CMX878 View Datasheet(PDF) - CML Microsystems Plc

Part Name

Description

Manufacturer

CMX878

Line Powered Modem plus DAA

CML Microsystems Plc 

Line Powered Modem plus DAA

CMX878

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.

90.0

5.0

Typ.

-

-

Max. Units

-

ms

72.0

-

ms

Rx Modem Energy Detector

Detect threshold (‘Off’ to ‘On)

Undetect threshold (‘On’ to ‘Off’)

Hysteresis

Detect (‘Off’ to ‘On’) response time

QAM and DPSK modes

300 and 1200 baud FSK modes

150 and 75 baud FSK modes

Undetect (‘On’ to ‘Off’) response time

QAM and DPSK modes

300 and 1200 baud FSK modes

150 and 75 baud FSK modes

Notes

10,11

10,11

10,11

Min.

-

-48.0

2.0

10,11 10.0

10,11 8.0

10,11 16.0

10,11 10.0

10,11 10.0

10,11 20.0

Typ.

-

-

-

-

-

-

-

-

-

Max.

-43.0

-

-

Units

dBm

dBm

dB

35.0 ms

30.0 ms

60.0 ms

55.0 ms

40.0 ms

80.0 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

2100Hz detector

‘Will detect’ frequency

‘Will not detect’ frequency

2225Hz detector

‘Will detect’ frequency

‘Will not detect’ frequency

Notes

10,12

10,12

10,12

10,12

Min.

-

-48.0

30.0

7.0

2050

-

2160

2335

Typ.

-

-

33.0

18.0

-

-

-

-

Max.

-43.0

-

45.0

25.0

Units

dBm

dBm

ms

ms

2160 Hz

2000 Hz

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

10,13

10,13

10,13

10,13

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

ms

Notes:

10. Gain Control block set to 0dB

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

© 2002 Consumer Microcircuits Limited

57

D/878/2

Share Link: