Datasheet
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f/f
IN
−160
−140
−120
−100
−80
−60
−40
−20
0
20
0.0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0
Magnitude – dB
G048
f
OUT
/f
DAC
−4
−3
−2
−1
0
1
2
3
4
0.0 0.1 0.2 0.3 0.4 0.5
Magnitude – dB
Sin(x)/x
FIR4
Corrected
G049
DAC5687
SLWS164E – FEBRUARY 2005 – REVISED SEPTEMBER 2006
Figure 37. Magnitude Spectrum for FIR2 Figure 38. Magnitude Spectrum for Inverse Sinc Filter
FIR4 (Versions 1 and 2)
Table 8. Digital Filter Taps
FIR1 and FIR3 FIR2 FIR4 (Invsinc)
Tap Coeff Tap Coeff Tap Coeff
1, 51 8 1, 19 9 1, 9 1
2, 50 0 2, 18 0 2, 8 – 4
3, 49 – 24 3, 17 – 58 3, 7 13
4, 48 0 4, 16 0 4, 6 – 50
5, 47 58 5, 15 214 5 592
6, 46 0 6, 14 0
7, 45 – 120 7, 13 – 638
8, 44 0 8, 12 0
9, 43 221 9, 11 2521
10, 42 0 10 4096
11, 41 – 380
12, 40 0
13, 39 619
14, 38 0
15, 37 – 971
16, 36 0
17, 35 1490
18, 34 0
19, 33 – 2288
20, 32 0
21, 31 3649
22, 30 0
23, 29 – 6628
24, 28 0
25, 27 20,750
26 32,768
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