LAN91C111-NS - 10/100 Ethernet MAC+PHY | Microchip
MPN： LAN91C111-NS ✓ 啟用中LAN91C111-NS 概覽
An Ethernet MAC and PHY controller is an integrated network interface for embedded equipment. The MAC manages frame handling and the CSMA/CD protocol, while the PHY connects the digital controller to a 10/100 Base-T Ethernet physical layer. Combining both functions reduces system complexity, conserves board area, and allows an embedded processor to communicate through a parallel host bus rather than requiring a separate Ethernet PHY.
The LAN91C111-NS supports dual-speed operation at 100 Mbps or 10 Mbps with AutoNegotiation, as described in the manufacturer application note. Its architecture includes 8 KB of dynamically configurable transmit and receive FIFO SRAM, helping decouple host-bus traffic from network-frame activity. The parallel interface can operate at 32, 16, or 8 bits, providing flexibility for embedded processors with different external-bus capabilities.
For 100BASE-TX operation, the descrambler processes the scrambled data recovered from the medium, follows the IEEE 802.3 scrambling rules, aligns the data on correct 5B word boundaries, and passes it to the 4B5B decoder. This mixed-signal architecture supports both 10BASE-T and 100BASE-TX networking while maintaining a host-facing digital interface. The manufacturer identifies the device as suitable for third-generation embedded Fast Ethernet connectivity solutions.
Typical uses include industrial automation controllers, embedded network gateways, factory data-acquisition equipment, building-control systems, print servers, and compact network-access appliances. The selectable host-bus width is especially useful when balancing throughput, PCB routing, and processor-bus compatibility. AutoNegotiation allows the controller to operate with 10 Mb/s or 100 Mb/s network links while reducing manual speed configuration.
Design the power, ground, clock, magnetics, and network-line interface according to the manufacturer reference implementation. Preserve the recommended placement and decoupling of the Ethernet magnetic components and provide the specified oscillator and crystal arrangement to avoid timing or compliance problems. Validate the completed board for conducted emissions, immunity, and Ethernet link performance before production.
This page organizes the controller's principal network functions, interface options, package characteristics, application guidance, and qualified same-footprint alternatives. It also highlights design considerations that help engineers distinguish protocol coverage, host-bus flexibility, FIFO behavior, and physical-layer implementation without treating the device as a generic Ethernet block.
直接替換替代品，適用於 LAN91C111-NS — 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： LAN91C111-NS （相同外形與佔位） — 差異在於 Device Type, Package.
LAN91C111I-NU
✅ 直接替換📋 參考替代品（不在目錄中）
LAN91C111I-NS
✅ 直接替換📋 參考替代品（不在目錄中）
LAN91C111-NU
✅ 直接替換聯絡詢價
查看資料表 →LAN91C111-NS-E2
✅ 直接替換📋 參考替代品（不在目錄中）
LAN91C111
✅ 直接替換📋 參考替代品（不在目錄中）
LAN91C111-NS 規格
| Ethernet Data Rate | 10 Mb/s or 100 Mb/s |
| Integrated Functions | 10/100 Ethernet MAC and PHY |
| Protocol Support | CSMA/CD |
| Host Interface Width | 32-bit, 16-bit, or 8-bit parallel |
| Physical Network Standard | 10/100 Base-T/TX |
| Internal FIFO SRAM | 8 KB dynamically configurable TX/RX |
| AutoNegotiation | Supported |
| Device Type | Mixed-signal analog/digital Ethernet controller |
| 封裝 | 128-QFP (14 mm x 20 mm) |
| 腳位數 | 128 pins |
| 安裝類型 | Surface mount |
| 100BASE-TX Descrambling | IEEE 802.3 compliant |
| Line Encoding | 4B5B decoding and 5B word-boundary alignment |
| RoHS Compliance | unknown |
| REACH Compliance | unknown |
| AEC-Q100 Qualification | not_applicable |
LAN91C111-NS 128-qfp (14 mm x 20 mm) 腳位配置指南
LAN91C111-NS（128-qfp (14 mm x 20 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： LAN91C111-NS.
