CS4237B Datasheet, PDF (95/114 Pages) Cirrus Logic – CrystalClear Advanced Audio System with 3D Sound

ferrite bead to the VD1 supply as shown in the
Reference Design Data Sheet. These pins must
be connected to a 5V supply.
VA provides power to the sensitive analog sec-
tions of the chip and should have a clean,
regulated supply to minimize power supply cou-
pled noise in the analog inputs and outputs.
ADC/DAC FILTER RESPONSE PLOTS
Figures 34 through 39 show the overall fre-
quency response, passband ripple, and transition
band for the ADCs and DACs. Figure 40 shows
the DACs’ deviation from linear phase. Since the
filter response scales based on sample frequency
selected, all frequency response plots x-axis are
shown from 0 to 1, where 1 is equivalent to Fs.
Therefore, for any given sample frequency, mul-
tiply the x-axis values by the sample frequency
selected to get the actual frequency.
CS4237B
10
0
-10
-20
-30
-40
-50
-60
-70
-80
-90
-100
0.0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0
Input Frequency ( x Fs)
Figure 34. ADC Filter Response
0.2
0.1
0.0
-0.1
-0.2
-0.3
-0.4
-0.5
-0.6
-0.7
-0.8
0.00 0.05 0.10 0.15 0.20 0.25 0.30 0.35 0.40 0.45 0.50
Input Frequency ( x Fs)
Figure 35. ADC Passband Ripple
DS213PP4
0
-10
-20
-30
-40
-50
-60
-70
-80
-90
-100
0.40
0.45
0.50
0.55
0.60
0.65
0.70
Input Frequency ( x Fs)
Figure 36. ADC Transition Band
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