Call Progress Tone Detector
5
MX643 - Preliminary Information
3. External Components
N/C
1
2
3
4
16
N/C
V
DD
CLOCK
1
8
V
DD
V
DD
C3
XTAL/
CLOCK
X1
XTAL
DETECT3
ENABLE
15
V
DD
C2
C2
DETECT3
R1
C4
14
N/C
13
DETECT2
2
DETECT2
7
ENABLE
MX643P
3
6
MX643P
MX643DW
5
6
7
8
1MΩ
560pF at 3.3VDD
1.0nF at 5.0VDD
1.0µF
33pF
33pF
3.579545MHz
V
SS
12
V
SS
N/C
11
N/C
10
9
SIGIN
C1
N/C
DETECT1
4
5
SIGIN
C1
DETECT1
N/C
C1
C2
1.0nF
1.0µF
±20
±20
R1
C1
C2
C3
C4
X1
±10
±20
±20
±20
±20
refer to Sec. 6.1
For details of CLOCK frequency refer to Sec.6.1
Figure 2: Recommended External Components for Typical Applications
4. General Description
4.1 Glossary
The following glossary and Decode Truth table (found in section 5.1), describe the MX643 decoding features and
functions.
Call Progress Tones:
The single and dual frequency tones in the range of 350Hz to 620Hz specified widely for
Call Progress signaling.
Call Progress Band:
The nominal range is 340Hz to 650Hz within which the MX643 will detect Call Progress
tones. The detection algorithm requires that the tones have characteristics typical of Call Progress Tones.
Call Progress Low Band:
The nominal range is 340Hz to 490Hz. The MX643 will detect single or dual tones
falling entirely within this range, as Call Progress Low Band tones.
Call Progress High Band:
The nominal range is 600Hz to 650Hz. Single tones in this range, or dual tones
having a material frequency component within this range (e.g. 480 + 620Hz), are detected as Call Progress High
Band tones.
Special Information Tone:
The nominal range is 950Hz or 1400Hz or 1800Hz, with a tolerance of
±50Hz.
Non Call Progress Signal:
A signal falling within the nominal range (a) 200Hz to 800Hz, but NOT within the Call
Progress Band, or (b) within the nominal range 200Hz to 800Hz, but NOT meeting the DETECTION
REQUIREMENTS when the signal falls in the Call Progress Band.
Subject to the duration and other characteristics of such signals, the MX643 will usually interpret these as a Non
Call Progress Signal (e.g. speech or other signal activity).
Minimum Input Signal:
The minimum signal level for the specified tone decoding performance. The lower level
at which absence of an input signal will be registered is not specified.
No Signal:
A signal falling outside the nominal range of 120Hz to 900Hz or Special Information Tone or the
absence of an input signal. Either will be detected as a No Signal condition.
© 1996 MX•COM, INC.
Tele: 800 638 5577, 910 744 5050, Fax: 910 744 5054
Doc. #20480148.001
CMLMICRO [ CML MICROCIRCUITS ]