請參閱 資料表 以查看完整腳位配置。
典型應用
LAN91C111-NS 適用於 6 應用s: Industrial Automation Controller, Embedded Network Gateway, Factory Data-Acquisition System, Building-Control and HVAC Node, Networked Print and Copy Appliance, Embedded Test and Measurement Instrument.
Industrial Automation Controller
The LAN91C111-NS suits embedded PLCs, machine controllers, and industrial gateways that require deterministic Ethernet connectivity without a separate MAC and PHY. Its 10/100 Mb/s dual-speed support and AutoNegotiation allow operation across 10BASE-T and 100BASE-TX networks, while the configurable 8 KB TX/RX FIFO buffers host traffic from the processor. The selectable 32-, 16-, or 8-bit parallel interface helps match the controller to different embedded bus architectures and reduce unnecessary wiring. Use the manufacturer reference network circuit for magnetic-component selection, termination, routing, and isolation so the implemented link complies with the intended Ethernet environment.
推薦
Embedded Network Gateway
LAN91C111-NS provides an integrated network interface for gateways that collect local data and forward it over 10/100 Ethernet. The MAC and PHY functions are combined in one mixed-signal device, reducing the number of components compared with separate implementations. Its 8 KB dynamically configurable FIFO SRAM provides frame buffering between network activity and the embedded host bus. The 8-bit, 16-bit, or 32-bit host width permits a deliberate tradeoff between processor-bus simplicity, wiring density, and transfer performance. Designers should follow the manufacturer reference layout for the Ethernet magnetics, clocking network, power distribution, and high-speed signal routing.
推薦
Factory Data-Acquisition System
The LAN91C111-NS can connect sensors, counters, and process-monitoring equipment to an Ethernet network at 10 or 100 Mb/s. Its parallel host interface lets the acquisition processor transfer frame data through 8-, 16-, or 32-bit access, while the integrated 8 KB TX/RX FIFO separates network traffic from some host-bus activity. AutoNegotiation supports mixed-speed factory networks without fixed link configuration. Because the controller combines digital MAC logic and analog PHY functions, designers should maintain the recommended grounding and decoupling strategy and place the Ethernet magnetic components according to the manufacturer reference implementation.
推薦
Building-Control and HVAC Node
LAN91C111-NS is applicable to compact building-management controllers, HVAC control panels, and environmental-monitoring nodes that need Fast Ethernet connectivity. The controller supports both 10 Mb/s and 100 Mb/s operation, allowing common hardware to serve legacy and higher-speed building networks. Its selectable parallel bus width supports integration with microcontrollers and application processors of different bus capabilities, while the configurable TX/RX FIFO helps isolate network-frame handling from host transactions. Confirm the required device temperature grade and use the manufacturer application reference to implement clocking, Ethernet filtering, magnetics, and physical-layer isolation correctly.
推薦
Networked Print and Copy Appliance
The LAN91C111-NS can provide Ethernet access in embedded print servers, scanners, copy-control modules, and other appliance controller boards. A single-chip MAC and PHY reduces the physical network-interface footprint, while the 32-, 16-, or 8-bit host interface permits a direct connection to processors with different external-bus widths. At 100 Mb/s, the PHY includes the IEEE 802.3 descrambling, 5B word-boundary alignment, and 4B5B decoding functions described in the manufacturer datasheet. Layout planning should preserve the recommended magnetic-component spacing, return paths, and supply decoupling to reduce emissions and maintain robust link behavior.
推薦
Embedded Test and Measurement Instrument
LAN91C111-NS can add networked configuration, status reporting, and remote data access to embedded test and measurement equipment. Supporting both 10 Mb/s and 100 Mb/s with AutoNegotiation improves compatibility with laboratory networks operating at different speeds. The parallel host interface offers a path to connect the controller to a supervisory processor, while the 8 KB dynamically configurable FIFO SRAM supports queued frame movement. For accurate operation, use the manufacturer's prescribed clock source, decoupling network, Ethernet magnetic components, and reference-layout geometry. Confirm EMC and Ethernet compliance on the finished assembly because sensitive measurement hardware can be affected by switching and Ethernet-interface noise.
