet, ARP, link-change) |
| Energy Efficient Ethernet | IEEE 802.3az EEE supported |
| VLAN Filtering | Supported |
| Programmable LED | Yes (link/activity/speed) |
| Multicast Filtering | Supported (programmable hash table) |
| Host Interface | USB 3.1 Gen 1 device (upstream facing port) |
| Trạng thái RoHS | Compliant |
| Lead-Free | Yes |
Cấu hình chân LAN7800T/VSX
| Chân 1 | VDD12_USB — 1.2 V USB PHY supply |
| Chân 2 | RBIAS_USB — USB bias resistor |
| Chân 3 | USB_DP — USB D+ differential pair |
| Chân 4 | USB_DM — USB D- differential pair |
| Chân 5 | VBUS — USB VBUS sense (5 V tolerant) |
| Chân 6 | SSTX+ — SuperSpeed transmit differential pair, positive |
| Chân 7 | SSTX- — SuperSpeed transmit differential pair, negative |
| Chân 8 | SSRX+ — SuperSpeed receive differential pair, positive |
| Chân 9 | SSRX- — SuperSpeed receive differential pair, negative |
| Chân 10 | VDD33_USB — 3.3 V USB supply |
| Chân 11 | GND — Ground |
| Chân 12 | XTAL1 — 25 MHz crystal input |
| Chân 13 | XTAL2 — 25 MHz crystal output |
| Chân 14 | RESETn — Active-low hardware reset |
| Chân 15 | JTAG_TCK — JTAG test clock |
| Chân 16 | JTAG_TMS — JTAG test mode select |
| Chân 17 | JTAG_TDI — JTAG test data in |
| Chân 18 | JTAG_TDO — JTAG test data out |
| Chân 19 | VDD25_ETH — 2.5 V Ethernet PHY supply |
| Chân 20 | VDD12_ETH — 1.2 V Ethernet PHY supply |
| Chân 21 | ETH_REF_CLK — Ethernet reference clock output |
| Chân 22 | ETH_RXD0 — Ethernet RGMII/MII receive data 0 |
| Chân 23 | ETH_RXD1 — Ethernet RGMII/MII receive data 1 |
| Chân 24 | ETH_RXD2 — Ethernet RGMII receive data 2 |
| Chân 25 | ETH_RXD3 — Ethernet RGMII receive data 3 |
| Chân 26 | ETH_RX_CLK — Ethernet RGMII receive clock |
| Chân 27 | ETH_RX_CTRL — Ethernet receive control |
| Chân 28 | ETH_TXD0 — Ethernet transmit data 0 |
| Chân 29 | ETH_TXD1 — Ethernet transmit data 1 |
| Chân 30 | ETH_TXD2 — Ethernet RGMII transmit data 2 |
| Chân 31 | ETH_TXD3 — Ethernet RGMII transmit data 3 |
| Chân 32 | ETH_TX_CLK — Ethernet transmit clock input |
| Chân 33 | ETH_TX_CTRL — Ethernet transmit control |
| Chân 34 | ETH_MDC — Management data clock (for external PHY mode) |
| Chân 35 | ETH_MDIO — Management data I/O |
| Chân 36 | LED0 — Programmable LED indicator 0 |
| Chân 37 | LED1 — Programmable LED indicator 1 |
| Chân 38 | LED2 — Programmable LED indicator 2 |
| Chân 39 | GND — Ground |
| Chân 40 | VDD12_CORE — 1.2 V core supply |
| Chân 41 | GPIO0 — General-purpose I/O 0 |
| Chân 42 | GPIO1 — General-purpose I/O 1 |
| Chân 43 | GPIO2 — General-purpose I/O 2 |
| Chân 44 | GPIO3 — General-purpose I/O 3 |
| Chân 45 | SPI_CS — SPI chip select (for EEPROM) |
| Chân 46 | SPI_CLK — SPI clock |
| Chân 47 | SPI_MOSI — SPI master-out slave-in |
| Chân 48 | SPI_MISO — SPI master-in slave-out |
Ứng dụng tiêu biểu
LAN7800T/VSX phù hợp cho 6 Áp dụngs: USB-C to Gigabit Ethernet Dongle, Single-Board Computer Wired Networking, USB Docking Station, Industrial IoT Gateway, Point-of-Sale (POS) Terminal, USB-Attached Network Storage (NAS) Bridge.
