XR-T3588-89ES

Rev. 1.00

NOTICE

EXAR Corporation reserves the right to make changes to the products contained in this publication in order to im-
prove design, performance or reliability. EXAR Corporation assumes no responsibility for the use of any circuits de-
scribed herein, conveys no license under any patent or other right, and makes no representation that the circuits are
free of patent infringement. Charts and schedules contained herein are only for illustration purposes and may vary
depending upon a user's specific application. While the information in this publication has been carefully checked;
no responsibility, however, is assumed for inaccuracies.

EXAR Corporation does not recommend the use of any of its products in life support applications where the failure or
malfunction of the product can reasonably be expected to cause failure of the life support system or to significantly
affect its safety or effectiveness. Products are not authorized for use in such applications unless EXAR Corporation
receives, in writing, assurances to its satisfaction that: (a) the risk of injury or damage has been minimized; (b) the
user assumes all such risks; (c) potential liability of EXAR Corporation is adequately protected under the circum-
stances.

Copyright 1996 EXAR Corporation
User Manual November 1996
Reproduction, in part or whole, without the prior written consent of EXAR Corporation is prohibited.

Table of Contents

Rev. 1.00

OVERVIEW

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POWER REQUIREMENTS

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XR-T3588 DIGITAL INPUT AND XR-T3589
DIGITAL OUTPUT CONNECTIONS

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XR-T3588 LINE OUTPUT AND XR-T3589 LINE INPUT
CONNECTIONS

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TRANSMITTER AND RECEIVER POWER-DOWN

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Table 1. XR-T3588 Transmitter Selection

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Table 2. XR-T3589 Receiver Selection

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XR-T3589 GROUND POTENTIAL OFFSET TESTING

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ADDENDUM

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Table 3. List of Components

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Figure 2. Component Layout

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Figure 3. Circuit Diagram

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XR-T3588-89ES

...the analog plus company

XR-T3588/89

Evaluation System

Rev. 1.00

OVERVIEW

This unit is a 4.5 by 5.0 inch circuit board that simplifies the
evaluation of the XR-T3588 line driver and the XR-T3589
line receiver devices in a CCITT V.35 application. Its
features include dip switch selection of channel
power-down options, and provisions for applying the
ground potential offset voltage specified by the V.35 test
procedure to the receiver inputs.

Figure 1., Figure 2. and

Table 3. show the demo board component layout, circuit
diagram and list of components respectively.

POWER REQUIREMENTS

Supply voltages of +5.0V

5% for V

and -5.0V

for V

are applied to the board through banana jacks.

Both power sources should be well-regulated, and each
must be capable of supplying 250mA minimum. During
normal operation jumper E-1 must be installed, and
nothing is connected to the banana jack labeled OFFSET.

XR-T3588 DIGITAL INPUT AND XR-T3589 DIGITAL
OUTPUT CONNECTIONS

The TTL compatible transmitter inputs are the BNC
connectors mounted on the left side of the board that are
labeled TX1IN, TX2IN and TX3IN. Provisions are
included for installing input termination resistors R1, R2,
and R3 if required. These resistors (50 or 75

) are

needed only if a pulse generator with a low impedance
output and a fast rise time is used as a test signal source.
They are not required for TTL signals applied to the board
through short cables.

Likewise, the TTL compatible receiver outputs are the
BNC connectors labeled RX1OUT, RX2OUT and
RX3OUT.

XR-T3588 LINE OUTPUT AND XR-T3589 LINE INPUT
CONNECTIONS

The line connections are made to the six RJ-11
connectors or to the corresponding test point pairs that
are located on the right side of the board. The RJ-11s are
for connecting twisted pair cables, and the test points
provide a convenient means for viewing the output and
input signals differentially on an oscilloscope. From top to
bottom, the three transmitter outputs are labeled
TX1OUT, TX2OUT, and TX3OUT, and the three receiver
inputs are labeled RX1IN, RX2IN, and RX3IN. Note that
connectors are wired so that the "A" and "B" XR-T3588
output pins and the "A" and "B" XR-T3589 input pins go to
the same pin numbers on the RJ-11 connectors.
Therefore, a test cable must be wired in the same manner
to prevent a data inversion between the transmitter digital
input and the receiver digital output. (Telephone cables
typically contain a "twist" between modular connectors,
and will therefore give a data inversion.)

