XECOM XE0204 Datasheet

2-Wire/4-Wire Telephone Line Interface

XE0204

July 2000

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

OH

XMIT

RCVR

/4Wire

4 Wire
Switch

2 to 4 Wire

Convertor

Telephone

Line

Transformer

Loop
Current
Holding

Circuit

/RI

Telephone

Line

Transformer

XECOM (1) XE0204

Hook

Switch

Tx Tip

Tx Ring

Ring

Detect

Rx Tip

Rx Ring

XE0204 Mechanical Specifications

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

A

B

Denotes Pin 1

D

XE0204 Pin Configuration

VCC 1 20 TxTip

RCVR 4 17 TxRing

XMIT 5

OH 7 14 RxTip

/4Wire 8

N/C 9
Gnd 10 11 RxRing

C

G J

H

XE0204

(Top View)

/RI 3

K

F

E

XECOM (2) 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 (3) XE0204