LAN9303-ABZJ - 3-Port 10/100 Ethernet Switch | Microchip
MPN： LAN9303-ABZJ ✓ 啟用中LAN9303-ABZJ 概覽
An Ethernet switch is a network-semiconductor device that receives frames at one port, examines their destination information, and forwards traffic to the appropriate port or ports. A managed switch adds configuration and monitoring functions that are useful when a product needs controlled network behavior, diagnostics, or host access. Within the broader hierarchy, the LAN9303 is a managed Ethernet switch, an Ethernet interface IC, and ultimately a semiconductor designed for embedded networking.
The principal feature set includes three integrated 10/100 Ethernet ports, management support, a compact surface-mount footprint, and host-controlled configuration through the supported device interfaces. Its 8 mm by 8 mm QFN construction helps reduce board area compared with discrete three-port networking solutions. This makes the device suitable for adding multiple Ethernet connections to embedded systems without requiring a separate full-size switch module.
The LAN9303 architecture integrates the switching function and 10/100 Ethernet physical-layer functions into one device. Integration can reduce external component count, simplify board routing, and reduce software effort because one local device can manage multiple copper Ethernet ports. This integration is especially valuable in consumer electronics, industrial controllers, embedded appliances, and compact network-interface equipment where physical space and development schedules constrain the design.
Typical implementations include industrial automation controllers, embedded network appliances, consumer electronics with multiple Ethernet ports, and equipment that bridges or distributes 10/100 traffic. The three-port configuration supports designs where a host connects to one port while external devices use the remaining ports, or where several machine-control nodes share a compact Ethernet backbone.
A key design consideration is that this is a 10/100-class Ethernet switch rather than a Gigabit Ethernet device. Designs requiring 1000Base-T operation must use a different Ethernet switch. Board layout should follow the manufacturer's reference schematic and layout guidance, including controlled-impedance differential pairs, proper magnetics interface connections, solid supply and ground planes, and decoupling close to the device.
This product page consolidates the device identity, package information, verified sourcing links, functional alternatives, application guidance, and engineering-oriented comparison points. It also identifies where detailed electrical characteristics or absolute maximum ratings must be confirmed in the manufacturer datasheet before a new design is released.
直接替換替代品，適用於 LAN9303-ABZJ — 相同封裝，腳位對腳位相容。需重新設計 PCB 的不同封裝零件不列入。
LAN9303I-ABZJ
✅ 直接替換📋 參考替代品（不在目錄中）
LAN9303-ABZJ-TR
✅ 直接替換📋 參考替代品（不在目錄中）
LAN9303I-ABZJ-TR
✅ 直接替換📋 參考替代品（不在目錄中）
LAN9303-ABZJ 最大額定值與電氣特性
| Product Type | Managed Ethernet switch |
| Number of Ethernet Ports | 3 ports |
| Ethernet Speed | 10/100 Base-T/TX |
| 封裝 | 56-pin QFN, 8 mm x 8 mm |
| 安裝類型 | Surface mount |
| Management Support | Managed switch |
| PHY Count | 3 integrated 10/100 PHYs |
| Maximum Data Rate | 100 Mbit/s per port |
| RoHS 狀態 | EU RoHS compliant |
| REACH Status | REACH compliant |
LAN9303-ABZJ 56-pin qfn, 8 mm x 8 mm 腳位配置指南
LAN9303-ABZJ（56-pin qfn, 8 mm x 8 mm 封裝）的腳位配置。 腳位編號、功能與連接圖定義於製造商資料手冊中。請參閱該手冊以取得確切的封裝尺寸與焊接指引。
無詳細腳位定義資料： LAN9303-ABZJ.
請參閱 資料表 以查看完整腳位配置。
典型應用
LAN9303-ABZJ 適用於 6 應用s: Industrial Automation Controller, Embedded Network Appliance, Consumer Electronics with Ethernet, Industrial IoT Gateway, Test and Measurement Front Panel, Building and Automation Controller.
Industrial Automation Controller
The LAN9303-ABZJ fits industrial controllers that need three compact 10/100 Ethernet connections instead of a larger external switch module. Its three-port managed-switch architecture allows a control processor to communicate through one port while machines, sensors, or service equipment occupy the other two. The integrated 8 mm by 8 mm QFN implementation reduces PCB area, while local switching reduces unnecessary traffic on the host processor. Use the manufacturer reference schematic to reproduce the magnetics, differential routing, supply decoupling, and management-interface connections. The exact ordering code's temperature range and industrial qualification should be checked before deployment in temperature-extreme or safety-related equipment.
推薦
Embedded Network Appliance
The LAN9303-ABZJ is useful in compact appliances that expose multiple wired Ethernet connections to a host processor. A common arrangement uses one port for the host or upstream network and two ports for service equipment, cameras, or access peripherals. Because the LAN9303 combines three managed 10/100 ports in one 56-pin QFN package, the design can avoid a separate three-port switch and its additional board area. Management features also allow firmware to monitor or configure network behavior rather than treating every port as an independent interface. Final Ethernet magnetics, isolation, connector choices, and board partitions should follow the manufacturer reference design.
