fx469 Consumer Microcircuits Limited, fx469 Datasheet - Page 7

• Manufacturer Part Number: fx469
• Description: 1200/2400/4800 Baud Ffsk Modem
• Manufacturer: Consumer Microcircuits Limited

Specification ......
Characteristics
Notes
Fig.6 Typical Variation of Bit Error Rate with Input Level
Transmitter Output
Tx Output Level
Output Level Variation
Output Distortion
3rd Harmonic Distortion
Logic ‘1’ Carrier Frequency
Logic ‘0’ Carrier Frequency
Isochronous Distortion
1200Hz - 1800Hz/1800Hz - 1200Hz
1200Hz - 2400Hz/2400Hz - 1200Hz
2400Hz - 4800Hz/4800Hz - 2400Hz
1 x 10
1 x 10
1 x 10
1 x 10
1 x 10
1200/1800Hz or 1200/2400Hz or 2400/4800Hz
1.
2.
3.
4.
5.
6.
7.
8.
9.
10. For 1200 and 2400 baud operation only; when operating at 4800 baud the Carrier Detect output
-1
-2
-3
-4
-5
With reference to V
Xtal frequency, type and tolerance depends upon system requirements.
See Figure 5 (variation of BER with Input Signal Level).
SNR = Signal-to-Noise Ratio in the Bit-Rate Bandwidth.
See Figure 2.
Dependent upon Xtal tolerance.
10101010101 ...01 pattern.
Measured with a 150mVrms input signal (no noise); 1200/2400 baud operation.
Reference (0dB) level for C.D. probability measurements is 230mVrms.
should be ignored.
50
*
BIT RATE BANDWIDTH
2400 Baud
4800 Baud
2400 Baud
4800 Baud
DD
1200 Baud
1200 Baud
= 5.0 volts.
100
See Note
6
6
6
6
150
6
6
7
200
Min.
-
-
0
-
-
-
-
-
-
-
-
-
250
300
Typ.
25.0
20.0
1200
2400
2400
4800
775
-
1200
1800
-
3.0
2.0
INPUT SIGNAL LEVEL (mVrms)
Max.
10.0
40.0
30.0
±1.0
-
-
-
-
5.0
3.0
-
500
-
-
700
Unit
mVrms
µs
µs
20 µs
Hz
Hz
Hz
Hz
dB
%
%
Hz
Hz
800