LAN7800-I/VSX - USB 3.1 Gen 1 to Gigabit Ethernet Bridge | Microchip
部品番号: LAN7800-I/VSX ✓ 生産中| 数量 | 単価 | 小計 |
|---|---|---|
| 1 | $7.95 | $7.95 |
| 10 | $7.16 | $71.60 |
| 100 | $6.36 | $636.00 |
| 500 | $5.73 | $2,865.00 |
| 1,000 | $5.1 | $5,100.00 |
| 3,000 | $4.55 | $13,650.00 |
LAN7800-I/VSX 概要
A USB to Ethernet bridge is a peripheral controller IC that translates USB transactions into Ethernet frames (and vice-versa), presenting a USB device interface to the host CPU while exposing an RJ45-style Ethernet port to the network. Modern system-on-chips often lack a wired Ethernet MAC/PHY, so an external bridge IC like the LAN7800 is required to add Gigabit LAN to embedded designs, tablets, docking stations, set-top boxes, and USB LAN dongles.
Key differentiating specifications include USB 3.1 Gen 1 (5 Gbps) SuperSpeed connectivity, integrated Gigabit Ethernet PHY supporting 10/100/1000Base-T, hardware TCP/IP checksum offload, IEEE 802.3az Energy Efficient Ethernet (EEE), and a built-in 1.2V LDO that derives core voltage from the 3.3V analog rail. The IC also supports jumbo frames up to 9 KB, VLAN tagging (IEEE 802.1Q), and Microsoft NDIS 6.2 / Linux CDC-NCM / RNDIS driver models. Power is delivered through the USB bus (bus-powered operation supported) or self-powered via an external supply.
From an architecture perspective, the LAN7800 pairs a USB 3.1 Gen 1 Physical Layer (PHY) and controller with a separate Ethernet PHY and MAC, joined by an internal DMA engine. The integrated PHY eliminates magnetics on the line side and supports HP Auto-MDIX for automatic crossover detection. The IC's hardware-offloaded TCP/IP checksums reduce host CPU loading while sustaining near-line-rate throughput.
Typical applications include notebook and tablet docking stations that add LAN connectivity through USB, USB to Gigabit Ethernet dongles for ultrabooks and MacBooks lacking RJ45 ports, set-top boxes, PVRs and streaming media adapters, embedded industrial systems requiring deterministic network connectivity, and test & measurement instruments that need a USB-attached network interface. Designers select the LAN7800 over competing USB 2.0 bridges when SuperSpeed (5 Gbps) headroom is required for true gigabit throughput.
When designing in this device, allocate generous USB 3.0 SuperSignal routing with 90-ohm differential impedance, place decoupling capacitors close to each VDD12A pin (pins 25, 30, 44), and follow the schematic checklist to avoid signal-integrity pitfalls. Use the EVB-LAN7800 reference design as the layout starting point.
This page synthesizes distributor pricing, drop-in alternatives (LAN7800/VSX commercial temp, LAN7801/9JX with RGMII support), design notes, and package-level comparisons not bundled in the manufacturer datasheet alone.
ドロップイン代替品: LAN7800-I/VSX — 同一パッケージでピン互換。PCBの作り直しが必要な異なるパッケージの部品は除外されています。
このシリーズのバリエーション
同一シリーズでドロップイン互換のモデル: LAN7800-I/VSX （同一形状・フットプリント） — 相違点: Package, Supply Voltage, Energy Efficient Ethernet, Ethernet Speed, Operating Temperature.
