ETC XE0204

XE0204
July 2000
2-Wire/4-Wire Telephone Line Interface
Description
Features
The XE0204 provides a common telephone interface
for networks integrating two and four-wire telephone
connections. The XE0204 supplies two and four wire
leased line connections, and complies with FCC Part
68 Rules for 2-wire connections to the public switched
network.
* Small Size 0 1.5” x 1.08” 0.42”
The XE0204 supports voice, data and fax transfer at
speeds to 14,400 Bits Per Second, V.32bis data transfer
over two wires and V.33 data transfer over four wires.
* Integral two-to-four wire convertor
* FCC Part 68 Compliant
* Integral Ring Detection
* Integrated Switch Hook
* Switchable between two-wire and four-wire lines
* Integrated telephone line transformers
* 1500 volt isolation barrier between the telephone line
and host equipment
The XE0204 is a complete DAA in a compact package.
It includes the telephone line transformers, loop current
holding circuit, ring detection, switch hook, two-to-four
wire convertor and four-wire switch. The small size of
the XE0204, just 1.5 square inches, allows the XE0204
to be used in most any application requiring connection
to the telephone network.
* Supports both dial-up and leased line applications
* Supports 14,400 BPS data transfer; V.32bis (2-wire),
V.33 (4-wire)
* Operates on a single +5 Volt supply
* Standard Operating Temperature Range 0C to 70C
Optional operating range, -40C to 85C available
XE0204 Block Diagram
OH
Hook
Switch
XMIT
2 to 4 Wire
Convertor
RCVR
/4Wire
Telephone
Line
Transformer
Tx Tip
Loop
Current
Holding
Circuit
Tx Ring
4 Wire
Switch
Ring
Detect
/RI
Rx Tip
Telephone
Line
Transformer
XECOM
(1)
Rx Ring
XE0204
XE0204 Mechanical Specifications
Dim
A
B
C
D
E
F
G
H
J
K
Inches
Min
Max
1.480
1.520
1.060
1.100
0.420
0.430
0.890
0.910
0.890
0.910
0.125
0.040
0.060
0.290
0.310
0.090
0.110
0.020
0.025
Millemeters
Min
Max
37.59 38.61
26.92 27.94
10.67 10.92
22.61 23.11
22.61 23.11
3.18
1.02
1.52
7.37
7.87
2.29
2.79
0.51
0.64
A
B
Denotes Pin 1
C
D
G
K
J
H
E
F
XE0204 Pin Configuration
XE0204
(Top View)
XECOM
VCC
1
20
TxTip
/RI
RCVR
XMIT
3
4
5
17
TxRing
OH
/4Wire
N/C
Gnd
7
8
9
10
14
RxTip
11
RxRing
(2)
XE0204
XE0204 Pin Configuration
Pin
Name
1
VCC
3
/RI
Ring Indicate, output, active low, TTL. /RI indicates the XE0204 is receiving a ring signal. /RI remains
low for the duration of each ring.
4
RCVR
RCVR acts as the analog output for signals recevied from the telephone line by the XE0204. In two wire
mode the received signal is placed on RCVR by the 2-to-4 wire convertor. In four wire mode the
received signal comes directly from the receive phone line pair.
5
XMIT
XMIT provides the analog input to the XE0204 for signals to be transmitted onto the telephone line. In
two wire mode the signal is passed to the 2-to-4 wire convertor. In four wire mode the signal goes
directly the transmit phone line pair.
7
OH
Hookswitch relay control. A high on OH closes the internal relay and connects the equipment to the
telephone line. OH must be forced high to maintain a 2 wire or 4 wire leased line.
8
/4Wire
/4Wire is an active low input to the XE0204 which selects four wire operation. If pin 8 is open or driven
high, two wire mode is selected.
9
N/C
No Connection
10
Gnd
Gnd provides the ground reference connection to the XE0204.
11
RxRing
RxRing provides the Ring connection to the receive pair of the four wire phone line. RxRing is not used
for two wire connections. RxRing has 1500 volts isolation from the rest of the circuitry. This isolation
must be preserved throughout the system.
14
RxTip
RxTip provides the Tip Connection to the receive pair of the four wire phone line. RxTip is not used for
two wire connections. TxTip has 1500 volts isolation from the rest of the circuitry. This isolation must
be preserved throughout the system.
17
TxRing
TxRing provides the Ring Connection to two wire lines as well as to the transmit pair of four wire phone
lines. TxRing has 1500 volts isolation from the rest of the circuitry. This isolation must be preserved
throughout the system.
20
TxTip
TxTip provides the Tip Connection to two wire lines as well as to the transmit pair of four wire phone
lines. TxTip has 1500 volts isolation from the rest of the circuitry. This isolation must be preserved
throughout the system.
