Telephone Signalling Transceiver / Least Cost Router
CMX860
Rx Call Progress Energy Detector
Bandwidth (-3dB points) See Figure 5a
Detect threshold (‘Off’ to ‘On)
Undetect threshold (‘On’ to ‘Off’)
Hysteresis
Notes
Min.
275
-
-42.0
2.0
Typ.
-
-
-
-
Max.
665
-37.0
-
Units
Hz
dBm
dBm
dB
10,9
10,9
10,9
10,9
10,9
-
Detect (‘Off’ to ‘On’) response time
Undetect (‘On’ to ‘Off’) response time
30.0
6.0
36.0
8.0
45.0
50.0
ms
ms
Notes:
8. ‘Typical’ value refers to 2100Hz or 2225Hz signal switched between off and -33dBm.
Times measured with respect to the received line signal.
9. ‘Typical’ values refers to 400Hz signal switched between off and -33dBm
10. Rx 2-wire line signal level assuming 1dB loss in line coupling components with Rx Gain
Control block set to 0dB.
11. Thresholds and times measured with continuous binary ‘1’ for all FSK modes. Fixed
compromise line equaliser enabled. Signal switched between off and -33dBm
DTMF Decoder
Notes
Min.
Typ.
Max.
Unit
Valid input signal levels
(each tone of composite signal)
10
10
-30.0
-
0
dBm
Not decode level
(either tone of composite signal)
Twist = High Tone/Low Tone
Frequency 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 with respect to the 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
-
-
-
-
-36.0
6.0
±3.5
dBm
dB
%
-10.0
±1.8
12
12
12
-
-
-
-
-
-
-
-
-
-
-
-
-
-
0
10.0
20.0
-10.0
40.0
30.0
-
-
-
-
dB
dB
dB
dB
ms
ms
ms
ms
ms
ms
ms
12,13
14.0
40.0
-
30.0
-
25.0
-
-
Pause length ignored
15.0
Notes:
12. Referenced to DTMF tone of lower amplitude.
13 Flat Gaussian Noise in 300-3400Hz band.
Receive Input Amplifier
Notes
Min.
Typ.
Max.
Units
Input impedance (at 100Hz)
Open loop gain (at 100Hz)
Rx Gain Control Block accuracy
10.0
MW
V/V
dB
10000
-0.25
+0.25
ã 2002 Consumer Microcircuits Limited
41
D/860/5
CMLMICRO [ CML MICROCIRCUITS ]
