Cermetek DataSheet for product XE2420G

XE2420G

September 2003

Smallest World-Wide 2400 BPS Modem

Description

Features

Xecom’s XE2420G offers unprecedented design

* Small Size: The HyPLCC™ measures less than 1 inch

flexibility. It provides a global common communications

by 1 inch square and 0.350 inches thick

solution in the smallest available package. The

* Surface-mountable: The HyPLCC™ package is

XE2420G fits a standard 68-Pin PLCC socket and can be

equivalent to a 68-Pin PLCC device.

socketed or soldered onto the board in an automated

* Data transfer from 300 to 2400 BPS using V.22bis,

assembly process. The XE2420G allows incorporation of

V.22,V.23,V.21,Bell212A,andBell103Protocols

a dial-up access where no other modem will fit.

* Modem Control and Configuration via industry

standard AT Commands.

The surface mount package and small size of the

XE2420G are particularly impressive because it is a

* Supports V.42 and MNP error correction;

complete modem. The DAA, RAM, Crystal; everything

* Complete integrated solid-state DAA includes, Ring

is included. Like all Xecom modems, the XE2420G

Detect, Loop Current Holding Circuit, Hook Switch

and Metallic Surge Protection;

includes transferrable FCC Part 68 Registration.

* User Transferrable FCC Part 68 Registration

No 2400 BPS modem incorporates more features than

* Complies with telephone networks around the world.

the XE2420G. The XE2420G is one of the few low-speed

* UL60950Recognition

modems available with built-in error correction . The

XE2420G incorporates both a sleep mode and power

* Handset Interrupt detects parallel telephone pick -up

down mode making it ideal for battery powered

* Low Power operation, typically less than 100 mW,

applications. The XE2420G also incorporates Handset

includes automatic sleep mode and power down

operation;

Interrupt to prevent conflicts in shared line applications.

XE2420G BLOCK DIAGRAM

/Reset

/TXD

/RXD

/RTS

/DSR

Modem

Global

/DCD

Controller

Analog

Telephone

Tip

/CTS

Front

Line

Ring

/DTR

End

Interface

/RI

/INT

(DAA)

SPKR

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XE2420G

XE2420G Mechanical Specifications

(TOP)

.050”

45 O

Inches

Millimeters

Dimension

Min

Typ

Max

Min

Typ

Max

0.345

0.350

0.355

8.76

8.89

9.02

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

0.195

0.200

0.205

10.03

10.16

10.29

i(radius)

0.015

0.020

0.025

0.13

0.25

0.38

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XE2420G

XE2420G Pin Configuration

/DCD

/CTS

/RESET

/DSR

RING

/RTS

N/C

/DTR

TIP

/RXD

N/C

/TXD

Top

/RI

GND

SPKR

N/C

/INT

VCC

N/C

Pin Descriptions

PIN NAME

DESCRIPTION

/DCD

/DCD is an active low output from the modem. /DCD indicates the presence of a valid carrier

signal.

/CTS

/CTS is an active low output from the modem. When hardware flow control is active, the modem

asserts /CTS to indicate that it can accept data from the terminal equipment on /TXD.

/RESET

/RESET is an active low input which initiates 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 active low output from the modem. /DSR is forced active.

/RTS

/RTS is an active low input to the modem. When hardware flow control is active, /RTS indicates

to the modem that the host has data to send.

/DTR

/DTR is an active low input to the modem. The operation of /DTR is controlled by bit 15 of

communicate. If /DTR is removed while the modem is on-line it will exit data mode and enter

command mode.

/RXD

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

the host terminal equipment.

/TXD

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

terminal equipment to the modem.

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XE2420G

XE2420G Pin Descriptions (continued)

PIN NAME

DESCRIPTION

/RI

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

Tip and Ring, the /RI output goes low and toggles with the cadence of the ring signal.

Ground

Ground provides the reference voltage for all host interface signals.

SPKR

SPKR allows connection of a speaker to monitor modem operations. SPKR cannot directly drive

a speaker. An amplifier with a minimum input impedance of 300 ohms is required. The signal on

SPKR is controlled by theATM command.