XECOM
Description
VCC supplies +5 Volts power to the XE0204
(3)
XE0204
XE0204 Electrical Specifications
Parameter
(VCC= +5V + 10%, Ta = 0C to 70C)
Conditions
Min
Power Supply Current
4-Wire Operation
Transmit Insertion loss
2-Wire line, 1000 Hz, 600 Ohm line
Receive Insertion Loss
Typ
Max Units
10
16
mA
-0.5
0
0.5
dB
2-Wire line, 1000 Hz, 600 ohm line
4-Wire line, 1000 Hz, 600 ohm line
-0.5
0
0.8
0.5
3.0
dB
dB
Telephone Line Impedance
At 1800 Hz, (2 and 4 wire Lines)
540
600
660
Ohms
Coupler Match input
Impedance
Output impedance driving RCVR in fourwire mode
531
536
541
Ohms
Transmit Input Impedance
At 1800 Hz
8
10
12
KOhms
Receive Output Impedance
2 Wire mode, 1800 Hz
10
100
Ohms
Transhybrid Loss
2-wire mode, 1 KHz, 600 ohm line
15
Ring Detect Sensitivity
Type B Ringer
38
Ring Indicate Output
Ring Voltage present on Tip and Ring
Hook Switch Control Voltage
ON: (off-hook)
OFF: (on-hook)
4.0
Hook Switch Control Current
Off-Hook
0.5
/4WIRE Switch
2-Wire
4-Wire
4.0
Loop Current, Tx Pair
Off-hook
Loop Current, Rx Pair
4-Wire Line
21
0.2
0
dB
150
Vrms
0.5
Volts
0.8
Volts
Volts
mA
0.8
Volts
Volts
100
mA
0
mA
XE0204 Absolute Maximum Ratings
XECOM
Supply Voltage - VCC
+6.5 Volts
Storage Temperature
-25 C to +85 C
Operating Temperature Range
0 C to +70 C
Maximum Lead Temperature
(soldering 2 seconds per wave)
260 C
O
O
O
O
O
(4)
XE0204
XE0204 Typical Connection Diagram for a 2-Wire, Dial-up Line
+5 Volts
XE0204
Modem Analog
Front End
10 ohms, 1/2 W
VCC
TxTIP
Teccor
P3100SB
/RI
/Ring
Receive
RCVR
Transmit
XMIT
OHRLY
OH
TxRING
10 ohms, 1/2 W
FerriteBead
4
3
FerriteBead
470 pFd
2600 Volts
RxTip
RJ11
470 pFd
2600 Volts
/4Wire
Gnd
RxRing
XE0204 Typical Connection Diagram for a 2-Wire, Leased Line
+5 Volts
XE0204
Modem Analog
Front End
/Ring
10 ohms, 1/2 W
VCC
TxTIP
Teccor
P3100SB
/RI
Receive
RCVR
Transmit
XMIT
OHRLY
OH
TxRING
10 ohms, 1/2 W
RxTip
FerriteBead
RJ11
4
3
FerriteBead
470 pFd
2600 Volts
470 pFd
2600 Volts
/4Wire
Gnd
XECOM
RxRing
(5)
XE0204
XE0204 Typical Connection Diagram for a 4-Wire, Leased Line
+5 Volts
XE0204
Modem Analog
Front End
/Ring
10 ohms, 1/2 W
VCC
TxTIP
/RI
Receive
RCVR
Transmit
XMIT
FerriteBead
10 ohms, 1/2 W
Teccor
P3100SB
TxRING
OH
RJ11
FerriteBead
4
3
RxTip
/4Wire
Gnd
4
3
FerriteBead
10 ohms, 1/2 W
OHRLY
RJ11
Teccor
P3100SB
RxRing
10 ohms, 1/2 W
FerriteBead
470 pFd
2600 Volts
Recommended Parts
XECOM
Reference Designation
Recommended Part Number
Ferrite Beads
TDK ACB2012L-120-X
High Voltage Capacitors
Panasonic ECKDRS471, 470 pfd, 2600 Volts
RJ11 Telephone Jack
Stewart SS6446NF
(6)
XE0204
XE0204 FCC Instructions
When developing a product to be connected to the telephone line, it is necessary to use a circuit described as a Data Access
Arrangement (DAA) which is approved by the appropriate governmental agency. In the US, for example, this agency is the Federal
Communications Commission (FCC), while in Canada it is the Department of Communications (DOC). These agencies test and
approve the product to ensure that it meets their specifications, thereby protecting the telephone system from damage and
protecting the user from high voltage transients (such as lightning strikes) which may come down the telephone line.
The XE0204 has been designed to meet all FCC Part 68 requirements for hazardous voltage, surge protection and leakage current.
If the system developed transmits data, or DTMF tones on the telephone line, the user must certify that the signals transmitted meet
basic FCC requirements for maximum transmission levels, out of band energy and billing delay. Full details may be obtained from
the FCC under Part 68 of the FCC Rules and Regulations, or in Title 47 of the Code of Federal Regulations, however the basic
requirements are as follows:
1. Maximum Transmit Level
For the normal “permissive” (standard) telephone line, equipment which transmits data (such as a modem) must not exceed a
transmission level of -9 dBm.
2. Out of Band Energy
Data equipment must not transmit “out of band” energy on the telephone line which exceeds the following limits:
Frequency
200Hz
to
Range
3990Hz
Max. Power
-9 dBm
3990Hz
4005Hz
8kHz
to
to
to
4005Hz
16kHz
94kHz
-27 dBm
-16 dBm
-47 dBm
86kHz
270kHz
to
to
270kHz
6MHz
-46 dBm
-6 dBm
3. DTMF Transmission Level
If the system is capable of DTMF dialing, the maximum DTMF transmission level must be less than 0 dBm averaged over a 3
second interval.
4. Billing Delay
A delay of 2 seconds or greater is required after the time the XE0204 is taken “off hook” and before any information is transmitted.
This is required to ensure that billing information may be exchanged between telephone company central offices without
interference.
The user of the XE0204 must certify to the FCC that the final system meets the requirements of Part 68 which include the criteria
above as well as the high voltage protection provided by the XE0204. This is generally accomplished through an independent
testing lab which tesst the System and submits the proper paperwork to the FCC for approval. Since the X0204 already complies
with FCC Part 68 rules, this is a relatively simple process.
XECOM
(7)
XE0204
Terms of Sale
Devices sold by XECOM are covered by the warranty provisions appearing in its Terms of Sale only. XECOM
makes no warranty, 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 environmental 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 circuits, 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) support 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 expected to cause failure of the life support device or system, or to affect its safety or effectiveness.
Copyright, Xecom © 2000
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
Email: [email protected]
XECOM
(8)
XE0204