TRANSMITTER AND RECEIVER POWER-DOWN

The four-position DIP switch located in the center of the
board selects the logic state applied to the transmitter and
receiver channel enable pins. The top two sections
labeled TX, and the bottom two sections labeled RX are
for the XR-T3588 and XR-T3589 respectively. Table 1.
and

Table 2. show the powering options. Note that when

a DIP switch section is "OFF," a logic 1 is applied to the
corresponding IC pin.

XR-T3588

TX Switch Sections

Transmitter

SEL A

SEL B

1, 2, 3, On

Off

1, 2, On

Off

1 On

Off

All Off

Table 1. XR-T3588 Transmitter Selection

XR-T3588-89ES

Rev. 1.00

XR-T3589

RX Switch Sections

Receiver

SEL A

SEL B

1, 2, 3, On

Off

1, 2, On

Off

1 On

Off

All Off

Table 2. XR-T3589 Receiver Selection

XR-T3589 GROUND POTENTIAL OFFSET TESTING

The receiver ground potential offset test specified by
CCITT V.35 may be performed on the demo board. For

this test, jumper E-1 is first removed and then a DC
voltage in the range of

4V is applied between the GND

and OFFSET banana jacks.

ADDENDUM

Qty.

Value

Ref. Designators

Notes

51.1

, 1/4W, 1% Metal Film Resistor

R1,2,3,5,7,8,10,11,

13,14,16,17,19,20,22

10K, 2%, 5 Resistor, Thick-Film Network,

Panasonic

121

, 1/4W, 1% Metal Film Resistor

R6,9,12,15,18,21

3.92K, 1/4W, 1% Metal Film Resistor

R23

�

F, 16V, Electrolytic, Axial Lead,

5mm Dia., 2mm Spacing, Panasonic Type

NHE

C1,2

0.1

�

F, 63V, Z5U Dilectric,

Axial Lead, 0.1" Spacing, Panasonic

C3,4,5,6,7

4-Position DIP Switch, CTS

2 Pin Single-Row Header, Gold

Shorting Jumper for Above Header

Female BNC Connector, PC Mount

Connector for Digital I/O

6-Pin RJ-11 Connector

Connector for Line

Banana Jack (1 Black, 1 Red, 1 Blue, 1

Green)

GND, V

, V

, OFFSET

Connectors

Pins for Digital I/O and Ground Pads

14 pin DIP Socket

18 pin DIP Socket

Spacers to Elevate Board

4-40 x 5/16" Screws

To Attach Spacers

Table 3. List of Components

XR-T3588-89ES

Rev. 1.00

3 X 125

6 X 50

R12

0.1uF

TX1IN

TX2IN

TX3IN

GND

SELB

SELA

BIAS

I/P 1

I/P 2

I/P 3

REF

0/P 1A

O/P 1B

REF

O/P 2A

O/P 2B

REF

O/P 3A

O/P 3B

XR-T3588

R10

R13

�

+ 1

TX1OUT

TX2OUT

�

Optional Input

ermination Resistors

234

10K

R23

3.9K

�

TX3OUT

0.1uF

1 4

SELB

SELA

O/P 1

O/P 2

O/P 3

I/P 1A

I/P 1B

I/P 2A

I/P 2B

I/P 3A

I/P 3B

XR-T3589

SELB

SELA

SELB

SELA

T3588

T3589

RX1OUT

RX2OUT

RX3OUT

Green

fset

�

+ 1

RX1IN

RX2IN

RX3IN

�

R17

R18

R19

R20

R21

R22

R14

R15

R16

6 X 50

22uF

Red

+5V

Black

Ground

Blue

�5V

22uF

3 X 125

0.1uF

Jumper For Operation

Without Dc Of

fset

GND

Figure

2. Circuit Diagram

Электронный компонент: XR-T3588ES

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