LAN7800-I/VSX - USB 3.1 Gen 1 to Gigabit Ethernet Bridge | Microchip
Référence : LAN7800-I/VSX ✓ Actif| Qté | Prix unitaire | Total |
|---|---|---|
| 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 Présentation
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.
Alternatives de remplacement direct pour LAN7800-I/VSX — même boîtier, compatible broche à broche. Les références à boîtier différent nécessitant une retouche du PCB sont exclues.
Variantes de cette série
Modèles de la même série directement compatibles avec LAN7800-I/VSX (même facteur de forme et même empreinte) — différant par Package, Supply Voltage, Energy Efficient Ethernet, Ethernet Speed, Operating Temperature.
Outil de comparaison rapide — sélectionnez des références alternatives pour une comparaison côte à côte :
LAN7800/VSX
✅ Remplacement direct✓ En stock
Contactez-nous pour le prix
Voir la fiche technique →LAN7800T/VSX
✅ Remplacement direct ⚠️ Spécifications non vérifiées✓ En stock
$8.1 / unité
Voir la fiche technique →LAN7800-I/VSX Spécifications
| 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) |
| Boîtier | 48-SQFN (VSX) 6x6 mm |
| Température de fonctionnement | -40°C to +85°C (Industrial) |
| Tension d'alimentation | 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) |
| Statut RoHS | Compliant |
Configuration des broches de LAN7800-I/VSX
| Broche 1 | VDD33A — +3.3V analog supply |
| Broche 2 | VDD12A_PLL — +1.2V analog supply (PLL) |
| Broche 3 | VDD12A_AFE — +1.2V analog supply (AFE) |
| Broche 4 | VDD33A_USB — +3.3V analog supply (USB PHY) |
| Broche 5 | VBUS — USB VBUS detect (5V) |
| Broche 6 | USB_DP — USB D+ data line |
| Broche 7 | USB_DN — USB D- data line |
| Broche 8 | USB3_TXDP — USB 3.0 SuperSpeed TX+ (differential) |
| Broche 9 | USB3_TXDN — USB 3.0 SuperSpeed TX- (differential) |
| Broche 10 | USB3_RXDP — USB 3.0 SuperSpeed RX+ (differential) |
| Broche 11 | USB3_RXDN — USB 3.0 SuperSpeed RX- (differential) |
| Broche 12 | RESET_N — Active-low hardware reset |
| Broche 13 | GPIO0 — General purpose I/O 0 |
| Broche 14 | GPIO1 — General purpose I/O 1 |
| Broche 15 | GPIO2 — General purpose I/O 2 |
| Broche 16 | GPIO3 — General purpose I/O 3 |
| Broche 17 | GPIO4 — General purpose I/O 4 |
| Broche 18 | GPIO5 — General purpose I/O 5 |
| Broche 19 | GPIO6 — General purpose I/O 6 |
| Broche 20 | GPIO7 — General purpose I/O 7 |
| Broche 21 | VDD18_DIG — +1.8V digital supply |
| Broche 22 | VDD18A — +1.8V analog supply |
| Broche 23 | VDD33_DIG — +3.3V digital supply |
| Broche 24 | VDD12_CORE — +1.2V digital core supply (internal LDO out) |
| Broche 25 | VDD12A — +1.2V analog supply (Gigabit PHY) |
| Broche 26 | GND — Ground |
| Broche 27 | ETH_MDIAP — Ethernet MDI pair A+ |
| Broche 28 | ETH_MDIAN — Ethernet MDI pair A- |
| Broche 29 | ETH_MDIBP — Ethernet MDI pair B+ |
| Broche 30 | VDD12A — +1.2V analog supply (PHY) |
| Broche 31 | ETH_MDIBN — Ethernet MDI pair B- |
| Broche 32 | ETH_MDICP — Ethernet MDI pair C+ |
| Broche 33 | ETH_MDICN — Ethernet MDI pair C- |
| Broche 34 | ETH_MDIDP — Ethernet MDI pair D+ |
| Broche 35 | ETH_MDIDN — Ethernet MDI pair D- |
| Broche 36 | ETH_LED0 — Ethernet LED 0 (link/activity) |
| Broche 37 | ETH_LED1 — Ethernet LED 1 (speed) |
| Broche 38 | ETH_LED2 — Ethernet LED 2 (link status) |
| Broche 39 | XTAL_IN — 25 MHz crystal input |
| Broche 40 | XTAL_OUT — 25 MHz crystal output |
| Broche 41 | VDD33A_ETH — +3.3V analog supply (Ethernet PHY) |
| Broche 42 | VDD12A_ETH — +1.2V analog supply (Ethernet PHY core) |
| Broche 43 | VDD12A_PLL2 — +1.2V analog supply (Ethernet PLL) |
| Broche 44 | VDD12A — +1.2V analog supply (shared) |
| Broche 45 | NC — Not connected (per datasheet) |
| Broche 46 | NC — Not connected (per datasheet) |
| Broche 47 | NC — Not connected (per datasheet) |
| Broche 48 | NC — Not connected (per datasheet) |
| Broche 49 | EP — Exposed thermal pad - must be soldered to ground plane |
Applications typiques
LAN7800-I/VSX convient pour 6 applications: 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.
Recommandé
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.
Recommandé
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.
Recommandé
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.
Recommandé
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.
Recommandé
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.
Recommandé
Récapitulatif des produits recommandés
Données de référence d'ingénierie pour LAN7800-I/VSX — comparaison, recommandations de conception et informations de conformité.
Guide de sélection
Comparaison avec les alternatives
| Paramètre | Ce produit | 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) |
Principaux différenciateurs
- 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)
Notes de conception
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.
Informations de conformité
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.
