Low Power V.22 Modem
CMX867
The level detectors include hysteresis. The threshold levels - measured at the 2 or 4-wire line with unity
gain filters, using the line interface circuits described in section 1.4.2, 1.0 dB line coupling transformer
loss and with the Rx Gain Control block set to 0dB - are nominally:
‘Off’ to ‘On’
‘On’ to ‘Off’
-44.5dBm
-47.0dBm
Note that if any changes are made to the programmed values while the CMX867 is running in
Programmed Tone Detect mode they will not take effect until the CMX867 is next switched into
Programmed Tone Detect mode.
On powerup or after a reset, the programmable tone pair detector is set to act as a simple 2130Hz +
2750Hz detector.
© 2004 Consumer Microcircuits Limited
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