Miniature Surface-Mount DAA for Audio or Data Transfer
The XE0402LCC supplies a complete telephone line
Low-profile, surface-mount package: 0.80 inches by
interface or DAA (Data Access Arrangement) in a
0.78 inches by 0.13 inches
miniature, surface-mount module. It offers an alternative
to a discrete DAA for a multitude of voice, audio, DTMF,
Meets line interface requirements for reliable V.90
fax and data communications uses. The XE0402LCC
and V.92 communications
replaces more than 25 discrete components with a single,
fully-assembled and fully-tested unit.
Typical Second Harmonic Distortion of -80 dB
The XE0402LCC does not sacrifice performance for small
size and surface-mount convenience.
Integrated 2-to-4 wire converter provides 40 dB
bandwidth, low distortion design provides sufficient
bandwidth for 56K bps analog modem communications.
Supports detection of incoming Caller ID signals
Like all Xecom DAA modules the XE0402LCC is a
Integrated Ring Detection
complete telephone interface. It includes a 2-4 wire
converter, loop current holding circuit, hook switch and
Low power operation: Just 10 millamps from a single
ring indicator. It also passes Caller ID signals. The
+ 3.3 Volt Power Supply
Solid-State Hook switch Control
for direct connection to the telephone line.
XE0402LCC BLOCK DIAGRAM
XE0402LCC Mechanical Specifications
Product Thickness at tallest component
Pin Row length from center of Pin 1 to center of Pin 8
Width of solder pad
Length of solder pad
Distance from center of last pin of pin row to product edge
Center to center distance between adjacent Pins
Distance from center of Pin 10 to center of Pin 11
Distance from center of Pin 11 to center of Pin 13
XE0402LCC PCB Layout Recommendations
Adjacent Pad Spacing center to center
Spacing center of Pin 1 to center of Pin8
Spacing center of Pin 11 to center of Pin 12
Row-to-Row Spacing Center to Center
Center of pin 12 to Center of Pin 14
Note: No Components or traces should be placed under the DAA module.
XE0402LCC Pin Configuration
XE0402LCC Pin Descriptions
Pin Name Description
+3.3 or 5 Volt power source for the XE0402LCC.
TX- is the negative half of the differential transmit data input to the XE0402LCC from the host system. If the
host system uses a single ended transmit data output, that output should be connected to TX-.
TX+ is the positive half of the differential transmit data input to the XE0402LCC from the host system. If the
host system uses a single ended transmit data output, TX+ should be grounded.
Switch-hook control to the modem. /OH is an active low input. Activating /OH closes the switch-hook causing
the XE0402LCC to seize the telephone line. The telephone line connection drops when /OH is deactivated.
The host can pulse /OH to simulate rotary dialing. The pulse rate in the US is ten pulses per second. Each digit
is dialed as a series of pulses created by closure of the hook-switch, one pulse for the digit one to ten pulses for
the digit zero. The pulses must be asymmetrical so that the hook-switch is closed for thirty-one milliseconds
and open for sixty-nine milliseconds. An inter-digit delay of at least one hundred milliseconds is required.
Ring Indicate output from the module. /RI provides a low going, Ring frequency, pulse output. The
XE0402LCC recognizes ring voltages of twenty-eight to one hundred fifty volts RMS in the frequency range of
sixteen to sixty-eight Hertz.
RX- is the negative half of the differential received data output from the XE0402LCC. If the host system uses
a single ended received data input, RX- should remain open.
RX+ is the positive half of the differential received data output from the to the host system. If the host system
uses a single ended received data input, that input should be connected to RX+.
Ground connection to the XE0402LCC. This signal provides the reference for the /OH input and /RI output.
This pin should be connected to the systems digital ground.
XE0402LCC Pin Descriptions
Pin Name Description
Ring is one half of the two-wire telephone line connection (RJ11 Pin 4). 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. Xecom recommends 0.100 inch spacing between traces connected to Ring and all other conductors
to preserve this isolation
Tip is one half of the two-wire telephone line connection (RJ11 Pin 3). The telephone company places a DC
"Battery" voltage across Tip and Ring on all public switched telephone lines. The XE0402LCC accepts this
line battery voltage without regard to its polarity.
No Connection; These pads are provided for mechanical stability only.
Typical Connections Diagram for NorthAmerica and Japan
Capacitors, C1 and C2, may be required for EMI filtering in your system. Without these
components you may experience unintended radiation when the telephone cable is attached. To
maintain required isolation C1 and C2 are high-voltage capacitors. We recommend the Novocap
ES2211N681K502NXTM. This 680 pF, 5000 volt capacitor will direct the high frequency harmonics
to the system ground.
FB1 and FB2 are ferrite beads which may be required for EMI filtering to prevent unintended
radiation when the telephone cable is attached to your system. Xecom recommends the TDK
ACB2012L-120 which provides more than 100 ohms impedance at frequencies above 100 MHz.
MOV1 protects against damage from lightening strikes on the telephone lines. Xecom recom-
mends the World Products WPSCDS-275E Thyristor to provide this protection.
