ISL5416_04 Datasheet, PDF (68/71 Pages) Intersil Corporation – Four-Channel Wideband Programmable DownConverter

ISL5416
0.0
-1.0
-2.0
N=1
-3.0
N=2
-4.0
N=5
-5.0
N=3
N=4
-6.0
0.0
0.1
0.2
0.3
0.4
0.5
f_S/R
FIGURE 19. CIC PASSBAND ROLLOFF (N = # OF STAGES,
R = DECIMATION FACTOR, f_S/R = 1 is CIC
OUTPUT RATE)
0
N=1
-20
-40
-60
-80
N=2
-100
-120
N=3
N=4
N=5
-140
0.00
0.10
0.20
0.30
0.40
0.50
f_S/R
FIGURE 19A. CIC FIRST ALIAS LEVEL (N = # OF STAGES,
R = DECIMATION FACTOR, f_S/R = 1 is CIC
OUTPUT RATE)
0
-20
-40
-60
-80
-100
-120
-140
-160
-180
0
1
2
3
4
5
6
x 10⁴
FIGURE 20. A TYPICAL CARRIER NCO SPECTRUM
PLOT (65536 POINT FFT, BLACKMAN WINDOW,
800 Hz BIN NBW (29 dB). PEAK BIN IS AT -132
dBc, NOISE FLOOR AT -190 dBc/Hz.
0
-20
-40
-60
-80
-100
-120
-140
0.0
0.5
1.0
1.5
2.0
2.5
3.0
f_S/R
FIGURE 19B. 5TH ORDER (N = 5) CIC RESPONSE
(R = DECIMATION FACTOR, f_S/R = 1 is CIC
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