KSZ8031RNL - 10/100 Ethernet PHY | Microchip Technology
MPN： KSZ8031RNL ✓ 啟用中KSZ8031RNL 概覽
An Ethernet physical layer transceiver is the circuit that converts digital frame data from an Ethernet media access controller into signals suitable for twisted-pair cabling, then converts received cable signals back into digital data. This PHY belongs to the hierarchy Ethernet transceiver > physical layer device > network interface IC > semiconductor. RMII provides a standardized parallel connection between the PHY and a compatible Ethernet processor or switch.
The KSZ8031RNL supports both 10Base-T and 100Base-TX operation, allowing one physical-layer design to serve legacy 10 Mb/s and Fast Ethernet 100 Mb/s links. Its full-duplex RMII interface supports simultaneous transmit and receive activity, while single-supply operation simplifies system power design. The 24-QFN package also supports space-constrained embedded networking designs.
Compared with the related KSZ8021RNL, the KSZ8031RNL uses the RMII reference-clock arrangement suited to systems requiring a 25 MHz reference. The RMII interface exposes the PHY connections required for data, control, carrier sense, and clock signaling between the transceiver and Ethernet MAC. The manufacturer documentation also identifies the device as a direct-interface physical layer rather than a complete Ethernet controller.
Typical uses include industrial Ethernet equipment, embedded control systems, IP cameras, network switches, serial-to-Ethernet products, and compact data-acquisition devices. The device is particularly appropriate when a host processor already includes an RMII-compatible Ethernet MAC and the PCB area is limited.
Design the PCB with the 24-QFN footprint, power and decoupling capacitors, a 50 MHz differential clock arrangement, and an RMII interface routed according to the manufacturer datasheet. Confirm PHY address, strap configuration, magnetics, termination, and cable-side layout before releasing the design.
This product page combines the manufacturer electrical description, package information, application guidance, replacement cross-checks, and PCB-focused design considerations to support faster component selection and implementation.
直接替換替代品，適用於 KSZ8031RNL — 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。
此系列的變體
與下列產品可直接替換的同系列型號： KSZ8031RNL （相同外形與佔位） — 差異在於 Package, Product Type, Cable Type, Ethernet Speed Support, Interface.
KSZ8021RNL
✅ 直接替換 ⚠️ 規格未經驗證聯絡詢價
查看資料表 →KSZ8031RNLI
✅ 直接替換📋 參考替代品（不在目錄中）
KSZ8081RNACA-TR
✅ 直接替換聯絡詢價
查看資料表 →KSZ8031RNL 規格
| Product Type | 10Base-T/100Base-TX Ethernet physical layer transceiver |
| Ethernet Speed Support | 10 Mb/s and 100 Mb/s |
| 供應電壓 | 3.3 V |
| 介面 | Reduced Media Independent Interface (RMII) |
| Duplex Mode | Full duplex |
| Cable Standard | CAT-5 unshielded twisted pair (UTP) |
| Port Count | 1 port |
| 封裝 | 24-QFN (4 x 4 mm) |
| 安裝類型 | Surface mount |
| RMII Reference Clock | 25 MHz |
| Media Interface | 10Base-T/100Base-TX |
| Data Link Standard | Ethernet |
| Evaluation Board | KSZ8031RNL-EVAL |
KSZ8031RNL 24-qfn (4 x 4 mm) 腳位配置指南
KSZ8031RNL（24-qfn (4 x 4 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： KSZ8031RNL.
請參閱 資料表 以查看完整腳位配置。
典型應用
KSZ8031RNL 適用於 6 應用s: Industrial Ethernet Control, Embedded Network Gateway, IP Camera Connectivity, Compact Network Switch, Data Acquisition Terminal, Networked Test Equipment.
Industrial Ethernet Control
The KSZ8031RNL suits industrial controllers that require a single 10/100 Ethernet port and already provide an RMII-compatible MAC. Its support for both 10Base-T and 100Base-TX allows the controller to negotiate common industrial network speeds without adding a separate physical-layer device. Full-duplex operation supports simultaneous control traffic and data transfer, while the 24-QFN footprint preserves board area in compact DIN-rail or embedded systems. The design must include suitable Ethernet magnetics, isolation components, 3.3 V decoupling, and a controlled 25 MHz RMII reference clock. Cable-side layout should follow the manufacturer application guidance to maintain differential signal integrity and reliable network attachment.
推薦
Embedded Network Gateway
The KSZ8031RNL adds wired Ethernet connectivity to an embedded gateway when the host processor already contains an RMII MAC. The device handles 10 Mb/s and 100 Mb/s operation over CAT-5 UTP, making it suitable for configuration ports, service interfaces, and local supervisory networks. Its 24-QFN package helps reduce connector-adjacent routing congestion in compact gateway boards. Designers should budget for an Ethernet transformer or integrated magnetics, magnetic-field spacing, chassis or board grounding strategy, and low-ESR supply decoupling. The RMII timing path also requires short, length-matched routing because the 25 MHz clock and associated data signals must meet the manufacturer interface requirements.
