CMX878 View Datasheet(PDF) - CML Microsystems Plc
Part Name
Description
MFG CO.
'CMX878' PDF : 63 Pages View PDF
Line Powered Modem plus DAA
CMX878
DTMF Decoder
Valid input signal levels
(each tone of composite signal)
Not decode level
(either tone of composite signal)
Twist = High Tone/Low Tone
Frequency Detect Bandwidth
Frequency Not Detect Bandwidth
Max level of low frequency noise (i.e. dial tone)
Interfering signal frequency <= 550Hz
Interfering signal frequency <= 450Hz
Interfering signal frequency <= 200Hz
Max. noise level wrt. signal
DTMF detect response time
DTMF de-response time
Status Register b5 high time
‘Will Detect’ DTMF signal duration
‘Will Not Detect’ DTMF signal duration
Pause length detected
Pause length ignored
Notes Min.
10
10
14
14
14
14,15
-30.0
-
-10.0
±1.8
-
-
-
-
-
-
-
14.0
40.0
-
30.0
-
Notes:
14. Referenced to DTMF tone of lower amplitude.
15 Flat Gaussian Noise in 300-3400Hz band.
Typ.
-
-
-
-
-
-
-
-
-
-
-
-
-
25.0
-
-
Max. Unit
0.0
-36.0
6.0
-
±3.5
0.0
10.0
20.0
-10.0
40.0
30.0
-
-
-
-
15.0
dBm
dBm
dB
%
%
dB
dB
dB
dB
ms
ms
ms
ms
ms
ms
ms
Receive Input Amplifier
Input impedance (at 100Hz)
Open loop gain (at 100Hz)
Rx Gain Control Block accuracy
Notes Min.
10.0
-0.25
Typ.
10000
Max.
+0.25
Units
Moh
m
V/V
dB
© 2002 Consumer Microcircuits Limited
58
D/878/2
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