クイック比較ツール — 並列比較する代替部品を選択:
LAN7800/VSX
✅ ドロップイン✓ 在庫あり
価格はお問い合わせください
データシートを見る →LAN7800T/VSX
✅ ドロップイン ⚠️ 仕様未検証✓ 在庫あり
$8.1 / 個
データシートを見る →LAN7800-I/VSX 仕様
| Product Type | USB to Ethernet Bridge Controller |
| USB Interface | USB 3.1 Gen 1 (SuperSpeed, 5 Gbps) |
| Ethernet Speed | 10/100/1000 Mbps |
| Ethernet Standard | 10Base-T / 100Base-TX / 1000Base-T |
| Integrated Ethernet PHY | Yes (Gigabit) |
| MAC Interface | Internal (no external MII/RGMII) |
| パッケージ | 48-SQFN (VSX) 6x6 mm |
| 動作温度 | -40°C to +85°C (Industrial) |
| 電源電圧 | 1.8V / 3.3V (analog + digital rails) |
| Jumbo Frame Support | Up to 9 KB |
| Energy Efficient Ethernet | IEEE 802.3az compliant |
| VLAN Support | IEEE 802.1Q |
| Checksum Offload | Hardware IP/TCP/UDP checksum |
| Auto-MDIX | Yes (HP Auto-MDIX) |
| RoHS ステータス | Compliant |
LAN7800-I/VSX ピン構成
| ピン 1 | VDD33A — +3.3V analog supply |
| ピン 2 | VDD12A_PLL — +1.2V analog supply (PLL) |
| ピン 3 | VDD12A_AFE — +1.2V analog supply (AFE) |
| ピン 4 | VDD33A_USB — +3.3V analog supply (USB PHY) |
| ピン 5 | VBUS — USB VBUS detect (5V) |
| ピン 6 | USB_DP — USB D+ data line |
| ピン 7 | USB_DN — USB D- data line |
| ピン 8 | USB3_TXDP — USB 3.0 SuperSpeed TX+ (differential) |
| ピン 9 | USB3_TXDN — USB 3.0 SuperSpeed TX- (differential) |
| ピン 10 | USB3_RXDP — USB 3.0 SuperSpeed RX+ (differential) |
| ピン 11 | USB3_RXDN — USB 3.0 SuperSpeed RX- (differential) |
| ピン 12 | RESET_N — Active-low hardware reset |
| ピン 13 | GPIO0 — General purpose I/O 0 |
| ピン 14 | GPIO1 — General purpose I/O 1 |
| ピン 15 | GPIO2 — General purpose I/O 2 |
| ピン 16 | GPIO3 — General purpose I/O 3 |
| ピン 17 | GPIO4 — General purpose I/O 4 |
| ピン 18 | GPIO5 — General purpose I/O 5 |
| ピン 19 | GPIO6 — General purpose I/O 6 |
| ピン 20 | GPIO7 — General purpose I/O 7 |
| ピン 21 | VDD18_DIG — +1.8V digital supply |
| ピン 22 | VDD18A — +1.8V analog supply |
| ピン 23 | VDD33_DIG — +3.3V digital supply |
| ピン 24 | VDD12_CORE — +1.2V digital core supply (internal LDO out) |
| ピン 25 | VDD12A — +1.2V analog supply (Gigabit PHY) |
| ピン 26 | GND — Ground |
| ピン 27 | ETH_MDIAP — Ethernet MDI pair A+ |
| ピン 28 | ETH_MDIAN — Ethernet MDI pair A- |
| ピン 29 | ETH_MDIBP — Ethernet MDI pair B+ |
| ピン 30 | VDD12A — +1.2V analog supply (PHY) |
| ピン 31 | ETH_MDIBN — Ethernet MDI pair B- |
| ピン 32 | ETH_MDICP — Ethernet MDI pair C+ |
| ピン 33 | ETH_MDICN — Ethernet MDI pair C- |
| ピン 34 | ETH_MDIDP — Ethernet MDI pair D+ |
| ピン 35 | ETH_MDIDN — Ethernet MDI pair D- |
| ピン 36 | ETH_LED0 — Ethernet LED 0 (link/activity) |
| ピン 37 | ETH_LED1 — Ethernet LED 1 (speed) |
| ピン 38 | ETH_LED2 — Ethernet LED 2 (link status) |
| ピン 39 | XTAL_IN — 25 MHz crystal input |
| ピン 40 | XTAL_OUT — 25 MHz crystal output |
| ピン 41 | VDD33A_ETH — +3.3V analog supply (Ethernet PHY) |
| ピン 42 | VDD12A_ETH — +1.2V analog supply (Ethernet PHY core) |
| ピン 43 | VDD12A_PLL2 — +1.2V analog supply (Ethernet PLL) |
| ピン 44 | VDD12A — +1.2V analog supply (shared) |
| ピン 45 | NC — Not connected (per datasheet) |
| ピン 46 | NC — Not connected (per datasheet) |
| ピン 47 | NC — Not connected (per datasheet) |
| ピン 48 | NC — Not connected (per datasheet) |
| ピン 49 | EP — Exposed thermal pad - must be soldered to ground plane |
主な用途
LAN7800-I/VSX の用途: 6 件s: USB-C to Gigabit Ethernet Dongle, Notebook and Tablet Docking Station, Set-Top Box and Streaming Media Adapter, USB Port Replicator, Embedded Industrial System, Test and Measurement Instrument.
