Datasheet
Data Sheet AD7762
Rev. A | Page 11 of 28
05477-060
FREQUENCY (Hz)
AMPLITUDE (dB)
–
25
0
–50
–
75
–100
–125
–
150
–
175
–
200
600000
120000
180000
240000
300000
Figure 11. Normal Mode FFT, 100 kHz, −0.5 dB Input Tone, 32× Decimation
05477-061
FREQUENCY (Hz)
AMPLITUDE (dB)
–
25
0
–
50
–75
–100
–
125
–
150
–175
–
200
60000
0 120000 180000
240000
300000
Figure 12. Normal Mode FFT, 100 kHz, −6 dB Input Tone, 32× Decimation
05477-062
DECIMATION RATE (x)
SNR (dBFS)
120
106
0 256
118
116
114
112
110
108
64 128 192
–
0.5dB
–60dB
–
6dB
Figure 13. Normal Mode SNR vs. Decimation Rate, 1 kHz Input Tone
05477-063
FREQUENCY (Hz)
AMPLITUDE (dB)
–
25
0
–50
–
75
–
100
–125
–
150
–
175
–
200
600000
120000 180000
240000
300000
Figure 14. Low Power FFT, 100 kHz, −0.5 dB Input Tone, 32× Decimation
05477-064
FREQUENCY (Hz)
AMPLITUDE (dB)
–
25
0
–50
–
75
–100
–
125
–
150
–
175
–200
60000
0 120000
180000
240000 300000
Figure 15. Low Power FFT, 100 kHz, −6 dB Input Tone, 32× Decimation
05477-065
DECIMATION RATE (x)
SNR (dBFS)
116
104
0 25664 128
192
112
108
–60dB
–0.5dB
–6dB
Figure 16. Low Power SNR vs. Decimation Rate, 1 kHz Input Tone