Ethernet

PHY

TP1+

TP1-

TP2+

TP2-

TP3+

TP3-

TP4+

TP4-

RJ-45

Connector

ESDS314

ESDS314

9

ESDS312, ESDS314

www.ti.com

SLVSEG9B – MAY 2018 – REVISED SEPTEMBER 2018

Product Folder Links: ESDS312 ESDS314

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Copyright © 2018, Texas Instruments Incorporated

8 Application and Implementation

NOTE

Information in the following applications sections is not part of the TI component

specification, and TI does not warrant its accuracy or completeness. TI’s customers are

responsible for determining suitability of components for their purposes. Customers should

validate and test their design implementation to confirm system functionality.

8.1 Application Information

The ESDS314, ESDS312 devices are diode type TVS which is used to provide a path to ground for dissipating

surge and ESD events on high-speed signal lines between a human interface connector and a system. As the

current from surge or ESD passes through the TVS, only a small voltage drop is present across the diode. This

safe level for the protected IC.

8.2 Typical Application

Figure 13. ESDS314 Protecting the Ethernet 1Gbps Interface

8.2.1 Design Requirements

A typical operation for the ESDS314 would be protecting a high speed dataline similar to one shown in Figure 13.

In this example, the ESDS314 is protecting an Ethernet PHY's data lines that has a nominal operating voltage of

3.6 V. Many of the Ethernet interfaces that connect to long cables require protection against ±1 kV surge test

through a 42-Ω coupling resistor and a 0.5 µF capacitor, equaling roughly 24 A of surge current. Without any

input protection, if a surge event is caused by lightning, coupling, ringing, or any other fault condition, this input

voltage will rise to hundreds of volts for multiple microseconds, harming the device.

For Ethernet 1000Base-T (1Gbps), application design parameters listed in Table 1 are known.

Table 1. Design Parameters

DESIGN PARAMETER

VALUE

Signal range on differential data line pairs

0 to 3.6 V

Operating frequency

125 MHz