Cermetek DataSheet for product XE2420

XE2420

March 2002

2400 BPS Surface-Mountable Integrated Sealed-Hybrid Modem

Description

Features

Xecom’s XE2420 provides a complete 2400 BPS

* Small Size: The HyPLCC™ measures less than 1

modem into an inexpensive miniature, surface-mount

inch by 1inch square and 0.290 inches thick

package. Xecom’s new HyPLCC™ package (Hybrid

* Surface-mountabile: The HyPLCC™ package is

PLCC) makes it possible to meet the conflicting goals

equivalent to a 68-Pin PLCC device.

of small size, low cost and surface-mountability. The

* Data transfer at 2400, 1200 and 300 BPS using

XE2420 targets remote monitoring applications in

V.22bis, V.22, V.23, V.21, Bell 202, Bell 212A, and

industrial, commercial and residential locations

Bell 103 Protocols

As a complete modem, the XE2420 includes not only

* Modem Control and Configuration via industry

all modem circuitry but also user transferrable FCC

standard AT Commands.

Part 68 Registration and UL60950 recognition. This

* Supports external shared line features permitting

allows the XE2420 to be safely integrated into your

unobtrusive sharing of a local telephone line.

embedded application.

* Complete integrated DAA includes, Ring Detect,

Xecom’s new HyPLCC™ package infuses the XE2420

Loop Current Holding Circuit, Hook Switch. Metalic

with both its small size and surface mountability. The

Surge Protection, and Telephone Line Transformer

HyPLCC package allows complex hybrid circuits to fit

* User Transferrable FCC Part 68 Registration

the 68-Pin PLCC footprint. The HyPLCC™ package

* UL60950 Recognition

provides a completely sealed enviroment protecting

the XE2420 during assembly and board cleaning

* Low Power operation, 330 milliWatt; Power down

operations.

operation less than 1 microWatt

XE2420 BLOCK DIAGRAM

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XE2420

XE2420 Mechanical Specifications

(TOP)

.050”

45 O

Inches

Millimeters

Dimension

Min

Typ

Max

Min

Typ

Max

0.280

0.285

0.290

7.11

7.24

7.37

0.985

0.990

0.995

25.02

25.15

25.27

0.950

0.955

0.960

24.13

24.26

24.38

0.910

0.920

0.930

23.11

23.37

23.62

0.045

0.050

0.055

1.15

1.27

1.40

0.695

0.700

0.705

17.65

17.78

17.91

0.395

0.400

0.405

10.03

10.16

10.29

i(radius)

0.015

0.020

0.025

0.13

0.25

0.38

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XE2420

XE2420 Pin Configuration

/DCD

/CTS

RESET

/DSR

RING

/RTS

N/C

/DTR

TIP

/RXD

N/C

/TXD

TOP

N/C

/RI

HI3

GND

HI1

N/C

EECL

HI2

EEDT

Vcc

Vui

Pin Descriptions

NAME

DESCRIPTION

/DCD

/DCD is an active low output from the modem. The AT&C command controls when the

XE2420 asserts /DCD.

/CTS

/CTS is an active low output from the modem. The modem asserts /CTS to indicate that it can

accept data from the terminal equipment on /TXD.

RESET

RESET is an active high input which intiates a modem hardware reset. RESET must be active

for a minimum of 100 milliseconds for a proper modem reset sequence. No external reset is

required; if none is used the RESET signal should be left open.

/DSR

/DSR is an active low output from the modem. The AT&S command controls when the XE2420

asserts /DSR.

/RTS

/RTS is an active low input to the modem. /RTS indicates to the modem that the host has data

to send.

/DTR

/DTR is an active low input to the modem. The AT&D command determines how the modem

will interpret activity on /DTR.

/RXD

/RXD provides the path for received data and modem responses to be sent from the modem to

the host terminal equipment.

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XE2420

XE2420 Pin Descriptions (continued)

NAME

DESCRIPTION

/TXD

/TXD provides the path for transmitted data and modem commands to be passed from the host

terminal equipment to the modem.

