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16 illustra, Cs5581 – Cirrus Logic CS5581 User Manual

Page 22

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CS5581

22

DS796PP1

3/25/08

14:34

Figure 16 illustrates the noise floor of the converter from 0.1 Hz to 100 kHz. While the plot does exhibit
some 1/f noise at lower frequencies, the noise floor is entirely free of spurious frequency content due to
digital activity inside the chip.

Figure 17 illustrates a noise histogram of 4096 samples.

-160

-140

-120

-100

-80

-60

-40

-20

0

0.1

1

10

100

1k

10k

100k

Frequency (Hz)

Shorted Input
2M Samples @ 200 kSps
16 Averages

Figure 16. Spectral Plot of Noise with Shorted Input

0

100

200

300

400

500

600

700

800

900

-8

-7

-6

-5

-4

-3

-2

-1

0

1

2

3

4

5

6

7

8

Mean = -0.61
Std. Dev = 2.33

Output (Codes)

Figure 17. Noise Histogram (4096 Conversions)