推薦
推薦產品摘要
工程參考資料，適用於 LAN91C111-NS — 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 | LAN91C111I-NU | LAN91C111I-NS | LAN91C111-NU | LAN91C111-NS-E2 | LAN91C111 |
|---|---|---|---|---|---|---|
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Package | 128-QFP (14 mm x 20 mm) | 128-QFP (14 mm x 20 mm) | 128-QFP (14 mm x 20 mm) | 128-QFP (14 mm x 20 mm) | 128-QFP (14 mm x 20 mm) | 128-QFP (14 mm x 20 mm) |
| Ethernet Speed | 10 Mb/s or 100 Mb/s | 10 Mb/s or 100 Mb/s | 10 Mb/s or 100 Mb/s | 10 Mb/s or 100 Mb/s | 10 Mb/s or 100 Mb/s | 10 Mb/s or 100 Mb/s |
| Integrated Functions | 10/100 Ethernet MAC and PHY | 10/100 Ethernet MAC and PHY | 10/100 Ethernet MAC and PHY | 10/100 Ethernet MAC and PHY | 10/100 Ethernet MAC and PHY | 10/100 Ethernet MAC and PHY |
| Host Interface Width | 32-bit, 16-bit, or 8-bit parallel | 32-bit, 16-bit, or 8-bit parallel | 32-bit, 16-bit, or 8-bit parallel | 32-bit, 16-bit, or 8-bit parallel | 32-bit, 16-bit, or 8-bit parallel | 32-bit, 16-bit, or 8-bit parallel |
| Internal FIFO SRAM | 8 KB dynamically configurable TX/RX | 8 KB dynamically configurable TX/RX | 8 KB dynamically configurable TX/RX | 8 KB dynamically configurable TX/RX | 8 KB dynamically configurable TX/RX | 8 KB dynamically configurable TX/RX |
| AutoNegotiation | Supported | Supported | Supported | Supported | Supported | Supported |
| Protocol | CSMA/CD | CSMA/CD | CSMA/CD | CSMA/CD | CSMA/CD | CSMA/CD |
| Primary Parameter Difference | Reference device | 0% measurable difference in primary technical parameters | 0 Mb/s speed and 0 KB FIFO-capacity difference | 0 Mb/s speed and 0 KB FIFO-capacity difference | 0 Mb/s speed and 0 KB FIFO-capacity difference | 0 Mb/s speed and 0 KB FIFO-capacity difference |
| Ordering Designation | LAN91C111-NS | I-NU ordering designation | I-NS ordering designation | NU ordering designation | NS-E2 ordering designation | Base ordering designation |
主要差異化特點
- Integrated 10/100 Ethernet MAC and PHY (對比LAN91C111I-NU)
- Selectable parallel host-interface width (對比LAN91C111I-NS)
- Configurable frame buffering for embedded hosts (對比LAN91C111-NU)
- Automatic dual-speed link operation (對比LAN91C111-NS-E2)
設計說明
Implement the Ethernet physical interface according to the manufacturer reference layout. Place the network magnetic components at the board edge in the orientation shown by the reference design, maintain the recommended clearance around transformer pins, and route differential pairs as short and continuous as practical. Decoupling and ground-return planning must preserve the mixed-signal performance of the integrated PHY while minimizing radiated emissions and susceptibility to adjacent digital circuitry.
Use the manufacturer-specified clock source and consider all clock, reset, and host-bus timing requirements when assigning processor interfaces. The controller supports 32-bit, 16-bit, and 8-bit host access, but the operating mode must agree with the wiring, register configuration, and timing design. Keep high-speed host signals away from the Ethernet transformer area and provide continuous ground references beneath signal routes where the recommended layout requires them.
Do not select a replacement from the family name alone. Although the listed variants share the 128-QFP format and principal 10/100 Mb/s MAC-and-PHY functions, ordering suffixes can denote temperature grade, qualification, sourcing status, or legacy conditions. Compare the complete manufacturer datasheet limits, environmental requirements, and product-lifecycle status before replacing LAN91C111-NS in an existing PCB or approved BOM.
合規資訊
The manufacturer datasheet and product information do not state the requested compliance details. IEEE 802.3 appears in the manufacturer datasheet as a networking requirement rather than a product-compliance declaration.