/RI

The /RI signal reports on the presence of an incoming ring signal. When a ring occurs across

Tip and Ring, the /RI output toggles at the ring frequency. The /RI output is powered by Vui

and therefore operates even when VCC is removed from the modem.

Ground

Ground provides the reference voltage for all host interface signals.

N/C

No internal connection

EECL

EECL provides the clock to the optional external non-volatile memory. The XE2420 requires

a serial 8 by 256 Byte EEPROM for telephone number storage. If the non-volatile memory is

not used, EECL should remain unconnected.

EEDT

EEDT provides the serial data connection for the optional, external non-volatile memory. The

XE2420 requires a serial 8 by 256 Byte EEPROM for telephone number storage. If the non-

volatile memory is not used, EEDT should remain unconnected.

VCC

VCC provides 5 volt power to the modem. The RI output is not powered by VCC but by Vui.

Vui

Vui provides uninterrupted power to the XE2420 ring detect circuit. Placing 5 volt power on

Vui insures that the /RI ouput will operate when VCC is removed from the modem.

HI2

HI2 is one of the four hardware hooks for connecting shared line features to the XE2420.

HI2 interfaces to the 911 Interrupt circuit.

This circuit detects changes in the loop current

when an extension handset is lifted as when making an emergency call. The system host

should immediately abort the modem connection to permit the user to complete their call.

See the Application Note on Page 10 of this data sheet to see how these line monitoring

circuits interface with the XE2420.

CD provides another of the four hardware hooks for connecting shared line features to the

XE2420. CD interfaces to the Connect Dectect circuit. Connect Detect allows the system

host to check the status of the telephone line before going off-hook to initiate a call. If the

phone line is in use,the host can delay its call until the telephone line is free. See the

Application Note on Page 10 of this data sheet to see how these line monitoring circuits

interface with the XE2420.

HI1

HI1 is one of the four hardware hooks for connecting shared line features to the XE2420.

HI1 interfaces to the 911 Interrupt circuit.

This circuit detects changes in the loop current

when an extension handset is lifted as when making an emergency call. The system host

should immediately abort the modem connection to permit the user to complete their call.

See the Application Note on Page 9 of this data sheet to see how these line monitoring

circuits interface with the XE2420.

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XE2420

XE2420 Pin Descriptions (continued)

NAME

DESCRIPTION

HI3

HI3 is one of the four hardware hooks for connecting shared line features to the XE2420.

HI3 interfaces to the 911 Interrupt circuit.

This circuit detects changes in the loop current

when an extension handset is lifted as when making an emergency call. The system host

should immediately abort the modem connection to permit the user to complete their call.

See the Application Note on Page 10 of this data sheet to see how these line monitoring

circuits interface with the XE2420.

N/C

No internal connection, To prevent damage in case of voltage surges on the telephone line, we

recommend that nothing be connected to this pin.

N/C

No internal connection, To prevent damage in case of voltage surges on the telephone line, we

recommend that nothing be connected to this pin.

Tip

The Ring and Tip signals provide modem the connection to the telephone line. FCC Part 68

Rules require a 1500 volt isolation barrier between the telephone line and all other circuits.

This isolation must be preserved throughout the system.

The telephone company places a DC “Battery” voltage across Tip and Ring on all public switched

telephone lines. The XE2420 will operate regardless of the polarity of this “Battery” voltage.

The “Battery” voltage drives up to 100 milliamps of DC loop current.

UL60950 requires minimum creepage and clearances distances be maintained between the

Tip and Ring traces and all other circuits. Clearance is the shortest distance between conductive

circuits; creepage is the distance between conductive surfaces along the surface

N/C

No internal connection, To prevent damage in case of voltage surges on the telephone line, we

recommend that nothing be connected to this pin.

Ring

The Ring and Tip signals provide modem the connection to the telephone line. FCC Part 68

Rules require a 1500 volt isolation barrier between the telephone line and all other circuits.

This isolation must be preserved throughout the system.

