LP1197NL PoE Magnetics Specifications

The LP1197NL is a 10/100Base-TX single-port PoE LAN transformer module designed for Ethernet devices that require both reliable data transmission and Power over Ethernet (PoE) support. Built with an open-frame construction and optimized for surface-mount (SMT) assembly, LP1197NL integrates isolation transformers and filtering components to ensure signal integrity, EMI suppression, and safe power delivery over twisted-pair Ethernet cables.

Compliant with IEEE 802.3 Ethernet specifications and featuring 1500 Vrms isolation, LP1197NL is widely used in VoIP equipment, SOHO networking devices, LAN-on-Motherboard (LOM) designs, Ethernet switches, and PoE-enabled embedded systems.

Electrical Specifications (@ 25 °C)

Key Features of Power over Ethernet Transformer

• 10/100Base-TX PoE LAN magnetics module, single port
• Designed for PoE Ethernet applications
• 1:1 turns ratio for both transmitter and receiver
• Open-frame construction for compact, cost-effective designs
• Excellent signal integrity with low insertion loss and high return loss
• High common-mode noise rejection (DCMR) for improved EMI performance
• 1500 Vrms isolation voltage for safe PoE operation
• Surface-mount package, tape & reel supplied
• RoHS compliant, lead-free
• UL certified (File No. E484635)
• Supports automated SMT reflow assembly (up to 250 °C peak)

LP1197NL PoE LAN Transformer Design Advantages

Unlike standard non-PoE LAN transformers, the LP1197NL is designed to handle DC bias currents associated with PoE power delivery while maintaining stable magnetic performance. Its transformer structure minimizes core saturation, ensuring:

• Stable Ethernet link under PoE load
• Reduced packet loss and signal distortion
• Improved EMC/EMI compliance in PoE systems

This makes LP1197NL suitable for PoE-powered VoIP phones, IP cameras, access points, and embedded Ethernet devices.

PCB Layout & Assembly Notes

• Place the LP1197NL close to the Ethernet PHY to minimize trace length.
• Route TX/RX differential pairs with controlled impedance.
• Maintain adequate creepage and clearance to preserve isolation performance.
• Suitable for lead-free reflow soldering, with a maximum reflow temperature of 250 °C for 5 seconds.
• Ensure proper thermal design for PoE current handling.

Frequently Asked Questions about LP1197NL PoE Magnetics

The LP1197NL is a reliable, PoE-ready 10/100Base-TX LAN transformer module designed for compact, cost-effective Ethernet devices. With strong isolation, excellent EMI performance, and proven compliance, it is an ideal choice for VoIP, SOHO, and embedded PoE networking applications.

Q1: Is LP1197NL suitable for PoE applications?

A: Yes. LP1197NL is specifically designed for PoE Ethernet systems, supporting DC bias current while maintaining signal integrity.

Q2: What Ethernet speeds are supported?

A: LP1197NL supports 10Base-T and 100Base-TX Fast Ethernet applications.

Q3: Does this module provide sufficient isolation for PoE?

A: Yes. It provides 1500 Vrms isolation, meeting common Ethernet and PoE safety requirements.

Q4: Is the part compatible with automated SMT assembly?

A: Yes. The module is supplied in tape & reel packaging and supports standard SMT reflow processes.