LAN8671B1-E/U3B Microchip Integrated Circuit (Quad Flat No-Lead) In Stock
Microchip LAN8671B1-E/U3B is a 10BASE-T1S single-pair Ethernet PHY transceiver with RMII interface in a 24-pin QFN package. It supports multi-drop bus topology at 10 Mbps over a single twisted pair, targeting automotive and industrial networks. Available from stock with worldwide shipping.
- Manufacturer
- Microchip
- Package
- Quad Flat No-Lead
- Pin Count
- 25
- Lifecycle
- OBSOLETE
- Datasheet
- LAN8671B1-E/U3B Datasheet PDF
- Category
- Integrated Circuit
- Temp Range
- -40.0°C to 125.0°C
- RoHS
- Compliant
- Lead Time
- 3–7 business days
- Shipping
- DHL Express · Worldwide
Key Features
- 10BASE-T1S PHY supporting multi-drop bus topology with up to 8 nodes on a single twisted-pair cable at 10 Mbps
- RMII interface at 50 MHz simplifies integration with microcontrollers and industrial SoCs without an external clock source
- Compact 24-pin QFN (4 mm x 4 mm) package with exposed thermal pad minimizes PCB area in space-constrained designs
- AEC-Q100 qualified for automotive applications with an operating temperature range of -40 °C to +125 °C
Applications
LAN8671B1-E/U3B is designed for automotive body control modules, HVAC systems, and industrial sensor networks that require low-cost single-pair Ethernet connectivity under the 10BASE-T1S standard. Its multi-drop capability connects up to 8 nodes on one cable segment without switches, reducing wiring harness weight and cost in vehicle and factory floor applications. The RMII interface makes it straightforward to pair with popular ARM-based MCUs and industrial Ethernet controllers in embedded networking designs.
Specifications
| YTEOL | 0 |
| Data Rate | 10000Mbps |
| JESD-30 Code | S-PQCC-N24 |
| JESD-609 Code | e3 |
| Number of Functions | 1 |
| Number of Transceivers | 1 |
| Package Body Material | PLASTIC/EPOXY |
| Package Equivalence Code | LCC24,.16SQ,20 |
| Package Shape | SQUARE |
| Package Style | CHIP CARRIER, HEAT SINK/SLUG, VERY THIN PROFILE |
| Supply Voltage-Nom | 3.3V |
| Surface Mount | YES |
| Telecom IC Type | ETHERNET TRANSCEIVER |
| Terminal Finish | Matte Tin (Sn) |
| Terminal Form | NO LEAD |
| Terminal Pitch | 0.5mm |
| Terminal Position | QUAD |
| Package | Quad Flat No-Lead |
Compliance & Regulatory
| RoHS Status | Compliant |
| Lead-Free | Yes (Pb-Free) |
| HTS Code | 8542.39.00.01 |
Alternate & Equivalent Parts
No known alternates. Submit an RFQ and our team can suggest alternatives.
Frequently Asked Questions
How many nodes can share a single cable segment when using LAN8671B1-E/U3B in multi-drop mode, and at what data rate?
In 10BASE-T1S multi-drop mode, LAN8671B1-E/U3B supports up to 8 nodes on a single twisted-pair bus segment operating at 10 Mbps. This eliminates the need for Ethernet switches in small node-count networks, significantly reducing wiring complexity and cost in automotive body networks and industrial sensor clusters.
What host interface does LAN8671B1-E/U3B use, and what clock frequency does it require from the MCU?
LAN8671B1-E/U3B uses a Reduced Media Independent Interface (RMII) operating at 50 MHz. This interface requires the host microcontroller or SoC to supply or share a 50 MHz reference clock, allowing designers to integrate the PHY with mainstream ARM Cortex-M and automotive-grade MCUs without adding a dedicated external oscillator in most system configurations.
What is the operating temperature range of LAN8671B1-E/U3B, and is it suitable for under-hood automotive environments?
LAN8671B1-E/U3B is rated for -40 °C to +125 °C operation and is AEC-Q100 qualified, meeting the thermal and reliability requirements for under-hood automotive environments. The 24-pin QFN package with an exposed thermal slug helps dissipate heat in tight enclosure designs where ambient temperatures can approach 125 °C during prolonged operation.
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