PMR Signalling Processor
CMX881
AC Parameters (cont.)
Notes
Min.
Typ.
2.0
Max.
Unit
CTCSS Encoder
Frequency Range
60.0
-1.0
260
±0.3
+1.0
4.0
Hz
%
Tone Frequency Accuracy
Tone Amplitude Tolerance
Total Harmonic Distortion
61
62
dB
%
Selcall Encoder
Frequency Range
400
-1.0
3000
±0.3
+1.0
4.0
Hz
%
Tone Frequency Accuracy
Tone Amplitude Tolerance
Total Harmonic Distortion
63
62
dB
%
2.0
DTMF Encoder
Output signal level
High tone
0
-2
0
dB
dB
dB
%
Low tone (twist on)
(twist off)
64
64
Output distortion
2
5
DCS Encoder
Bit Rate
134.4
775
bits/s
dB
Amplitude Tolerance
61
-1.0
-1.0
+1.0
FFSK/MSK Encoder
Output signal level
Output level variation
Output distortion
mVrms
dB
+1.0
5
%
3rd harmonic distortion
3
%
Logic 1 freq
Logic 0 freq
1200baud and 2400baud
1200baud
1198
1798
2398
1200
1800
2400
1202
1802
2402
40
Hz
Hz
2400baud
Hz
Isochronous distortion (0 to 1 and 1 to 0)
µs
61
62
63
64
VDD(A) = 3.0V and TX Sub-Audio Level set to 88mV p-p (31mV rms).
Measured at MOD_1 or MOD_2 output.
Notes:
VDD(A) = 3.0V and Tx Audio Level set to 871mV p-p (308mV rms).
With respect to high tone level
2004 CML Microsystems Plc
54
D/881/7
CMLMICRO [ CML MICROCIRCUITS ]
