XECOM
(1)
XE0204
XE0204
July 2000
2-Wire/4-Wire Telephone Line Interface
Description
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.
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.
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.
Features
* Small Size 0 1.5" x 1.08" 0.42"
* FCC Part 68 Compliant
* Integral Ring Detection
* Integrated Switch Hook
* Switchable between two-wire and four-wire lines
* Integral two-to-four wire convertor
* Integrated telephone line transformers
* 1500 volt isolation barrier between the telephone line
and host equipment
* 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
2 to 4 Wire
Convertor
XMIT
RCVR
Telephone
Line
Transformer
Loop
Current
Holding
Circuit
Tx Tip
Tx Ring
Hook
Switch
OH
Ring
Detect
/RI
Rx Tip
Rx Ring
4 Wire
Switch
Telephone
Line
Transformer
/4Wire
XECOM
(2)
XE0204
A
B
Denotes Pin 1
C
D
G
J
H
E
F
K
Inches
Millemeters
Dim
Min
Max
Min
Max
A
1.480
1.520
37.59
38.61
B
1.060
1.100
26.92
27.94
C
0.420
0.430
10.67
10.92
D
0.890
0.910
22.61
23.11
E
0.890
0.910
22.61
23.11
F
0.125
-
3.18
-
G
0.040
0.060
1.02
1.52
H
0.290
0.310
7.37
7.87
J
0.090
0.110
2.29
2.79
K
0.020
0.025
0.51
0.64
XE0204 Mechanical Specifications
XE0204 Pin Configuration
XE0204
(Top View)
VCC
1
20
TxTip
/RI
3
RCVR
4
17
TxRing
XMIT
5
OH
7
14
RxTip
/4Wire
8
N/C
9
Gnd
10
11
RxRing
XECOM
(3)
XE0204
XE0204 Pin Configuration
Pin
Name
Description
1
VCC
VCC supplies +5 Volts power to the XE0204
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
(4)
XE0204
Power Supply Current
4-Wire Operation
10
16
mA
Transmit Insertion loss
2-Wire line, 1000 Hz, 600 Ohm line
-0.5
0
0.5
dB
Receive Insertion Loss
2-Wire line, 1000 Hz, 600 ohm line
-0.5
0
0.5
dB
4-Wire line, 1000 Hz, 600 ohm line
0.8
3.0
dB
Telephone Line Impedance
At 1800 Hz, (2 and 4 wire Lines)
540
600
660
Ohms
Coupler Match input
Output impedance driving RCVR in four-
531
536
541
Ohms
Impedance
wire mode
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
21
dB
Ring Detect Sensitivity
Type B Ringer
38
150
Vrms
Ring Indicate Output
Ring Voltage present on Tip and Ring
0.2
0.5
Volts
Hook Switch Control Voltage
ON: (off-hook)
4.0
Volts
OFF: (on-hook)
0.8
Volts
Hook Switch Control Current
Off-Hook
0.5
mA
/4WIRE Switch
2-Wire
4.0
Volts
4-Wire
0.8
Volts
Loop Current, Tx Pair
Off-hook
0
100
mA
Loop Current, Rx Pair
4-Wire Line
0
mA
Parameter
Conditions
Min
Typ
Max Units
XE0204 Electrical Specifications
(VCC= +5V + 10%, Ta = 0C to 70C)
XE0204 Absolute Maximum Ratings
Supply Voltage - VCC
+6.5 Volts
Storage Temperature
-25
O
C to +85
O
C
Operating Temperature Range
0
O
C to +70
O
C
Maximum Lead Temperature
260
O
C
(soldering 2 seconds per wave)
XECOM
(5)
XE0204
XE0204 Typical Connection Diagram for a 2-Wire, Dial-up Line
Modem Analog
Front End
RJ11
4
3
/Ring
Receive
Transmit
OHRLY
+5 Volts
10 ohms, 1/2 W
470 pFd
2600 Volts
470 pFd
2600 Volts
FerriteBead
FerriteBead
Teccor
P3100SB
10 ohms, 1/2 W
XE0204
VCC
TxTIP
/RI
RCVR
TxRING
XMIT
OH
RxTip
/4Wire
Gnd
RxRing
XE0204 Typical Connection Diagram for a 2-Wire, Leased Line
Modem Analog
Front End
RJ11
4
3
/Ring
Receive
Transmit
OHRLY
+5 Volts
10 ohms, 1/2 W
470 pFd
2600 Volts
470 pFd
2600 Volts
FerriteBead
FerriteBead
Teccor
P3100SB
10 ohms, 1/2 W
XE0204
VCC
TxTIP
/RI
RCVR
TxRING
XMIT
OH
RxTip
/4Wire
Gnd
RxRing
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