The telephone company places a DC “Battery” voltage across Tip and Ring on all public switched

telephone lines. The XE2420 will operate regardless of the polarity of this “Battery” voltage.

The “Battery” voltage drives up to 100 milliamps of DC loop current.

UL60950 requires minimum creepage and clearances distances be maintained between the

Tip and Ring traces and all other circuits. Clearance is the shortest distance between conductive

circuits; creepage is the distance between conductive surfaces along the surface.

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XE2420

XE2420 Soldering Instructions

The XE2420 is subject to damage if over-exposed to heat during solder reflow operations. Following the

soldering instructions below will ensure that the process of soldering the module to the board does not damage the

modem. The XE2420 must not be exposed to direct Infrared (IR) heating. If your process includes direct IR

heating, you must shield the XE2420 from the infrared rays.

Maximum Temperature

220 O C

MaximumTimeat220 O C

20 Seconds

Maximum Time above Eutectic (180 O C)

90 Seconds

MaximumPreheatDwellTime

180 Seconds

Maximum Recommended Solder Temperature Profile

220 O C

180 O C

150 O C

-20 sec-

--------------------------------180secmax---------------------

max

----- 90 sec max -----

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XE2420

XE2420 Electrical Specifications

Parameter

Min

Typ

Max

Units

Comments

VCC

4.75

5.25

Volts

ICC

On Line

ICC

idle

Vui

4.75

5.25

Volts

Iui

µ a

No Ring Signal Present

Ring Voltage Detected

150

RMS

Type B Ringer

Ring Frequency Detected

15.3

Type B Ringer

Connect Detect Sensitivity

Volts DC

Battery Voltage level detected by

circuit shown on Page 10

Handset Interrupt Detection

1.0

Volts DC

Change in Battery Voltage

detected by circuit shown on

Page 10

Telephone Loop Current

100

Line Impedance

600

Ohms

Data Transmit level

-12

-10

-9

dBm

DTMF Transmit Level

-2.5

dBm

Avg over 3 second interval

Voh

2.4

Volts

Vol

0.4

Volts

Vih

2.0

VCC+0.3

Volts

Vil

-0.3

0.8

Volts

XE2420 ABSOLUTE MAXIMUM RATINGS

Storage Temperature

-25 O C to +85 O C

Operating Temperature Range 1

0 O C to +70 O C

Maximum Time Above Eutectic (183 O C)

90 seconds

Preheat Dwell Time

120 to 180 seconds

The XE2420 can be ordered with an Operating Temperature of -40 O C to +85 O C at extra cost. Order XE2420-ITR or

to specify Industrial Temperature Range (ITR).

XECOM

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XE2420

XE2420 Typical Application Schematic

+5 Volts

NM24C04

20K

VCC

XE2420

SCL

Reset

VSS

SDA

EECL

EEDT

/TXD

RJ11

/TXD

/RXD

FB1

/RTS

RING

16C550

/RI

UART

/DSR

FB2

/DCD

TIP

/CTS

/DTR

+5 Volts

Vcc

Battery

Vui

Gnd

Notes:

FB1 and FB2 are ferrite beads which may be required for EMI filtering in your system. Without these

components you may experience unintended radiation when the telephone cable is attached to your system.

We recommend selecting components such as the TDK ACB2012L-120 which provide a minimum of 100

ohms of impedence at frequencies above 100 MHz.

2. C1 and C2 are high-voltage capacitors which may be required for EMI filtering in your system. Without these

components you may experience unintended radiation when the telephone cable is attached to your system. We

recommend selecting components such as the Panasonic ECKDRS471. This 470 pfd, 3000 volt capacitor will

direct the high frequency harmonics to the system ground. These capacitors must be rated at a minimum of 1500

volts to maintain the isolation required by FCC Part 68 Rules.

3. The Battery applied to Vui allows the XE2420’s Ring Indicate output to remain active even when the modem

itself is powered down. If this power-down mode is not required for your application, Vui should be tied to

VCC.

