CMX878 View Datasheet(PDF) - CML Microsystems Plc
Part Name
Description
Manufacturer
CMX878 Datasheet PDF : 61 Pages
| |||
Line Powered Modem plus DAA
CMX878
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
6
Min.
-
1198
2197
386
486
DTMF/Single Tone Transmit
Tone frequency accuracy
Distortion
Notes
7
Min.
-0.2
-
Transmit Output Level
Modem and Single Tone modes
DTMF mode, Low Group tones
DTMF: level of High Group tones wrt Low Group
Tx output buffer gain control accuracy
Notes
7
7
7
7
Min.
-11.0
-9.0
+1.0
-0.25
Typ.
1200/150
1200
2200
387
487
Typ.
-
1.0
Typ.
-10.0
-8.0
+2.0
-
Max.
-
1202
2203
388
488
Units
Baud
Hz
Hz
Hz
Hz
Max.
+0.2
2.0
Units
%
%
Max.
-9.0
-7.0
+3.0
+0.25
Units
dBm
dBm
dB
dB
Notes:
5. % carrier frequency accuracy is the same as XTAL/CLOCK % frequency accuracy.
6 Tx signal % baud or bit rate accuracy is the same as XTAL/CLOCK % frequency
accuracy.
7. Measured on a matched line with Tx Level Control gain set to 0dB, at A VDD = 3.3V
(levels are proportional to VDD). Level measurements for all modem modes are
performed with random transmitted data and without any guard tone. 0dBm =
775mVrms.
Notes:
0
-10
Bell 202
-20
-30
dBm
-40
-50
-60
-70
10
100
1000
10000
100000
Hz
Figure 14 Maximum Out of Band Tx Line Energy Limits (see note 8)
8. Measured on the line with the Tx line signal level set to -10dBm for QAM, DPSK, FSK or
single tones, -6dBm and -8dBm for DTMF tones. Excludes any distortion due to external
components.
© 2002 Consumer Microcircuits Limited
55
D/878/2
Share Link: 