Low Power V.32 bis Modem
CMX869
Rx Modem Energy Detector (FSK modes)
Detect threshold (‘Off’ to ‘On)
Undetect threshold (‘On’ to ‘Off’)
Hysteresis
Notes
7, 8
7, 8
Min.
-
-48.0
2.0
Typ.
Max.
-43.0
-
-
Units
dBm
dBm
dB
-
-
-
7, 8
Detect (‘Off’ to ‘On’) response time
300 and 1200 baud FSK modes
150 and 75 baud FSK modes
7, 8
7, 8
8.0
16.0
-
-
30.0
60.0
ms
ms
Undetect (‘On’ to ‘Off’) response time
300 and 1200 baud FSK modes
150 and 75 baud FSK modes
7, 8
7, 8
10.0
20.0
-
-
40.0
80.0
ms
ms
Rx Answer Tone Detectors
Detect threshold (‘Off’ to ‘On)
Undetect threshold (‘On’ to ‘Off’)
Detect (‘Off’ to ‘On’) response time
Undetect (‘On’ to ‘Off’) response time
Notes
7,9
7,9
7,9
7,9
Min.
-
-48.0
30.0
7.0
Typ.
-
-
33.0
18.0
Max.
-43.0
-
45.0
25.0
Units
dBm
dBm
ms
ms
2100Hz detector
‘Will detect’ frequency
‘Will not detect’ frequency
2050
-
-
-
2160
2000
Hz
Hz
2225Hz detector
‘Will detect’ frequency
‘Will not detect’ frequency
2160
2335
-
-
2285
-
Hz
Hz
Rx Call Progress Energy Detector
Bandwidth (-3dB points) See Figure 6
Detect threshold (‘Off’ to ‘On)
Undetect threshold (‘On’ to ‘Off’)
Detect (‘Off’ to ‘On’) response time
Undetect (‘On’ to ‘Off’) response time
Notes
Min.
275
-
-42.0
30.0
6.0
Typ.
-
-
Max.
665
-37.0
-
45.0
50.0
Units
Hz
dBm
dBm
ms
7,10
7,10
7,10
7,10
-
36.0
8.0
ms
Notes: 7. Rx 2 or 4-wire line signal level with Rx Gain Control block set to 0dB and external components
of section 4.3 set so that level at RXAFB pin is 3.6dB below the line signal level. Measured at
AV = 3.3V.
DD
8. Thresholds and times measured with continuous binary ‘1’ for all FSK modes. Times measured
with signal switched between off and -33dBm
9. ‘Typical’ value refers to 2100Hz or 2225Hz signal switched between off and -33dBm. Times
measured wrt. received line signal.
10. ‘Typical’ values refers to 400Hz signal switched between off and -33dBm.
© 2004 CML Microsystems Plc
42
D/869/4
CMLMICRO [ CML MICROCIRCUITS ]
