7491199112

Overview

The Würth Elektronik 7491199112 is a Surface Mount Device (SMD) Power over Ethernet (PoE) transformer designed for DC/DC converter applications within Switch Mode Power Supplies (SMPS). It features a WE-PoE series construction with an inductance of 127µH at 100kHz and a primary voltage range of 34V to 72V. The component provides 1500Vrms isolation and includes an auxiliary winding rated at 12V @ 15mA. Its physical dimensions are 13.46mm x 15.00mm with a maximum height of 12.70mm, operating within a temperature range of -40°C to 125°C.

Feature Summary

• Integrated auxiliary winding providing 12V output at 15mA for bias supply requirements
• High isolation rating of 1500Vrms ensuring safety compliance in PoE systems
• Optimized for high-temperature operation up to 125°C for robust industrial environments

Applications

• Power over Ethernet (PoE) powered devices
• DC/DC converter circuits in SMPS topologies
• Industrial networking equipment requiring high thermal stability

Procurement Notes

Verify the specific ordering suffix against the manufacturer's current datasheet to ensure correct packaging configuration, as variants exist for Tape & Reel, Cut Tape, and Digi-Reel formats. Confirm that the selected package matches the intended surface mount assembly process. Cross-reference the latest Product Change Notification (PCN) documents to account for any recent design or labeling updates issued by Würth Elektronik prior to finalizing procurement orders.

Selection Notes

Select this component when designing PoE interfaces requiring a 127µH inductance value and a wide input voltage range of 34V to 72V. The integrated auxiliary winding simplifies bias circuitry by eliminating the need for separate auxiliary power sources. Ensure the PCB footprint accommodates the 13.46mm x 15.00mm outline and verify that the system operates within the specified -40°C to 125°C ambient temperature limits for reliable performance.

Part Context

This part belongs to the Würth Elektronik WE-PoE series, which specializes in compact, efficient transformers compliant with IEEE 802.3 standards for Power over Ethernet applications. The series focuses on minimizing electromagnetic interference (EMI) while maintaining high efficiency in data and power transmission. The 7491199112 specifically targets flyback converter implementations where space constraints and thermal resilience are critical design parameters.

Replacement Considerations

Compatible alternative part numbers include those from the LM5070, LM5071, LM5072, LTC4267, TPS23750, and TPS23770 chipset families, provided they match the required electrical specifications and physical footprint.