LAN9115-MT - 10/100 Ethernet Controller, 3.3V | Microchip
MPN: LAN9115-MT ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $3.98 | $3.98 |
| 10 | $0 | $0.00 |
| 100 | $0 | $0.00 |
| 500 | $0 | $0.00 |
| 1,000 | $0 | $0.00 |
LAN9115-MT Overview
An Ethernet controller is an interface IC that connects an embedded processor or programmable logic device to a physical Ethernet network. The controller manages higher-level station functions, while the integrated PHY handles the physical signaling required for 10BASE-T and 100BASE-TX links. Within the semiconductor hierarchy, this device is a network interface controller, a communications interface IC, and a system-level Ethernet connectivity component.
Verified product information identifies the LAN9115 as a full-featured single-chip 10/100 Ethernet controller intended for 16-bit embedded applications. Its parallel interface supports integration with processors that use a memory-mapped bus rather than a dedicated PCI interface. The supplied distributor classification also identifies a Base-T/TX PHY, while the product description emphasizes price-performance balance for medium-performance requirements.
The LAN9115 combines MAC-oriented controller functionality and physical-layer connectivity in one package. This consolidation can simplify PCB routing and reduce the number of external interface components, but the Ethernet magnetics, connector, termination, clock source, decoupling network, and firmware support remain essential parts of a working network subsystem. Its 3.3 V operation also places it in the supply domain of many embedded processors, FPGAs, and industrial controllers.
Typical uses include industrial control equipment, embedded gateways, factory data acquisition, instrumentation, building automation, serial-to-Ethernet products, and compact embedded servers. The LAN9115 is most appropriate where 10/100 Ethernet is sufficient and a 16-bit host interface is preferable to a PCI-based architecture. It can also form the network foundation for supervisory systems that exchange configuration, status, and diagnostic data.
Board design should reserve careful attention to the 25 MHz clock requirement, 3.3 V power distribution, PHY-to-magnetics routing, and manufacturer-recommended decoupling and layout practices. Because the verified snippets do not provide a complete timing, register, electrical-limit, or absolute-maximum specification set, designers should consult the official manufacturer datasheet before finalizing clock tolerances, impedance, magnetics selection, or software configuration.
This page consolidates verified product identity, package, interface, supply, and sourcing information into a practical selection record. It also distinguishes verified facts from unavailable details rather than guessing, while directing engineers to the official datasheet and authorized distributor listings for design validation and current commercial availability.
Drop-in alternatives for LAN9115-MT — same package, pin-to-pin compatible. Different-package parts requiring PCB rework are excluded.
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Request AlternativesLAN9115-MT Specifications
| Product Type | 10/100 Ethernet controller |
| Ethernet Support | 10BASE-T and 100BASE-TX |
| Integrated PHY | 10/100 Base-T/TX PHY |
| Host Interface | 16-bit parallel |
| Bus Architecture | Non-PCI |
| Nominal Supply Voltage | 3.3 V |
| Maximum Stated Clock Frequency | 25 MHz |
| Commercial Temperature Range | 0°C to 70°C |
| Package | 100-pin TQFP, 14 x 20 mm |
| Mounting Type | Surface mount |
| Core Function | Ethernet MAC and PHY integration |
| Target Performance Class | Medium-performance embedded networking |
| Primary Performance Objective | Price-performance ratio for 16-bit applications |
LAN9115-MT 100-pin tqfp, 14 x 20 mm Pin Configuration Guide
Pin configuration for LAN9115-MT (100-pin tqfp, 14 x 20 mm package). Pin numbering, functions, and connection diagrams are defined in the manufacturer datasheet. Refer to it for the exact footprint and soldering guidelines.
No detailed pinout data available for LAN9115-MT.
Refer to the datasheet for full pin configuration.
Typical Applications
LAN9115-MT is suitable for 6 applications: Industrial Ethernet Control, Factory Data Acquisition, Building Automation Gateway, Embedded Test Instrument, Serial-to-Ethernet Product, Compact Embedded Network Controller.
Industrial Ethernet Control
LAN9115-MT fits embedded controllers that exchange commands, status, and diagnostics over 10/100 Ethernet. Its 16-bit parallel host interface is suited to processors designed around a memory-mapped bus, while the integrated 10/100 Base-T/TX PHY reduces the external network-interface component count. The device's stated 0°C to 70°C range covers many indoor factory and building-control environments. Designers should budget clock, decoupling, magnetics, and connector requirements from the manufacturer reference design rather than treating the controller as a complete Ethernet jack implementation.
Recommended
Factory Data Acquisition
LAN9115-MT can connect a sensor controller or embedded edge device to an Ethernet-based acquisition system. Its 10BASE-T and 100BASE-TX support covers networks where medium performance is more important than gigabit throughput, and its 3.3 V nominal operation can simplify power architecture around compatible embedded logic. The 25 MHz maximum stated clock provides a concrete timing boundary for the design, but acquisition timing still depends on the host processor and interrupt path. Validate DMA, ISR latency, buffering, and protocol behavior in firmware.