USB-C to Gigabit Ethernet Dongle
The LAN7800-I/VSX is the canonical controller for USB-C to RJ45 LAN adapters, offering USB 3.1 Gen 1 (5 Gbps) SuperSpeed and an integrated Gigabit PHY. With 940+ Mbps real-world throughput and driverless operation on Windows/Linux/macOS, it outperforms USB 2.0 (480 Mbps) bridges that cap near 300 Mbps. Its industrial temperature rating suits ruggedized travel adapters used outdoors or in industrial environments. The integrated 1.2V LDO reduces BOM and the 48-SQFN 6x6 mm package fits inside slim dongle enclosures with only a 4-layer USB 3.0 SuperSpeed stack-up required.
おすすめ
Notebook and Tablet Docking Station
Docking stations that expose wired LAN through USB rely on the LAN7800-I/VSX to provide a Gigabit Ethernet port when the host laptop or tablet has no built-in RJ45. Its HP Auto-MDIX eliminates crossover cable concerns, and 802.1Q VLAN tagging lets enterprise IT segment traffic without extra switch silicon. The industrial temperature rating ensures reliable operation in warm office environments near CPU heat exhaust or sunlit desks. Hardware TCP/IP checksum offload reduces the dock's USB host CPU overhead, sustaining wire-speed transfers for large file sync to corporate file shares.
おすすめ
Set-Top Box and Streaming Media Adapter
Set-top boxes and streaming media adapters use the LAN7800-I/VSX to add wired Gigabit Ethernet when the main processor lacks a built-in Ethernet MAC, ensuring stable 4K HDR streaming without Wi-Fi congestion. Hardware checksum offload preserves CPU cycles for video decoding, and IEEE 802.3az Energy Efficient Ethernet reduces power during idle streaming. The 48-SQFN package's small 6x6 mm footprint simplifies PCB layout under heatsinks common in STB enclosures. Industrial temperature supports hot AV cabinets.
おすすめ
USB Port Replicator
USB port replicators use the LAN7800-I/VSX to expose one or more Gigabit Ethernet ports through a single USB upstream connection, ideal for thin-client and kiosk deployments. The integrated PHY eliminates the need for a separate Ethernet PHY or magnetics on the line side, reducing BOM and PCB area. VLAN tagging and jumbo frames up to 9 KB satisfy enterprise replication workloads. The industrial temperature grade supports replicators deployed in warehouses, factory floors, and outdoor kiosks.
おすすめ
Embedded Industrial System
Industrial PCs, HMIs, and machine controllers add the LAN7800-I/VSX to gain a deterministic Gigabit Ethernet port when the host SoC provides only USB. Its SuperSpeed USB bus delivers wire-rate LAN throughput without taxing the host CPU with software networking stacks, critical for SCADA polling loops. The -40°C to +85°C industrial range supports outdoor cabinets and uncooled enclosures. IEEE 1588 timing support (where applicable) and hardware checksum offload improve real-time protocol determinism for Modbus TCP, EtherNet/IP, and PROFINET gateway designs.
