XE056LCC-1 Cermetek Microelectronics, XE056LCC-1 Datasheet - Page 7

• Manufacturer Part Number: XE056LCC-1
• Manufacturer: Cermetek Microelectronics

Specifications of XE056LCC-1

• Lead Free Status / Rohs Status: Supplier Unconfirmed

Dialing:
The XE056LCC supports both tone and rotary
(pulse) dialing. Tone dialing requires an external
signal source to generate the dialing tones. Rotary
dialing is accomplished by pulsing the /OH line.
Pulse Dialing: Dialing pulses are created by
momentarily closing the switch-hook. Each digit
is represented as a series of pulses; one pulse for
the digit one, two pulses for a two, up to ten
pulses for a zero. The pulse rate is ten pulses per
second. These dialing pulses are asymmetrical.
For the correct duty cycle consult with the local
country regulations. An inter-digit delay of at least
one hundred milliseconds separates the digits.
Tone Dialing: To permit tone dialing the /OH line
msut be activated to seize the line. Dialing tones
can then be presented on T1 and T2. Each digit
consists of a unique DTMF, Dual Tone Multiple
Frequency, tone pair. Transmit teh tones for a
minimum of 70 milliseconds with a minimum of
70 milliseconds between digits.
Below is a list of the DTMF signal frequencies.
XE056LCC Applications Notes
Digit
Cermetek
1
2
3
4
5
6
7
8
9
0
*
#
Lower Tone
697
697
697
770
770
770
852
852
852
941
941
941
Upper Tone
1209
1336
1477
1209
1336
1477
1209
1336
1477
1336
1209
1477
(7)
Signal Levels:
FCC Part 68 Rules set the maximum level of all
signals on the telephone line other than live voice.
Signal levels are measured in dBm; 0 dBm is 1
milliwatt through a 600 ohm load. Dialing tones
may have a combined signal level of up to 0 dBm;
all other signals are limited to a maximum of -9
dBm.
Insertion Loss: There is some loss of signal
strength as the signal passes through the DAA.
This "insertion" loss should be considered when
placing signals across T1 and T2 for transmission.
The typical insertion loss of the XE056LCC is 6
dB.
Total Harmonic Distortion:
Total harmonic distortion measures the quality of
the DAA signal path quality. The primary sources
of distortion are the telephone line transformer and
the line current holding circuit, although board
layout and other factors can introduce distortion.
Total harmonic distortion varies with frequency.
The telephone line provides a frequency band of
100 to 4000 Hz. High speed modems using V.90
and V.92 protocols require virtually all of this
bandwidth. Even if the total harmonic distortion is
very good in the center of the spectrum, distortion
elsewhere will adversely affect data transmission.
XE056LCC