FSK Modem and DTMF Codec
CMX865
Receive Bell 103 FSK Mode
Acceptable baud rate
Mark (logical 1) frequency, high band
Space (logical 0) frequency, high band
Mark (logical 1) frequency, low band
Space (logical 0) frequency, low band
Notes
Notes
Min.
297
2213
2013
1258
1058
Typ.
300
2225
2025
1270
1070
Max.
303
2237
2037
1282
1082
Units
Baud
Hz
Hz
Hz
Hz
Receive V.23 FSK Mode
1200 baud
Min.
Typ.
Max.
Units
Acceptable baud rate
Mark (logical 1) frequency
Space (logical 0) frequency
1188
1280
2080
1200
1300
2100
1212
1320
2120
Baud
Hz
Hz
75 baud
Acceptable baud rate
Mark (logical 1) frequency
Space (logical 0) frequency
74
382
442
75
390
450
76
398
458
Baud
Hz
Hz
Receive Bell 202 FSK Mode
1200 baud
Notes
Min.
Typ.
Max.
Units
Acceptable baud rate
Mark (logical 1) frequency
Space (logical 0) frequency
1188
1180
2180
1200
1200
2200
1212
1220
2220
Baud
Hz
Hz
150 baud
Acceptable baud rate
Mark (logical 1) frequency
Space (logical 0) frequency
148
377
477
150
387
487
152
397
497
Baud
Hz
Hz
Rx Modem Signal
Signal level
Signal to Noise Ratio (noise flat 300-3400Hz)
Notes
Min.
-45
20
Typ.
-
-
Max.
-9
-
Units
dBm
dB
8
Notes:
8. 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 4.2.
© 2005 CML Microsystems Plc
37
D/865/3
CMLMICRO [ CML MICROCIRCUITS ]