おすすめ
Test and Measurement Instrument
Bench instruments, protocol analyzers, and data loggers use the LAN7800-I/VSX to add a USB-attached Gigabit Ethernet port for lab automation and remote control. Its hardware TCP/IP offload lets the instrument CPU focus on measurement acquisition rather than network stack processing. The 802.1Q VLAN tagging supports isolated lab networks, while the industrial temperature rating accommodates temperature-controlled but variable lab environments. The 48-SQFN package's compact footprint is ideal for portable handheld instruments where PCB real estate is at a premium.
おすすめ
おすすめ製品の概要
エンジニアリング参考データ: LAN7800-I/VSX — 比較、設計ガイダンス、コンプライアンス情報。
選定ガイド
代替品との比較
| パラメータ | この製品 | LAN7800/VSX |
|---|---|---|
| Brand | Microchip Technology | Microchip Technology |
| Package | 48-SQFN (VSX) 6x6 mm | 48-SQFN (VSX) 6x6 mm - same |
| Operating Temperature | -40C to +85C (Industrial) | 0C to +70C (Commercial) |
| USB Interface | USB 3.1 Gen 1 (5 Gbps) | USB 3.1 Gen 1 (5 Gbps) |
| Ethernet Speed | 10/100/1000 Mbps | 10/100/1000 Mbps |
| Integrated Gigabit PHY | Yes | Yes |
| Jumbo Frame Support | Up to 9 KB | Up to 9 KB |
| Energy Efficient Ethernet | IEEE 802.3az | IEEE 802.3az |
| Unit Price (qty 1) | $7.95 | Lower (commercial grade) |
主な差別化要因
- Industrial temperature grade with same silicon as commercial variant （vs LAN7800/VSX)
- Single-chip USB 3.1 + Gigabit MAC + Gigabit PHY integration （vs LAN7800/VSX)
- Bus-powered USB 3.0 operation （vs Generic USB 2.0 Ethernet bridges)
設計ノート
USB 3.0 SuperSpeed differential pairs (USB3_TXDP/N, USB3_RXDP/N) require 90-ohm differential impedance and matched length within 150 mils. Per Microchip's LAN7800 SQFN Schematic Checklist (Rev B), route SuperSpeed pairs over a continuous reference ground plane with no splits; avoid via stubs by using micro-vias on break-out from the BGA-style QFN pad array. Decoupling capacitors on VDD12A pins (25, 30, 44) must be placed within 100 mils of each pin.
Estimated: at USB 3.1 Gen 1 SuperSpeed active mode with Gigabit link at full throughput, the LAN7800-I/VSX dissipates approximately 0.6 W. With a typical SQFN-48 theta_JA near 35 C/W on a 4-layer 1 oz PCB, this yields approximately 21 C junction temperature rise above ambient - well within the 125 C maximum. The exposed thermal pad (pin 49) MUST be soldered to a continuous ground plane with at least 4 thermal vias (0.25 mm drill, 0.5 mm pitch) to the inner ground layer for reliable thermal dissipation.
Do not omit the ferrite bead between the internal +1.2V switching regulator output and VDD12A pins (25, 30, 44) per the LAN7800 schematic checklist - these pins power the analog Gigabit PHY and USB PLL/AFE blocks, and bypassing them through a single rail introduces switching noise into the PHY that will fail Ethernet compliance tests. Also, do not share the 25 MHz crystal ground with high-current digital ground return paths.
コンプライアンス情報
RoHS and REACH compliant per Microchip product page. AEC-Q100 not qualified - this is a commercial/industrial-grade bridge IC, not an automotive-qualified part. Halogen-free per Microchip material declaration.