4. The EEPROM, NM24C04, provides for non-volatile storage of telephone numbers using the AT&Z command.

The EEPROM must be programmed using the Diplomat™ Utility from Zilog Inc.

Diplomat™ is a trademark of Zilog Inc.

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XE2420

Application Note: Using a 68-Pin PLCC Socket

The XE2420 can be inserted into a socket for a 68-pin PLCC device. The HyPLCC package uses only 24 pins; 15

on one side and 9 on the opposite side. Allignment within the socket is critical for all pins of the XE2420 to

make contact with the appropriate pins of the PLCC socket. The drawing below illustrates how the XE2420 can be

inserted into the 68-pin PLCC socket.

XE2420

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XE2420

Application Note: XE2420 Shared Line Feature

For applications where the XE2420 shares a telephone line with a telephone handset, Xecom has provided four

hardware hooks for connecting two monitoring circuits. These circuits monitor the status of the telephone line to

prevent the modem from interfering with a voice call.

The Connect Detection Circuit monitors the telephone loop voltage when the modem is not in use. This allows the

system host to check the status of the telephone line before initiating a call. The ConDetect signal will be be high

when the phone line is available but goes low to indicate that the telephone line is in use.

The Handset Interupt or 911 Interrupt circuit monitors loop current while the modem is in the off-hook state. This

circuit detects the change in loop current which occurs when a handset on the shared telephone line is lifted. The

HSInterrupt output will go low momentarily if the handset is lifted during data communications. The system host can

then immediately abort the modem connection and permit the user to complete their call.

Parts List for Shared Line Feature Application Note

Reference

Designation

Qty

Description

Designation

Qty

Description

C1, C2

Cap. 470 pfd 2600V

Resistor, 56K 5%

Cap. 10 ufd 20% 16V

Resistor, 33K 5%

Cap. 1 Ufd, 20% 10V

Resistor, 402K 5%

F1, F2

PTC, TR600-150

R10

Resistor, 1M 5%

FB1, FB2

Ferrite, ACB2012L-120

R11

Resistor, 1.5K 5%

Trans. FMMT3904

R12

Resistor, 20K 5%

R1, R2

Resistor, 10M 5%

R13

Resistor, 100K 5%

R3, R5, R6

Resistor, 200K 1%

U1, U2

OP Amp, TLC271CD

Resistor, 280K 1%

Opto-coupler, PS2705-1

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XE2420

XE2420 AT Commands

The XE2420 uses "AT" commands for configuration and

Command Buffer -

No more than 36 characters,

control. This section describes use of the AT command

including the AT prefix, may be loaded into the com-

format and lists the AT commands, Registers and Result

mand buffer.

If the command buffer overflows, the

codes. XE2420 "AT" commands have two operational

modem issues an "ERROR" result code and commands

modes; Command Mode and Data Mode.

are not executed.

Data Mode: The XE2420 enters data mode after it

Command Line Editing -

The backspace edits a

connects with a remote modem and issues the appropri-

command line before it is executed. The backspace key,

ate result code. In the Data Mode the modem sends all

(Control and H simultaneously on some systems), erases

data presented on Transmit Data (/TXD) to the remote

the previous character in the command line. Register S5

modem and puts data from the remote modem onto

allows the user to select a character other than a back-

Received Data (/RXD). When the modem exits data

space to edit the command line.

mode, it issues a "NO CARRIER" result code.

Re-Execute Last Command - The A/ command causes

Command Mode: The XE2420 enters command mode

the modem to re-execute the last command line. This is

on power-up, reset, a lost connection, or receipt of the

the only command which does not require the "AT"

escape code.

In command mode the modem accepts

prefix.

commands from the host on transmit data. Appropriate

result codes are returned on received data.

Omitted Parameters - Most commands include a pa-

rameter which determines how the functions will be set.

Command Line Format

When the command parameter is omitted from the

Command lines issued to the modem follow a strict

command string, it is assumed to be a 0.

format. Each command begins with the prefix AT. The

command line is stored in the command buffer and

Escape Characters - A 3 character escape sequence

executed upon receipt of a carriage return.

