Cirrus Logic AN339 - Manual (Page 7)

AN339
AN339REV1
AN339REV1 7
6.2 Full-Scale FFTs
FFTs of the 997 Hz and 18 kHz test cases are provided below. These show the differences in the tonal and
noise signatures of the converters when clocked from the CS8413/14 and the CS8416 in each PDUR mode.
-160
+0
-150
-140
-130
-120
-110
-100
-90
-80
-70
-60
-50
-40
-30
-20
-10
d
B
r
A
20 20k 50 100 200 500 1k 2k 5k 10k
Hz
CS8414
CS8416 PDUR=0
CS8416 PDUR=1
Figure 18. FFT - 0 dBFS, 997 Hz
Fs = 48 kHz
-160
+0
-150
-140
-130
-120
-110
-100
-90
-80
-70
-60
-50
-40
-30
-20
-10
d
B
r
A
20 20k 50 100 200 500 1k 2k 5k 10k
Hz
CS8414
CS8416 PDUR=0
CS8416 PDUR=1
Figure 19. FFT - 0 dBFS, 18 kHz
Fs = 48 kHz
-160
+0
-150
-140
-130
-120
-110
-100
-90
-80
-70
-60
-50
-40
-30
-20
-10
d
B
r
A
20 20k 50 100 200 500 1k 2k 5k 10k
Hz
-160
+0
-150
-140
-130
-120
-110
-100
-90
-80
-70
-60
-50
-40
-30
-20
-10
d
B
r
A
20 20k 50 100 200 500 1k 2k 5k 10k
Hz
CS8414
CS8416 PDUR=0
CS8416 PDUR=1
Figure 20. FFT - 0 dBFS, 997 Hz
Fs = 96 kHz
Figure 21. FFT - 0 dBFS, 18 kHz
Fs = 96 kHz
CS8414
CS8416 PDUR=0
CS8416 PDUR=1
-160
+0
-150
-140
-130
-120
-110
-100
-90
-80
-70
-60
-50
-40
-30
-20
-10
d
B
r
A
20 20k 50 100 200 500 1k 2k 5k 10k
Hz
-160
+0
-150
-140
-130
-120
-110
-100
-90
-80
-70
-60
-50
-40
-30
-20
-10
d
B
r
A
20 20k 50 100 200 500 1k 2k 5k 10k
Hz
Figure 22. FFT - 0 dBFS, 997 Hz
Fs = 192 kHz
Figure 23. FFT - 0 dBFS, 18 kHz
Fs = 192 kHz
CS8414 (48 kHz)
CS8416 PDUR=0
CS8414 (48 kHz)
CS8416 PDUR=0