CMX649 View Datasheet(PDF) - CML Microsystems Plc
Part Name
Description
MFG CO.
'CMX649' PDF : 50 Pages View PDF
ADM Codec
CMX649
Decoder VAD
Decay Time
Constant
(Bits 7 – 5)
Decoder VAD
Attack Time
Constant
(Bits 4 – 3)
Decoder VAD
Output Source
(Bits 2 – 1)
Reserved
(Bit 0)
Allows selection of the Voice Activity Detector decay time constant.
Bit 7
0
0
0
0
1
1
1
1
Bit 6
0
0
1
1
0
0
1
1
Bit 5
0
1
0
1
0
1
0
1
Decay Time Constant (ms),
Bit Rate in kbps
128/(Bit Rate)
256/(Bit Rate)
512/(Bit Rate)
1024/(Bit Rate)
2048/(Bit Rate)
4096/(Bit Rate)
8192/(Bit Rate)
16384/(Bit Rate)
Allows selection of the Voice Activity Detector attack time constant.
Bit 4
0
0
1
1
Bit 3
0
1
0
1
Attack Time Constant (ms)
(VAD Decay Time Constant)/4
(VAD Decay Time Constant)/8
(VAD Decay Time Constant)/16
(VAD Decay Time Constant)/32
Allows selection of the Voice Activity Detector output source.
Bit 2
0
0
1
1
Bit 1
0
1
0
1
VAD Output
Normal VAD operation.
ADM bits are driven over VAD pin at
the ADM bit rate (may be useful when
transcoding or verifying proper
application of the burst interface).
VAD output driven to 0.
VAD output driven to 1.
This bit is reserved and should be set to a logic 0.
DECODE ADM CONTROL Register ($D1)
Syllabic Time
Constant
(Bits 15 – 13)
Step size integrator Loss Coefficient: allows selection of syllabic time constant.
Bit 15
0
0
0
0
1
1
1
1
Bit 14
0
0
1
1
0
0
1
1
Bit 13
0
1
0
1
0
1
0
1
Syllabic Filter Time Constant (ms)
512/(3*Bit Rate)
768/(3*Bit Rate)
1024/(3*Bit Rate)
1536/(3*Bit Rate)
2048/(3*Bit Rate)
3072/(3*Bit Rate)
Bluetooth compatible when running at
64kbps.
4096/(3*Bit Rate)
6144/(3*Bit Rate)
© 2003 CML Microsystems Plc
27
D/649/2
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