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FS781/82/84
Document #: 38-07029 Rev. *F Page 3 of 12
Table 2. FS781/82/84 Recommended Loop Filter Values C7 (pF) @ +3.3 VDC ±5% (R6 = 3.3K)
[1, 2, 3, 4]
Input MHz S1 S0 BW = 1.0%
[3]
BW = 1.5%
[3]
BW = 2.0%
[3]
BW = 2.5%
[3]
BW = 3.0%
[3]
BW = 3.5%
[3]
BW = 4.0%
[3]
6 0 0 10,000/1000 1550 910 780 700 640 560
8 0 0 10,000/330 990 820 640 520 450 400
10 0 0 1040 680 460 360 300 240 210
12 0 0 830 420 300 220 200 190 170
14 0 0 580 230 200 160 140 100 80
16 0 1 10000 980 760 580 470 410 385
18 0 1 1200 750 580 470 415 370 300
20 0 1 1000 730 470 390 320 220 190
22 0 1 960 640 410 270 230 200 180
24 0 1 920 400 250 210 180 160 150
26 0 1 660 300 220 180 150 140 120
28 0 1 470 230 180 150 130 100 70
30 0 1 470 180 140 120 100 80 60
32 0 1 330 170 120 100 82 68 47
34 1 0 10000 860 640 520 430 380 330
36 1 0 2200 820 620 470 400 330 290
38 1 0 1500 690 520 410 340 290 240
40 1 0 960 600 420 340 280 220 160
42 1 0 940 620 380 275 230 210 180
44 1 0 950 680 400 250 210 190 170
46 1 0 900 580 270 220 190 180 165
48 1 0 790 440 260 210 180 160 140
50 1 0 660 360 250 190 170 150 140
52 1 0 470 325 220 185 155 135 120
54 1 0 470 270 200 170 140 130 100
56 1 0 445 250 185 150 120 85 47
58 1 0 430 210 165 130 100 65 33
60 1 0 295 185 150 120 100 90 82
62 1 0 270 220 150 120 100 82 68
64 1 1 1180 860 560 410 340 290 230
65 1 1 1180 850 540 400 330 280 220
66 1 1 1180 760 560 350 260 220 210
68 1 1 1180 750 500 320 260 230 210
70 1 1 1120 740 470 370 300 240 170
72 1 1 1160 780 470 300 250 220 190
74 1 1 1110 770 470 280 230 210 190
76 1 1 1000 720 440 240 210 190 170
78 1 1 910 670 270 210 190 170 160
80 1 1 900 620 260 210 190 170 156
82 1 1 900 540 250 210 190 170 150
Notes:
1. If the value selected from the above chart is not a standard, use the next available larger value.
2. All bandwidths indicated above are total peak-to-peak spread. 1% = +0.5% to –0.5%. 4% = +2.0% to –2.0%.
3. If C8 is not listed in the chart for a particular bandwidth and frequency, it is not used in the loop filter.
4. Contact Cypress for LF values less than 1.0% bandwidth.
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