CS4239 Datasheet, PDF (80/98 Pages) Cirrus Logic – CrystalClear™ Portable ISA Audio System

CS4239
CrystalClear^TM Portable ISA Audio System
ADC/DAC FILTER RESPONSE PLOTS
Figures 26 through 31 show the overall fre-
quency response, passband ripple, and transition
band for the ADCs and DACs. Figure 32 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.
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 26. 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 27. ADC Passband Ripple
80
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 28. ADC Transition Band
DS253PP2