N/C

No internal connection

/INT

/INT provides an active low hardware interrupt signal from the XE2420G. The operation of this

interrupt pin is programmable using the modem’s register U70.

VCC

VCC provides 3.3 volt power to the modem.

N/C

No internal connection

16-19

No Pin

20-21

N/C

No internal connection

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 XE2420G 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 XE2420G 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

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XE2420G

XE2420G Soldering Instructions

The XE2420G 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 XE2420G must not be exposed to direct Infrared (IR) heating. If your process includes direct IR heating, you

must shield the XE2420G from the infrared rays.

MaximumTemperature

220 O C

Maximum Time at 220 O C

20 Seconds

Maximum Time above Eutectic (180 O C)

90 Seconds

Maximum Preheat Dwell Time

180 Seconds

Maximum Recommended Solder Temperature Profile

220 O C

180 O C

150 O C

180 sec. max .

20 sec. max.

90 sec. max.

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XE2420G

XE2420G Electrical Specifications

Parameter

Min

Typ

Max

Units

Comments

VCC

3.0

3.3

3.6

Volts

ICC

On Line

ICC (Sleep Mode)

ICC (Power down Mode)

U65=2000h

Ring Voltage Detected

150

VRMS

Type B Ringer

Ring Frequency Detected

15.3

Type B Ringer

Telephone Loop Current

100

Line Impedance

600

Ohms

Data Transmit level

-12.0

-9.0

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

XE2420G 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

PreheatDwellTime

120 to 180 seconds

1 The XE2420G can be ordered with an Operating Temperature of -40 O C to +85 O C at extra cost. Order XE2420G-ITR

or to specify Industrial Temperature Range (ITR).

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XE2420G

XE2420G Typical Connection Diagram

To Host Serial Port

XE2420G

( 1) /DCD

(2) /CTS

RJ11

(3) /Reset

(4) /DSR

RING (24)

(5) /RTS

N/C (23)

(6) /DTR

TIP (22)

(7) /RXD

N/C (21)

(8) /TXD

N/C (20)

(9) /RI

NP (19)

(10) GND

NP (18)

(11) SPKR

NP (17)

(12) /INT

NP (16)

VCC

(13) N/C

(14) VCC

(15) N/C

Parts List for XE2420G Typical Connection Diagram

Reference

Designation

Qty

Description

C1,C2

Cap.470pfd2600V,PanasonicECKDRS471

PTC,RaychemTR600-150

Notes:

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.

2. If additional componants, such as ferrite beads, are connected in series with Tip and Ring to provide additional

EMA filtering, Xecom recommends adding surge protection in front of those compannats to protect them from

dmage due to lightning strikes. Xecom recommends the Teccor Sidactor to provide this type of suplemental

protection.

3. The XE2420G includes internal circuitry to protect the modem from damage due to lightning strikes. However,

any components placed on the Tip and Ring traces will not be protected. If you add any components between

the phone jack and Modem Module, a surge protector such as the Teccor P3100BA Sidactor should be placed

before these components to protect them from lightning damage.

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XE2420G

Application Note: Using a 68-Pin PLCC Socket

The XE2420G can be inserted into a socket for a 68-pin PLCC device. The HyPLCC package uses only 20 pins; 15

on one side and 5 on the opposite side. Alignment within the socket is critical for all pins of the XE2420G to make

contact with the appropriate pins of the PLCC socket. The drawing below illustrates how the XE2420G fits into the

68-pin PLCC socket. Emulation Technology’s S-SMT-17-068-A socket is representative of sockets that can be used

withtheXE2420G.

XE2420G

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XE2420G

XE2420G Special Features

The XE2420G includes special features which will be

Upon detection of the interrupt the application host can

highly valuable for some applications. These features

read User Register U70 to determine teh source of the

include Error Correction, Power Down Mode, Handset

interrupt. Bit 2 of that register indicates that a parallel

Interrupt, and Caller ID Decoding.

handset has been detected. The application host can

then intiate a disconnect to permit the handset to be

ErrorCorrection:

used.