推薦
IP Camera Connectivity
The KSZ8031RNL can provide the wired 10/100 Ethernet physical layer for an IP camera whose base processor includes an RMII-compatible MAC. Supporting both 10Base-T and 100Base-TX is useful during installation on older network segments while allowing higher throughput where available. The full-duplex interface supports continuous image traffic, and the small 24-QFN package is suitable for space-constrained camera electronics. The PCB should keep the PHY, magnetics, RJ45 interface, and digital host interface in a controlled layout with a clean separation between analog and digital return currents. Verify thermal performance around the exposed pad and provide the specified local bypass capacitance near the supply pins.
推薦
Compact Network Switch
The KSZ8031RNL can implement a copper Ethernet port in a compact switch or interface module whose switching fabric or host controller offers an RMII-compatible endpoint. Its 24-QFN package supports dense port layouts, while full-duplex 10/100 operation supports legacy edge ports and control-plane traffic. The single-supply 3.3 V architecture simplifies rail planning where the surrounding switch logic already operates at compatible levels. Placement of the PHY close to its magnetics reduces differential trace length and helps separate the high-energy cable-side network from the RMII domain. Designers should consult the manufacturer datasheet for strap settings, LED behavior, clock requirements, power sequencing, and the recommended magnetics implementation.
推薦
Data Acquisition Terminal
The KSZ8031RNL is appropriate for data-acquisition equipment that needs to publish measurements over 10/100 Ethernet while using an RMII-capable embedded controller. Fast Ethernet mode provides sufficient bandwidth for typical control, logging, and telemetry traffic, while 10Base-T support improves interoperability with older laboratory and plant networks. The small 24-QFN package leaves board area for analog front ends and connectors. Critical implementation work includes isolating the cable-side magnetics from sensitive measurement circuitry, controlling ground returns, and providing stable 3.3 V power with local high-frequency bypass. Validation should cover link negotiation, RMII timing, packet-loss behavior, and operation with the intended CAT-5 cable installation.
推薦
Networked Test Equipment
The KSZ8031RNL can add a 10/100 Ethernet service port to test and measurement equipment whose controller includes an RMII interface. The device supports both common Ethernet rates, enabling remote control, status reporting, and firmware delivery over existing copper networks. Its full-duplex operation suits continuous data transfer, and the compact 24-QFN package fits front-panel or internal communication boards. Use short RMII routing and controlled impedance or matched-length treatment where required by the interface specification, while placing magnetics and protection components near the connector. Chassis grounding and surge or ESD protection must be coordinated so that user-accessible cable interfaces do not introduce excessive coupling into the measurement circuitry.
推薦
推薦產品摘要
工程參考資料，適用於 KSZ8031RNL — 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 | KSZ8021RNL | KSZ8031RNLI | KSZ8081RNACA |
|---|---|---|---|---|
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Package | 24-QFN (4 x 4 mm) | 24-QFN (4 x 4 mm) | 24-QFN (4 x 4 mm) | 24-VFQFN |
主要差異化特點
- Matches the 25 MHz RMII reference arrangement (對比KSZ8021RNL)
- Uses the same compact 24-QFN footprint (對比KSZ8031RNLI)
- Documented as a complete replacement (對比KSZ8081RNACA)
設計說明
Place the KSZ8031RNL close to the Ethernet transformer and connector, while keeping the RMII side toward the host processor. Route the cable-side differential pairs as short, continuous pairs with symmetric geometry and a continuous reference plane. Maintain the manufacturer-specified separation from the exposed pad, supply components, and clock circuitry to reduce radiated emissions and susceptibility to cable-borne interference.
Implement the single 3.3 V supply on the PCB with local high-frequency bypass at the PHY supply pins and adequate bulk capacitance near the power entry point. Keep switching-regulator and inductor placement away from the Ethernet magnetics and cable-side traces. Confirm power-on sequencing and the allowable ramp condition in the manufacturer datasheet, particularly when the host processor and PHY share a reset-controlled supply.
Route the 25 MHz RMII reference clock and associated data signals on a continuous ground plane, with short point-to-point connections and no stubs. Check source-synchronous timing, clock skew, trace length, and load assumptions against the manufacturer interface specifications. Avoid placing test pads or unnecessary vias in clock-sensitive paths, and keep unrelated switching nodes away from the RMII region.
Do not substitute KSZ8021RNL without checking its 50 MHz RMII reference-clock requirement against the KSZ8031RNL's 25 MHz arrangement. Likewise, verify every configuration strap, LED connection, PHY address, and exposed-pad connection when using KSZ8031RNLI or KSZ8081RNACA. Package similarity alone does not confirm timing, thermal, or configuration compatibility.
合規資訊
The interface circuit is not an automotive-qualified device; RoHS, REACH, lead-free, halogen-free, and conflict-minerals status require confirmation from the manufacturer product declaration or product page.