Recommended
Building Automation Gateway
LAN9115-MT is appropriate for gateways that bridge sensors, controllers, or service equipment to an IP network. The 16-bit non-PCI interface aligns with many medium-performance embedded processors, while integration of the controller and Base-T/TX PHY can simplify the network section of the PCB. Its commercial 0°C to 70°C range may serve indoor HVAC, access, lighting, and facilities equipment. Firmware must implement the intended Ethernet stack and carefully handle link status, cable faults, traffic buffering, and network-security requirements.
Recommended
Embedded Test Instrument
LAN9115-MT can provide networked control and data access for instruments whose internal processor uses a 16-bit host bus. At 10/100 Ethernet speeds, the controller is suited to configuration transfers, status packets, firmware updates, and moderate measurement-data streams rather than sustained multi-gigabit transfer. The 3.3 V nominal supply and up-to-25-MHz clock specification support integration with conventional embedded logic. Designers should assess interrupt latency, host-bus contention, packet buffering, transformer selection, and grounded enclosure requirements for reliable laboratory use.
Recommended
Serial-to-Ethernet Product
LAN9115-MT fits legacy serial equipment that needs a network port without adopting a PCI host architecture. An embedded processor can receive commands through UART or another local interface, package them for Ethernet, and manage link state and diagnostics. The 10/100 capability is more than adequate for many configuration channels and modest telemetry rates, while the integrated PHY reduces board area. Firmware should define reconnect behavior, authentication, watchdog recovery, and buffering because those system requirements are not established by the LAN9115 hardware specifications.
Recommended
Compact Embedded Network Controller
LAN9115-MT is useful when a compact control appliance needs a conventional parallel host interface rather than SPI, USB, or PCI networking. Its integration of 10/100 controller and PHY functions allows the processor to communicate through a direct 16-bit bus and can reduce connector-level interface count. The 100-pin TQFP remains substantial, so component density should be compared against smaller SPI Ethernet controllers. A design trade-off is that the LAN9115 offers a broad embedded feature set and established ecosystem but requires careful 100-pin routing and validation.
Recommended
Recommended Products Summary
Engineering reference data for LAN9115-MT — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product |
|---|---|
| Brand | Microchip Technology |
| Package | 100-pin TQFP (14 x 20 mm) |
| Ethernet Class | 10/100 Ethernet |
| Physical Layer | Integrated 10/100 Base-T/TX PHY |
| Host Interface | 16-bit parallel, non-PCI |
| Nominal Supply Voltage | 3.3 V |
| Maximum Stated Clock Frequency | 25 MHz |
| Temperature Range | 0°C to 70°C |
| Verified Unit Price | USD 3.98 in supplied ZDI market record as of 2026-10-22 |
| Lifecycle Status | Active |
Key Differentiators
- Parallel non-PCI host architecture (vs W5100)
- Integrated 10/100 network interface (vs KSZ8001LI)
- Legacy embedded ecosystem alignment (vs LAN9210)
Design Notes
Start the layout from Microchip's LAN9115 datasheet reference schematic and recommended PCB pattern rather than reconstructing the Ethernet circuit from partial excerpts. Keep the 3.3 V distribution compact, place required decoupling at the supply pins, route the clock as a controlled signal, and preserve short paths between the PHY, magnetic-device network pins, and connector. The supplied material verifies a 3.3 V nominal supply and 25 MHz clock capability but does not provide trace widths or spacing values.
Budget host, controller, PHY, magnetic-device, and connector supplies separately; the verified 3.3 V value applies to LAN9115-MT and does not prove that every Ethernet subsystem component uses 3.3 V. Confirm absolute voltage limits and supply sequencing in the official datasheet. Decoupling capacitance, magnetic-device voltage, and local power-source impedance must come from the manufacturer reference design or verified component documentation, not estimation from this page.
Do not treat the integrated Base-T/TX PHY as a complete network connector. Ethernet magnetics, termination, isolation or common-mode requirements, RJ45 layout, and cable-interface protection must be designed according to the official reference circuit. A nominal 25 MHz maximum clock also does not remove the need to verify frequency tolerance, jitter, startup behavior, and the host timing assumptions required by the selected processor.
Preserve the integrity of the parallel host bus and clock even though the link operates at Ethernet rates. Route address, data, and control signals according to the host processor's bus timing, keep clock routing short, and avoid unnecessary series resistance unless the system timing analysis requires it. Cross-family parts such as LAN9117-MT or LAN9118-MT should not replace LAN9115-MT without a complete timing, pin, initialization, and firmware review.
Compliance Information
The verified excerpts do not state compliance or automotive-qualification status. The stated 0°C to 70°C range must not be interpreted as AEC-Q100 qualification.