推薦
Consumer Electronics with Ethernet
The LAN9303-ABZJ supports consumer products that need multiple 10/100 Ethernet ports but have limited enclosure and PCB space. The managed three-port switch can provide direct connectivity among a product's service interface, local computer, printer, game accessory, or network bridge while keeping frame forwarding local. Its compact 8 mm by 8 mm QFN package is preferable to implementing three separate PHY channels and a discrete switch. Product firmware should use the documented host and management interfaces for initialization, address filtering, link monitoring, and controlled startup. Verify the exact temperature range, magnetics interface, and compliance obligations for the finished consumer product.
推薦
Industrial IoT Gateway
The LAN9303-ABZJ is well matched to an IoT gateway requiring three 10/100 ports for a management network and two field-device networks. Local switching provides an efficient path between attached devices without routing every frame through the gateway's main processor. The managed-switch function is useful for link monitoring, port configuration, and diagnostics, while the small QFN footprint preserves board area for radio, storage, or sensor interfaces. Implement differential Ethernet routing as controlled-impedance pairs, isolate each external copper port according to the product's safety requirements, and use the manufacturer's reference layout for the device, magnetics, and exposed-pad connection.
推薦
Test and Measurement Front Panel
The LAN9303-ABZJ can consolidate three 10/100 Ethernet connections in an instrument front panel, remote laboratory interface, or production-test fixture. One port may connect to a test controller, one to an instrument, and one to an external service network. Integrated switching reduces the number of external Ethernet components while managed operation supports port diagnostics and controlled configuration. The device should be paired with the exact external magnetics and connector arrangement recommended by the manufacturer, because Ethernet isolation and return-path requirements affect board partitioning. Confirm whether 100 Mbit/s operation is sufficient for captured test data and whether the target temperature range covers the instrument environment.
推薦
Building and Automation Controller
The LAN9303-ABZJ supports building controllers, access-control panels, and room-control equipment that need to combine several wired Ethernet nodes with a main controller. The three managed 10/100 ports can link the controller, an uplink, and a local access device while conserving space in a wall-mounted enclosure. Because building equipment may operate in varied ambient conditions, engineers should compare the target ordering code's temperature limits with LAN9303I-ABZJ. Maintain separation between Ethernet and low-voltage signal domains where required, use qualified external magnetics, and implement the manufacturer's recommended power and ground layout to preserve network performance.
推薦
推薦產品摘要
工程參考資料，適用於 LAN9303-ABZJ — 比較、設計指引及合規資訊。
選型指南
與替代品比較
| 參數 | 本產品 | LAN9303I-ABZJ | LAN9303-ABZJ-TR | LAN9303I-ABZJ-TR |
|---|---|---|---|---|
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Package | 56-QFN (8x8) | 56-QFN (8x8) | 56-QFN (8x8) | 56-QFN (8x8) |
| Ethernet Port Count | 3 ports | 3 ports | 3 ports | 3 ports |
| Ethernet Speed | 10/100 Base-T/TX | 10/100 Base-T/TX | 10/100 Base-T/TX | 10/100 Base-T/TX |
| Switch Type | Managed Ethernet switch | Managed Ethernet switch | Managed Ethernet switch | Managed Ethernet switch |
| Temperature Designation | LAN9303 | LAN9303I industrial designation | LAN9303 designation | LAN9303I industrial designation |
主要差異化特點
- Three integrated 10/100 ports in one 56-pin QFN device (對比LAN9303I-ABZJ)
- Exact electrical ordering code with unchanged core specifications (對比LAN9303-ABZJ-TR)
- Compact 8 mm by 8 mm managed Ethernet integration (對比LAN9303I-ABZJ-TR)
設計說明
Route each 10/100 Ethernet differential pair as a controlled-impedance, continuously referenced connection, following the manufacturer reference layout and the Ethernet magnetics vendor's guidance. Keep the switch, magnetics, and connector interface in a defined high-speed region, minimize stubs, and avoid placing unrelated slow or noisy circuitry beneath the Ethernet differential pairs. Confirm connector and magnetics placement before finalizing the board outline.
Place all decoupling capacitors close to their associated supply and ground pins, and connect the QFN exposed pad to the ground plane using the land pattern and via arrangement specified by Microchip. Avoid creating long current loops between the device, capacitor, and plane. Review the datasheet's voltage, current, sequencing, and power-up requirements before selecting the system supply and any external Ethernet magnetics.
Do not treat a three-port 10/100 switch as a Gigabit Ethernet substitute, and do not assume that matching the package dimensions proves complete interchangeability. Before approving LAN9303I-ABZJ or a -TR configuration, verify pin functions, temperature limits, reset and clock requirements, management interfaces, exposed-pad construction, and the required Ethernet magnetics against the manufacturer documentation.
Preserve the intended 10/100BASE-T link budget by following the supported magnetics selection, connector layout, and isolation guidance in the application circuit. Keep chassis and board-ground connections consistent with the product's isolation strategy, and test compliance at the finished-product interface rather than only at the switch pins. Ethernet performance can be affected by connector construction, cable faults, return paths, and the external magnetics as much as by the IC.
合規資訊
EU RoHS and REACH compliance are stated in the Abacus Technologies product listing. Lead-free, halogen-free, conflict-minerals, and AEC-Q100 status are not stated for the exact ordering code.