F1 and F2 prevent damage to the system when a power line crosses with the telephone line.
Xecom recommends the Littlefuse 0461 1.25 for this function.
Because of its Hybrid construction, the XE0402LCC is subject to damage if overexposed 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 DAA.
220 O C
Maximum Time at 220 O C
Maximum Time above Eutectic (180 O C)
Maximum Preheat Dwell Time
Maximum Recommended Solder Temperature Profile
220 O C
180 O C
150 O C
------------------------------180 sec max-------------------------
----- 90 sec max -----
Xecom’s XE0402LCC DAA modules should be exposed to no more than one reflow cycle.
The public switched telephone network permits tone and
In the US TIA-968A sets the allowable signal level for all
rotary (pulse) dialing. The XE0402LCC supports both
signals placed on the telephone line other than live voice.
types. Tone dialing requires an external signal source to
Signal levels are measured in dBm. Zero dBm is 1 milliwatt
generate the dialing tones. The /OH line on the XE0402LCC
through a 600 ohm load. In the US the maximum magnitude is
may be pulsed to create pulse dialing.
-9 dBm. Other countries have similar regulations.
Pulse Dialing: The XE0402LCC generates dialing pulses
through momentary closures of the switch-hook. Each digit
Distortion is the most common measure of the quality of the
is represented as a series of pulses, one pulse for a one to ten
signal path provided by the DAA. The primary sources of
pulses for a zero. The pulse rate in North America is ten
this distortion is the line current holding circuit, although board
pulses per second. The dialing pulses are asymmetrical. The
layout and other factors can introduce distortion.
correct duty cycle in NorthAmerica is 31 milliseconds on and
69 milliseconds off. An inter-digit delay of at least one
Distortion varies with frequency. The voice band of the
hundred milliseconds separates the digits.
telephone line is limited to less than 4000 Hz. High speed
modems such as 33.6K bps and 56K bps require virtually all of
Tone Dialing: To permit tone dialing the XE0402LCC
this bandwidth for signal transmission. Even if the distortion
seizes the line, /OH active. For each digit a unique DTMF,
through a device is good in the center portion of the spectrum,
Dual Tone Multiple Frequency, tone pair is applied to TX+
signal quality is compromised if distortion greatly increases at
and TX-. The higher frequency tone is always larger than the
the outer limits of the voice band. The XE0402LCC provides
lower frequency one. Transmit the tones for a minimum of
a low distortion signal path across the entire voice band.
70 milliseconds, and leave a minimum of 70 milliseconds
Caller ID Reporting:
The telephone network normally sends the Caller ID signal
The following chart shows the DTMF signal frequencies for
between the first and second ring signals. The XE0402LCC
passes the Caller ID signal through to the host through the
RX+ and RX- pins. Caller ID pass-through can only be used
when the XE0402LCC is in the On-hook state, /OH high.
Power Supply Voltage
Power Supply Current
600 Ohm Impedance, 300-3400 Hz
Transmit Insertion loss
600 Ohm Impedance, 300-3400 Hz
Receive Insertion loss
600 Ohm Impedance, 3000-3400 Hz
Second Harmonic Distortion
600 Ohm Impedance, 200 to 4000 Hz
Ring Detect Sensitivity
Min. AC voltage between Tip &
Ring Type B ringer
Ring Frequencies Detected
RI Output Voltage
Ring present, Active low
No Ring signal ,Active High
VCC - .4
Voltage (active low)
Off-Hook current draw from
DC On-Hook Impedance
XE0402LCCABSOLUTE MAXIMUM RATINGS
-40 O C to +125 O C
Operating Temperature Range *
0 O C to +85 O C
* The XE0402LCC can be ordered with an Operating Temperature of -40 O C to +85 O C at extra cost.
XE0402LCC FCC Part 68 Information
When developing a product to be connected to the telephone line, it is necessary to use a circuit known as a Data
Access Arrangement (DAA) approved by the appropriate governmental agency. In the US this agency is the Federal
Communications Commission (FCC), while in Canada it is Industry Canada (IC). 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 XE0402LCC has been designed to meet all TIA-968-A requirements for hazardous voltage, line impedance and
leakage current. If the system transmits data, synthesized voice, or DTMF tones on the telephone line, the user must
certify that the signals transmitted meet basic 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:
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 XE0402LCC 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 XE0402LCC must certify that the final system meets the requirements of TIA-968-A which include the
criteria above as well as the high voltage protection provided by the XE0402LCC. This is generally accomplished
through an independent testing lab which tests the System and submits the proper paperwork. Since the XE0402LCC
already complies with FCC Part 68 rules, this should be a relatively simple process.
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 re-
garding the freedom of the described devices from patent infringement. XECOM makes no warranty of merchant-
ability 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 applica-
tions, 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 pro-
vided 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 rea-
sonably expected to cause failure of the life support device or system, or to affect its safety or effectiveness.
Copyright, Xecom © 2006
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 trade-
marks and/or registered trademarks of their respective companies.
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Web Site: http://www.xecom.com