EXAR XRDAN28

XRDAN28
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Introduction
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Example I (See Figure 1.)
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DOUT (s)/DIN (s)=(1•exp(•N*s/F S ))/(N(1•exp(•s/F S )))
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Example II (see Figure 2.)
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XRDAN28
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3 12&
0 12-
Equivalent Systems
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30MHz
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D OUT (S)
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A IN (S)
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2
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Figure 1. Two Samples Averaged
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53 12&
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Equivalent Systems
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D OUT (S)
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A IN (S)
1 • (1 + e
4
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30 MHz
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30 MHz
• 3• S
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Figure 2. Four Samples Averaged
XRDAN28
A/D SAMPLE RATE•30 MHz
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12DOUT2
12DOUT4
12-
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Graph 1. Decimation Filter Frequency Response
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312-
>12-
XRDAN28
Notes
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