CMX649 View Datasheet(PDF) - CML Microsystems Plc
Part Name
Description
MFG CO.
'CMX649' PDF : 50 Pages View PDF
ADM Codec
CMX649
7.1.3 Operating Characteristics
The following conditions are assumed unless otherwise specified: VDD = 2.7V to 5.5V at TAMB = -40 to
+85°C, Audio Test Frequency = 820Hz, Xtal/Clock f0 = 4.096MHz, Data Rate = 32kbps, Audio reference
level (0 dBm0) = 489mVRMS.
DC Parameters
IDD (powersaved) at VDD = 3.0V
IDD (powersaved) at VDD = 5.0V
IDD (XTAL only) at VDD = 3.0V
IDD (XTAL only) at VDD = 5.0V
IDD (low powermode) at VDD = 3.0V
IDD (low powermode) at VDD = 5.0V
Notes
1
1
1
1
1
1
Min.
–
–
-
-
–
–
Typ.
1.0
1.0
0.34
0.91
2.0
3.4
Max.
10.0
10.0
2.0
2.5
3.8
4.9
Units
µA
µA
mA
mA
mA
mA
Input logic 1
Input logic 0
Output logic 1
Output logic 0
Logic I/O Pin Input Impedance
Logic Input Pins, Pull-up Resistor
Digital Output Impedance
Analog Input Impedance
Analog Output Impedance
Three State Output Leakage
DAC Full Scale Reference Voltage
70%VDD
–
80% VDD
–
1.0
300
–
–
–
–
–
–
–
–
–
–
–
–
200
–
±4
1.235
–
V
30% VDD V
–
V
20%VDD V
–
MΩ
–
kΩ
4.0 kΩ
–
kΩ
200 Ω
–
µA
–
V
Dynamic Values
Encoder Analog Signal Input Sensitivity
VDD = 3.0V
2
-37
–
4.0 dB
VDD = 5.0V
2
-37
–
4.0 dB
Encoder Input to Decoder Output Insertion
Loss
VDD = 3.0V
VDD = 5.0V
Encoder/Decoder (Full Codec)
2
-
0
-
dB
2
-
0
-
dB
Passband Lowest Corner Frequency
3
-
2900
–
Hz
Passband Highest Corner Frequency
3
–
1400
-
Hz
Stopband Lowest Corner Frequency
3
-
6.0
–
kHz
Stopband Highest Corner Frequency
3
–
24
-
kHz
Stopband Attenuation
–
40
–
dB
Passband Gain
–
0
–
dB
Passband Ripple
5
-1.5
–
3.0 dB
Output Noise (Input Short Circuit)
4,6
–
-61
-
dBmOp
Perfect Idle Channel Noise (Encode Forced)
4,6
–
-62
-
dBmOp
Notes:
1. Not including any current drawn from the device by external circuits.
2. Input and output signal levels are independent of supply voltage.
3. Passband and stopband corner frequencies are programmable. Specified values are at
nominal crystal frequencies of 4.096, 8.192, 12.288, or 16.384Mhz with the master clock
divider configured for a divide by 1, 2, 3, or 4 respectively. For other crystal frequencies
passband and stopband corner frequencies must be scaled accordingly.
4. dBmOp units imply the use of a psophometrically weighted filter that is commonly used
in voice communication applications per ITU Recommendation G.223.
5. From 400Hz to 3000Hz with a 3.7kHz bandwidth.
6. At VDD =2.7Vm, data rate = 64kbps, 2.9kHz bandwidth, offsets compensated and 1st
order integration only.
© 2003 CML Microsystems Plc
45
D/649/2
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