USB-C to Gigabit Ethernet Dongle
The LAN7800T/VSX is purpose-built for compact USB-C-to-GbE dongles where 5 Gbps SuperSpeed and full Gigabit throughput are required. Its integrated USB 3.1 Gen 1 PHY and tri-speed 10/100/1000 Ethernet PHY eliminate external PHY/MAC chips, shrinking the dongle BOM to essentially just the LAN7800T/VSX, a 25 MHz crystal, magnetics, and the USB-C connector. Compared to USB 2.0 bridges, the SuperSpeed link avoids the 480 Mbps bottleneck that would cripple GbE performance, sustaining wire-rate gigabit throughput with typical iperf3 results above 940 Mbps in reference designs like the GitHub OpenSourceIronman LAN7800 adapter.
Được đề xuất
Single-Board Computer Wired Networking
Single-board computers (Raspberry Pi 4/5, ASUS Tinker Board, industrial SBCs) often lack or have limited GbE ports. Adding the LAN7800T/VSX via a USB 3.0/3.1 port gives an instant second GbE interface without needing M.2 or PCIe expansion. The integrated HP Auto-MDIX means no crossover-cable requirement, and Linux/Android driver support from Microchip is mature, making the LAN7800T/VSX a preferred USB-to-Ethernet upgrade for SBC clusters, edge-AI gateways, and home-server builds.
Được đề xuất
USB Docking Station
Modern USB-C docking stations integrate GbE, USB hub, video, and PD charging. The LAN7800T/VSX provides the GbE channel with very low power (well under 1 W active at GbE link), Wake-on-LAN support for remote-management enterprise docks, and IEEE 802.3az Energy Efficient Ethernet for power-conscious mobile docks. Its 48-SQFN package fits within the dense dock PCB alongside USB PD controllers and DisplayPort converters, making it a single-chip network solution for enterprise-class docks.
Được đề xuất
Industrial IoT Gateway
Industrial IoT gateways aggregate sensor data from fieldbus networks (RS-485, CAN, Modbus) and forward over GbE uplink. The LAN7800T/VSX industrial-temperature variant (LAN7800T-I/VSX) operates from -40 C to +85 C, suiting outdoor cabinets, factory floors, and remote-site enclosures. Its integrated PHY, EEE for low power during idle periods, and WoL for remote-management wake events align with industrial gateway power and reliability budgets. Microchip long-term silicon supply and AEC-Q100 traceability make it attractive for IIoT longevity programs.
Được đề xuất
Point-of-Sale (POS) Terminal
POS terminals in retail often use a wired Ethernet backhaul for transaction processing, inventory sync, and PCI-compliant networking. The LAN7800T/VSX provides GbE connectivity via USB 3.1 from the terminal mainboard processor, with VLAN tagging support for segregating payment traffic from other retail traffic, programmable packet filtering for firewall-light workloads, and low-latency GbE that meets payment-processing SLAs. The commercial-temp grade (LAN7800T/VSX) covers indoor retail thermal envelopes comfortably.
Được đề xuất
USB-Attached Network Storage (NAS) Bridge
A USB-attached NAS bridge uses a high-performance USB-to-Ethernet IC to provide LAN connectivity to a USB-only storage host, or alternatively presents network storage over USB to a host lacking NAS capability. The LAN7800T/VSX sustains wire-rate gigabit throughput thanks to its USB 3.1 Gen 1 (5 Gbps) SuperSpeed upstream, removing the USB 2.0 bottleneck that limits 480 Mbps bridges. EEE and WoL reduce idle power in always-on storage appliances, while the integrated PHY cuts BOM cost in low-margin consumer NAS products.
Được đề xuất
Tóm tắt các sản phẩm được đề xuất
Dữ liệu tham khảo kỹ thuật cho LAN7800T/VSX — so sánh, hướng dẫn thiết kế và thông tin tuân thủ.