Until

maybe entered while in data mode to switch the modem

executed, the command line can be edited with the

into command mode while on line. The escape charac-

backspace key.

ter, set by Register S2, must be entered 3 times in

succession to execute the escape. An AT command must

Command Prefix - Each command, except

the A/

then be enterred within the period defined by S12 to

command, begins with the AT prefix. The "A" and "T"

enter the command mode. The default escape sequence

may be either both upper case or both lower case but

is "+++."

cannot be of different cases. The prefix identifies the

speed and parity of the commands sent to the modem by

Result Codes - The modem issues a result code after

the host. Speed is determined by measuring the width of

each action. Result codes may be provided as full words,

the incoming bits. Parity is determined by comparing the

one or two digit numeric codes, or may be disabled all

parity bit of the "A" and the "T."

together. Each result code ends with a carriage return

when numeric result codes are chosen. When full word

Command Line - Commands may be strung together in

result codes are chosen, a Line Feed and Carriage Return

a single command line of up to 36 characters. Com-

preceed and follow each result code.

mands are executed in the sequence they appear. Spaces

may be inserted into the command line but do not fill

space in the command buffer. A carriage return termi-

nates the command line and causes the commands to be

executed.

character other than a carriage return to terminate the

command line.

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XE2420

XE2420 AT Commands

An asterisk indicates the factory default

A - Answer Command -

Xn - Result Code Set -

n=0

Responses 0-4

Bn - Select Communications Standard

n=1 Responses 0-5 & 10

n=0 Selects CCITT standards

n=2 Responses 0-6 & 10

n=1

Selects Bell standards*

n=3 Responses 0-5, 7 & 10

n=2

Selects V.23/Bell 202 (see S37)

n=4 Responses 0-7 & 10*

D - Dial Command -

&Cn - DCD Operation

0-9, A-D, #, * = Dialing Digits

n=0 DCD is forced active*

P = Pulse dial

n=1 DCD indicates a valid carrier signal

T = Tone dial

&Dn - DTR

R = Connect as an answering modem

W = Wait for dial tone

n=0

DTR is ignored*

= Pause for the duration of S8

n=1 When the modem is on-line DTR off switches it to

@ = Wait for silence

the command mode and issues OK response.

= Switch hook flash

n=2 Modem disconnects if the host revokes DTR.

;

= Return to the command state

n=3

The modem performs a soft reset when DTR is

S=n = Dial Stored Number n

revoked.

En - Command Echo

&F - Reset Factory Defaults

n=0 Do not echo commands

&Gn - Guard Timer -

n=1 Enable command echo*

n=0

None *

Hn - Switch Hook Control -

n=1 550 Hz Guard Timer

n=0 Switch hook relay opens

n=2

1800 Hz Guard Timer

n=1 Switch hook relay closes

&Sn - Data Set Ready

n=0

Data Set Ready Forced Active *

In - Modem Identification

n=1

Data Set Ready on at Start of Modem handshake

Mn - Speaker Activity -

&Z=x - Store dialing string x

n=0 Speaker off

n=1 Speaker on until carrier received*

%En - Automatic Retrain

n=2 Speaker remains on

n=0 Automatic Retrain Disabled

n=3 Speaker on after dialing until carrier is detected.

n=1 Automatically retrain on poor signal quality *

On - On Line

\Nn - Data Buffering

n=0 Return On Line with no retrain*

n=0 Data Bufferred

n=1

Direct Mode no data buffering *

n=1 Initiate retrain while returning On line.

\Qn - Flow Control

Qn - Responses

n=0

Flow Control Disabled

n=0 Send responses *

n=1

XON/XOFF Flow Control

n=1 No Responses

n=2

CTS Flow Control

Sr? - Interrogate Register -

n=3

RTS/CTS Flow Control *

Sr=n - Set Register Value -

n=4

DCE to DTE XON/XOFF Flow Control

Vn - Result Codes -

n=0

Numeric Result Codes

n=1

English Word Result Codes*

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XE2420

XE2420 Modem Registers

Answer on nth Ring: S0 sets the modem to

Wait for Carrier after Dialing: S7 determines how long

automatically answer on the nth ring. Setting S0 to 0

the modem waits for a valid carrier signal after dialing is

disables automatic answer.

completed.

