FSK Modem and DTMF Codec
CMX865
Transmit Bell 103 FSK Mode
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
Min.
-
2222
2022
1268
1068
Typ.
300
2225
2025
1270
1070
Max.
-
2228
2028
1272
1072
Units
Baud
Hz
Hz
Hz
5
Hz
Transmit V.23 FSK Mode
Baud rate
Mark (logical 1) frequency, 1200 baud
Space (logical 0) frequency, 1200 baud
Mark (logical 1) frequency, 75 baud
Space (logical 0) frequency, 75 baud
Notes
Min.
-
1298
2097
389
449
Typ.
1200/75
1300
2100
390
Max.
-
1302
2103
391
451
Units
Baud
Hz
Hz
Hz
5
450
Hz
Transmit Bell 202 FSK Mode
Baud rate
Mark (logical 1) frequency, 1200 baud
Space (logical 0) frequency, 1200 baud
Mark (logical 1) frequency, 150 baud
Space (logical 0) frequency, 150 baud
Notes
Min.
-
1198
2197
386
486
Typ.
1200/150
1200
2200
387
Max.
-
1202
2203
388
488
Units
Baud
Hz
Hz
Hz
5
487
Hz
DTMF/Single Tone Transmit
Tone frequency accuracy
Distortion
Notes
Min.
-0.2
-
Typ.
-
1.0
Max.
+0.2
2.0
Units
%
%
6
Notes:
5. Tx signal % baud or bit rate accuracy is the same as XTAL/CLOCK % frequency
accuracy.
6. Measured between TXA and TXAN pins with Tx Level Control gain set to 0dB, 1k2Ω load
between TXA and TXAN, at VDD = 3.3V (levels are proportional to VDD - see section 4.2).
Level measurements for all modem modes are performed with random transmitted data.
0dBm = 775mVrms.
© 2005 CML Microsystems Plc
35
D/865/3
CMLMICRO [ CML MICROCIRCUITS ]