TheXE2420GincorporatesV.42errorcorrection.V.42error

The Handset Interrupt feature prevents equipment,

correction incoprorates two error Correction Schemes,

which shares the telephone line with a standard handset,

LAPM and MNP. Either of these portocols can correct

such as a residential electrical meter, from blocking

99% of the errors which could occur in the data stream

emergency calls.

during normal transmission due to noise and line hits on

teh telephone line. Error correction is controlled with the

CallerIDDecoding:

AT/N command.

The XE2420G can detect and pass Caller ID information

PowerDownMode:

to the local system host. Detection of the Caller ID

information allows the application to answer calls from

The primary circuits of the XE2420G can be shut down

only known sources. When a Caller ID signal is received,

by a single command from the host, reducing power

the XE2420G provides the “CIDM” response to the host

consumption to less than 50 microamps. This makes the

to acknowledge that Caller ID information is being

XE2420G ideal for battery powered applications. Issuing

detected. The modem’s Interrupt Register, U70, can also

the AT:U65,20E0<CR> command shuts down the

be set to create an interrupt when Caller ID is detected.

XE2420G’s modem controller and analog front end.The

XE2420G can be restored to normal operation by

TheXE2420GdecodesandpassestheCallerIDcharacters

activating the modem’s RESET signal on Pin 3. The

to the application host as they are received and provides

XE2420G will be fully awakenend a minimum of 300

the “NO CARRIER” response to indicate when the Caller

milliseconds after RESET is applied.

ID message is complete. The XE2420G now resumes

monitoringtheincomingRingsignal. Ifthecallingnumber

HandsetInterrupt:

is recognized by the application host, it can initiate a

connection using the ATA command.

The XE2420G constantly monitors the telephone line’s

DC loop voltage and current. When a change is detected

in the electrical characteristcs of the telephone line, the

XE2420G activates the /INT output, Pin 13.

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XE2420G

XE2420G AT Commands

The XE2420G uses "AT" commands for modem control

Command Buffer - The Command Buffer holds a

and configuration.

This section describes the AT

maximum of 48 characters, including theAT prefix. If the

command format and lists the AT commands, Registers

command buffer overflows, the modem issues an

and Result codes.

"ERROR" result code and commands are not executed.

Data Mode: The XE2420G enters data mode after

Command Line Editing - The backspace edits a

establishing a remote modem connection and issuing

command line before it is executed. The backspace key,

the appropriate result code. In the Data Mode the

(Control and H simultaneously on some systems),

modem sends all data presented on Transmit Data (/

erases the previous character in the command line.

TXD) to the remote modem and puts data from the

remote modem onto Received Data (/RXD). When the

than a backspace to edit the command line.

modem exits data mode, it issues a "NO CARRIER"

result code.

Re-Execute Last Command - TheA/ command causes

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

Command Mode: The XE2420G enters command mode

the only command which does not require the "AT"

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

prefix.

escape code. In command mode the modem accepts

commands from the host on transmit data. Appropriate

Omitted Parameters - Most commands include a

result codes are returned on received data.

parameter which determines how the functions will be

set. When the command parameter is omitted from the

CommandLineFormat

command string, it is assumed to be a 0.

Command lines issued to the modem follow a strict

format. Each command begins with the prefix AT. The

Escape Characters -A 3 character escape sequence may

command buffer stores the command line and executes it

be entered to switch the modem into command mode

upon receipt of a carriage return. Until executed, the

while on line. The escape character, set by Register S2,

command line can be edited with the backspace key.

must be entered 3 times in succession to execute the

escape.An AT command must then be entered within the

Command Prefix - Each command, except the A/

period defined by S12 to enter command mode. The

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

default escape sequence is "+++."

may be both upper case or both lower case but cannot be

of different cases. The prefix identifies the speed and

Result Codes - The modem issues a result code after

parity of the commands sent to the modem. The modem

each action. Result codes may be sent as full words, one

determines data rate by measuring the width of the

or two digit numeric codes, or may be disabled all

incoming bits. Parity is determined by comparing the

together. Each result code ends with a carriage return

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

when numeric result codes are chosen. When full word

result codes are chosen, a Line Feed and Carriage Return

Command Line - Commands may be