Range:

0 to 255

Range:

1 to 255

Units

Rings

Units

Seconds

Default

Ring Count: S1 is a read-only register showing the

Comma Pause Time: S8 defines the duration of the

number of rings detected. If a ring is not detected

pause initiated by a comma in the dialing string. The pause

within 8 seconds, S1 is reset to zero.

is generally used when waiting for a second dial tone.

Range:

0 to 255

Range:

1 to 255

Units

Rings

Units

Seconds

Default

Escape Character: S2 determines the ASCII escape

Carrier Detect Response Time: S9 establishes the

character. Values of 0-127 select valid ASCII escape

length of time the remote modem's carrier must be present

characters; values from 128 to 255 disable the escape

to be recognized as valid.

sequence.

Range:

1 to 255

Range:

0 to 255

Units

0.1 Seconds

Units

ASCII Character

Default

43 (+)

S10

Carrier Off Disconnect Delay : S10 selects how long

Line Termination Character: S3 determines the

carrier must be lost before the modem disconnects. Note:

ASCII character which will terminate commands and

If S10 is smaller than the value of S9 or S10 is set to 255,

modem responses.

the modem will not automatically disconnect on loss of

Range:

0 to 127

carrier.

Units

ASCII Character

Range:

1 to 255

Default

13 (Carriage Return)

Units

0.1 Seconds

Default

Line Feed Character: S4 sets the ASCII character

to act as a line feed character in modem responses.

S11

Tone Dialing Speed: S11 sets the duration and spacing

Range:

0 to 127

of the dialing tones. S11 does not affect the pulse dialing

Units

ASCII Character

rate.

Default

10 (Line Feed)

Range:

50 to 255

Units

1 Millisecond

Backspace Character: S5 defines the ASCII

Default

character used as a backspace to edit the command

line.

S12

Escape Code Guard Timer: S12 sets the escape

Range:

0 to 127

sequence guard timer. If characters are received before or

Units

ASCII Character

after the escape sequence, within the guard timer, the

Default

8 (Back Space)

modem aborts the escape attempt and remains in data

mode.

Dial Tone Wait Time: S6 determines how long the

Range:

0 to 255

modem waits for dial tone before dialing begins. The

Units

0.02 Seconds

Dial Tone Wait Time cannot be set to less than two

Default

seconds.

Range:

2 to 255

Units

Seconds

Default

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XE2420

XE2420 Modem Registers continued

S28

Inactivity Timer: S28 determines how long the mo-

S37

Maximum Line Data Rate: S37 sets the maximum

dem wil remain on line with not data flowing. A 0 in

line data rate or modulation technique that the XE2420

this register disables the inactivity time out.

will support for any connection.

Range:

0-255

Units

Minutes

Value

Communications Supported

Default

Maximum Data Rate determined by the

autobaud function of the AT Command

S29

Hook Flash Time : S29 determines the the amount

Connect using V.23, asymmetrical modem

of time the modem will go on-hook when a hook

modulation, 1200/75 BPS

switch flash is called for.

Connect using Bell 202, asymmetrical

Range:

0-255

modulation, 1200/150 BPS

Units

0.02 Seconds

V.21, Bel 103, 300 BPS

Default

Reserved

V.22, Bell212A 1200 BPS

V.22bis 2400 BPS

XE2420 Modem Responses

Digits

Verbose

Description

Successfully executed command line

CONNECT

300 bps connection

RING

Ring signal detected

NO CARRIER

Carrier not detected/lost

ERROR

Error in command line

CONNECT 1200

1200 bps connection

NO DIAL TONE

No dial tone detected

BUSY

Busy signal detected

NO ANSWER

5 second silence not detected

CONNECT 2400

2400 bps Connection

CONNECT 1200TX/75RX

V.23 Connection transmitting at 1200 BPS

CONNECT 75TX/1200RX

V.23 Connection transmitting at 75 BPS

CONNECT 1200TX/150RX

Bell 202 Connection transmitting at 1200 BPS

CONNECT 150TX/1200RX

Bell 202 Connection transmitting at 150 BPS

XECOM

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XE2420

FCC Instructions

The XE2420 complies with part 68 of the FCC Rules and Regulations. With each device shipped, there is a label which con-