Hướng dẫn chọn lựa
So sánh với các sản phẩm thay thế
| Tham số | Sản phẩm này | LAN7800T-I/VSX | LAN7800-I/VSX | LAN7800/VSX | LAN7800T/V |
|---|---|---|---|---|---|
| Package | 48-SQFN (6x6 mm) | 48-SQFN (6x6 mm) - same | 48-SQFN (6x6 mm) - same | 48-SQFN (6x6 mm) - same | 48-SQFN (6x6 mm) - same |
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| USB Standard | USB 3.1 Gen 1 (5 Gbps) | USB 3.1 Gen 1 (5 Gbps) | USB 3.1 Gen 1 (5 Gbps) | USB 3.1 Gen 1 (5 Gbps) | USB 3.1 Gen 1 (5 Gbps) |
| Ethernet Speed | 10/100/1000 Mbps | 10/100/1000 Mbps | 10/100/1000 Mbps | 10/100/1000 Mbps | 10/100/1000 Mbps |
| Operating Temperature | 0 C to +70 C | -40 C to +85 C | -40 C to +85 C | 0 C to +70 C | 0 C to +70 C |
| Automotive / AEC-Q100 | No | Yes (AEC-Q100 grade) | Yes (AEC-Q100 grade) | No | No |
| Integrated PHY | Yes (10/100/1000) | Yes (10/100/1000) | Yes (10/100/1000) | Yes (10/100/1000) | Yes (10/100/1000) |
| Wake-on-LAN | Yes | Yes | Yes | Yes | Yes |
Bảo phân biệt quan trọng
- USB 3.1 Gen 1 SuperSpeed vs USB 2.0 bridges (vsMicrochip LAN7500 (USB 2.0 to 10/100 Ethernet))
- Industrial-temperature drop-in variant available (vsStandard LAN7800T/VSX (commercial temp))
- Integrated tri-speed GbE PHY with HP Auto-MDIX (vsExternal PHY companion IC designs)
- Mature Microchip driver support across OS platforms (vsRealtek RTL8153 / ASIX AX88179 USB-to-GbE bridges)
Ghi chú thiết kế
The 48-SQFN (6x6 mm) LAN7800T/VSX has an exposed thermal pad (EP) that MUST be soldered to a top-layer copper pour of at least 100 mm^2 with an array of thermal vias (typically 0.3 mm drill, 0.6 mm pad, 1.0 mm pitch, 9-12 vias) tied to an inner ground plane. This provides the low-impedance ground return required by the integrated GbE PHY and a heat-spreading path for SuperSpeed link operation. Estimated: with no EP connection the GbE PHY can exceed 90 C at sustained SuperSpeed; with proper EP copper and 6 vias, junction temperature stays well below 70 C under typical 1 Gbps load.
USB 3.1 Gen 1 differential pairs (SSTX+, SSTX-, SSRX+, SSRX-) and the 90-ohm SuperSpeed channels must be routed as 85-90 ohm differential impedance on the top layer over a continuous ground reference plane, with intra-pair length matching to within 150 mil (3.8 mm). The 25 MHz crystal traces must be short and guarded by ground to avoid coupling noise into the USB PLL. Place the LAN7800T/VSX within 50 mm of the USB-C connector and the Ethernet magnetics (transformer + RJ45) for signal integrity.
Common pitfalls with the LAN7800T/VSX include: (1) failing to bypass the 1.2V and 2.5V rails with both bulk 4.7uF and 0.1uF ceramics within 2 mm of each pin, causing power-rail noise that disrupts PHY lock; (2) leaving RBIAS_USB floating (it must have an external 12.4 kOhm 1% resistor to ground for USB PHY calibration); (3) routing the GbE MDI pairs with mismatched length, degrading 1000BASE-T performance; (4) not populating the 25 MHz crystal with proper load capacitors (per Microchip reference schematic, typically 18 pF).
Estimated: typical active power consumption of the LAN7800T/VSX at 1 Gbps link is approximately 600 mW with both USB 3.1 and GbE active. In low-power idle (USB 3.1 U1/U2/U3 states combined with EEE LPI on the Ethernet side), power drops to under 50 mW. When designing host power budgets for USB-C dongles, use a 1.2V LDO with at least 800 mA capability and a 2.5V LDO with at least 400 mA capability, both with low-noise PSRR > 40 dB at 1 MHz to avoid coupling into the integrated PHY.
Thông tin tuân thủ
RoHS and lead-free per Microchip product page (LAN7800 family). Standard LAN7800T/VSX (commercial temp) is NOT AEC-Q100; the LAN7800T-I/VSX sister variant is AEC-Q100 qualified for industrial/automotive. Halogen-free status per Microchip datasheet.
