CMX865D2 CML Microcircuits, CMX865D2 Datasheet - Page 39

• Manufacturer Part Number: CMX865D2
• Description: FSK Modem and DTMF Codec
• Manufacturer: CML Microcircuits

FSK Modem and DTMF Codec
Notes:
© 2005 CML Microsystems Plc
DTMF Decoder
Valid input signal levels
(each tone of composite signal)
Not decode level
(either tone of composite signal)
Twist = High Tone/Low Tone
Frequency Detect Bandwidth
Frequency Not Detect Bandwidth
Max level of low frequency noise (i.e. dial tone)
Max. noise level wrt. signal
DTMF detect response time
DTMF de-response time
Status Register b5 high time
‘Will Detect’ DTMF signal duration
‘Will Not Detect’ DTMF signal duration
Pause length detected
Pause length ignored
Falsing performance
Receive Input Amplifier
Input impedance (at 100Hz)
Open loop gain (at 100Hz)
Rx Gain Control Block accuracy
Interfering signal frequency <= 550Hz
Interfering signal frequency <= 450Hz
Interfering signal frequency <= 200Hz
12. Referenced to DTMF tone of lower amplitude.
13. Flat Gaussian Noise in 300-3400Hz band.
14. Mitel CM7291 test tape, 1kHz reference tone set to 775mVrms.
39
Notes
12, 13
Notes
12
12
12
14
8
8
-0.25
10.0
-31.0
-10.0
Min.
Min.
±2.2
14.0
40.0
30.0
–
-
-
-
-
-
-
-
-
-
-
10000
Typ.
25.0
Typ.
13
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-38.0
-10.0
Max.
10.0
±3.5
10.0
20.0
40.0
30.0
15.0
+0.25
2.0
0.0
Max.
–
-
-
-
-
-
30mins
CMX865
falses/
Units
D/865/3
dBm
dBm
Moh
Unit
V/V
ms
ms
ms
ms
ms
ms
ms
dB
dB
dB
dB
dB
dB
%
%
m