tains, among other information, the FCC Registration Number and Ringer Equivalence Number (REN) for this product. You

must, upon request, provide this information to your telephone company.

The mounting of this device in the final assembly must be made in such a manner as to preserve the high voltage protection be-

tween the TIP/RING Connection and the rest of the system. Typically, this may be accomplished by maintaining a minimum

spacing 100 mils between the TIP/RING Traces to the RJ-11C Jack and low voltage portion of the system. No additional cir-

cuitry may be attached between TIP/RING and the telephone line connection, unless specifically allowed in the rules.

The REN is useful to determine the quantity of devices you may connect to a telephone line and still have all of these devices

ring when the number is called. In most, but not all areas, the sum of the RENs of all devices connected to one line should not

exceed five (5.0). To be certain of the number of devices you may connect to the line, as determined by the REN, you should

contact the local telephone company to determine the maximum REN for you calling area.

If your system causes harm to the telephone network, the telephone company may discontinue service temporarily. If possible,

they will notify you in advance. If advance notification is not practical, you will be notified as soon as possible.

Your telephone company may make changes in its facilities, equipment, operations or procedures that could affect proper func-

tioning of your equipment. If they do, you will be notified in advance to give you an opportunity to maintain uninterrupted tele-

phone service.

If you experience trouble with this device, please contact XECOM at (408) 945-6640 for information on obtaining service or

repairs. The telephone company may ask you to disconnect this device from the network until the problem has been corrected

or until you are sure that the device is not malfunctioning.

The device may not be used on coin service lines provided by the telephone company (this does not apply to private coin tele-

phone applications which use standard telephone lines). Connection to party lines is subject to state tariffs.

XECOM

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XE2420

Terms of Sale

Devices sold by XECOM are covered by the warranty provisions appearing in its Terms of Sale only. XECOM makes no war-

ranty, express, statutory, implied, or by description regarding the information set forth herein, or regarding the freedom of the

described devices from patent infringement. XECOM makes no warranty of merchantability or fitness for any purposes.

XECOM reserves the right to discontinue production and change specifications and prices at any time and without notice. This

product is intended for use in normal commercial applications. Applications requiring extended temperature range, unusual en-

vironmental requirements, or high reliability applications, such as military, medical life-support or life-sustaining equipment, are

specifically not recommended without additional processing and authorization by XECOM for such application.

Xecom assumes no responsibility for the use of any circuitry other than circuitry embodied in a Xecom product. No other cir-

cuits, patents, or licenses are implied.

Life Support Policy

Xecom's products are not authorized for use as Critical Components in Life Support Devices or Systems.

Life Support Devices or Systems are devices or systems which, (a) are intended for surgical implant into the body, or (b) sup-

port or sustain life, and whose failure to perform, when properly used in accordance with instructions provided in the labeling,

can be reasonably expected to result in significant injury to the user.

A Critical Component is any component of a life support device or system whose failure to perform can be reasonably ex-

pected to cause failure of the life support device or system, or to affect its safety or effectiveness.

While Xecom, Inc. has made every effort to ensure that the information presented here is accurate, Xecom will not be liable for any damages arising from errors or

omission of fact. Xecom reserves the right to modify specifications and/or prices without notice. Product mentioned herein are used for identification purposes only

and may be trademarks and/or registered trademarks of their respective companies.

Xecom Incorporated

374 Turquoise Street, Milpitas, CA 95035

Ph:408-945-6640

Fax:408-942-1346

E-Mail: Info@Cermetek.com

XECOM

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