Low Power V.22 bis Modem
CMX868
Rx Modem S1 Pattern Detector
(DPSK and QAM modes)
Will detect S1 pattern lasting for
Will not detect S1 pattern lasting for
Hold time (minimum detector ‘On’ time)
Notes
Min.
Typ.
Max.
Units
ms
90.0
–
5.0
–
–
–
–
72.0
–
ms
Rx Modem Energy Detector
Detect threshold (‘Off’ to ‘On)
Undetect threshold (‘On’ to ‘Off’)
Hysteresis
Notes
10,11
10,11
10,11
Min.
–
-48.0
2.0
Typ.
Max.
-43.0
–
Units
dBm
dBm
dB
–
–
–
–
Detect (‘Off’ to ‘On’) response time
QAM and DPSK modes
300 and 1200 baud FSK modes
150 and 75 baud FSK modes
10,11
10,11
10,11
10.0
8.0
16.0
–
–
–
35.0
30.0
60.0
ms
ms
ms
Undetect (‘On’ to ‘Off’) response time
QAM and DPSK modes
300 and 1200 baud FSK modes
150 and 75 baud FSK modes
10,11
10,11
10,11
10.0
10.0
20.0
–
–
–
55.0
40.0
80.0
ms
ms
ms
Rx Answer Tone Detectors
Detect threshold (‘Off’ to ‘On)
Undetect threshold (‘On’ to ‘Off’)
Hysteresis
Detect (‘Off’ to ‘On’) response time
Undetect (‘On’ to ‘Off’) response time
Notes
10,12
10,12
10,12
10,12
10,12
Min.
–
-48.0
2.0
30.0
7.0
Typ.
–
–
–
33.0
18.0
Max.
-43.0
–
–
45.0
25.0
Units
dBm
dBm
dB
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 7a
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.
–
–
–
36.0
8.0
Max.
665
-37.0
–
45.0
50.0
Units
Hz
dBm
dBm
ms
10,13
10,13
10,13
10,13
ms
Notes:
10. Rx 2 or 4-wire line signal level assuming 1dB loss in line coupling transformer with Rx
Gain Control block set to 0dB and external components as section 1.4.2.
11.Thresholds and times measured with random data for QAM and DPSK modes, continuous
binary ‘1’ for all FSK modes. Fixed compromise line equaliser enabled. Signal switched
between off and -33dBm
12. ‘Typical’ value refers to 2100Hz or 2225Hz signal switched between off and -33dBm.
Times measured wrt. received line signal
13. ‘Typical’ values refers to 400Hz signal switched between off and -33dBm
ã 2004 CML Microsystems Plc
44
D/868/9
CMLMICRO [ CML MICROCIRCUITS ]
