Application Notes

Pulses interface modules provide the complete analog solution for

10Base-T multiport applications in various packages. Each module

includes low pass filters, isolation transformers, and may contain

common mode chokes. The 78Z034CNL contains data and pre-equal-

ization resistors on the transmit channel; and the receive

channel is terminated with impedance matching resistors.

Electrical Functions Include:

1. Impedance Matching -The low pass filters, in

conjunction with selected resistor values, effectively match

the impedance characteristics of the IC to those of the

transmission line. Precision wound inductors help control

passband impedances and lower return loss parameters. The

proper cut-off frequency minimizes insertion loss and delay

distortion while maximizing attenuation in the stopband.

2. EMI Suppression -The filter module is designed to control

signal harmonics and jitter, reflections, crosstalk interferences,

and common mode noise, which may contribute to radiated

and conducted emissions. High impedance common mode

chokes significantly minimize their effects.

3. Equipment Isolation - The transformer is designed to

withstand 2000 Vrms, ensuring protection from static charge

on the twisted pair line. Each module is fully tested to ensure

compliance with IEEE 802.3 1993 standards.

In some applications, such as multiport repeaters, many channels are

in close proximity. User compliance with FCC/CISPR22 Class B

requirements can be achieved by applying rigorous design guidelines

to suppress noise mechanisms. Attention to high frequency signal

paths, good PCB grounding techniques, and component placements

are critical.

A typical Network Interface Card Application is featured below.

UTP

DB-15

Vcc

AUI

XFMR

AUI

Port

10 Base-T

Transceiver

61.9

Ω

422

Ω

61.9

Ω

Receive

Filter

MDI

Port

RJ-45

TXD+

CD

XMT

XMT

XMT

RCV

RCV

Transmit

Filter

78Z034CNL

422

Ω

TD+

TD-

RD+

RD-

XMT

XMT

XMT

CD

RCV

RCV

49.9

Ω

49.9

Ω

TXP+

TXD-

TXP-

RXI+

RXI-

Vcc

Typical Application Circuit

10BASE-T THROUGH HOLE

INTERFACE MODULES

For 802.3 10Base-T LAN Applications

Note: Modules are packaged in tubes.

www.pulseeng.com

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E104.F (8/10)

For More Information:

Pulse Worldwide

Headquarters

12220 World Trade Dr.

San Diego, CA 92128

U.S.A.

www.pulseeng.com

Tel: 858 674 8100

Fax: 858 674 8262

Pulse Europe

Zeppelinstrasse 15

D-71083 Herrenberg

Germany

Tel: 49 7032 7806 0

Fax: 49 7032 7806 135

Pulse China Headquarters

B402, Shenzhen Academy of

Aerospace Technology Bldg.

10th Kejinan Rd.

High-Tech Zone

Nanshan District

Shenzen, PR China 518057

Tel: 86 755 33966678

Fax: 86 755 33966700

Pulse North China

Room 2704/2705

Super Ocean Finance Ctr.

2067 Yan An Rd. West

Shanghai 200336

China

Tel: 86 21 62787060

Fax: 86 2162786973

Pulse South Asia

135 Joo Seng Rd.

#03-02

PM Industrial Bldg.

Singapore 368363

Tel: 65 6287 8998

Fax: 65 6287 8998

Pulse North Asia

3F, No. 198

Zhongyuan Rd.

Zhongli City

Taoyuan County 320

Taiwan R. O. C.

Tel: 886 3 4356768

Performance warranty of products offered on this data sheet is limited to the parameters specified. Data is subject to change without notice. Other brand and product names

mentioned herein may be trademarks or registered trademarks of their respective owners. © Copyright, 2010. Pulse Engineering, Inc. All rights reserved.