Analog Devices AD9779 Preliminary Technical Data page 20

AD9779
Interp. Filter Filter1 mode
(Mode_F1)
Factor Mode
<7:6> <5:2>
8 00h 0
8 01h 1
8 02h 2
8 03h 3
8 04h 0
8 05h 1
8 06h 2
8 07h 3
8 08h 0
8 09h 1
8 0Ah 2
8 0Bh 3
8 0Ch 0
8 0Dh 1
8 0Eh 2
8 0Fh 3
4 00h 0
4 01h 1
4 02h 2
4 03h 3
4 04h 0
4 05h 1
4 06h 2
4 07h 3
2 00h 0
2 01h 1
2 02h 2
2 03h 3
Filter2 mode Filter3 mode
(Mode_F2) (Mode_F3)
0 0
1 0
2 1
3 2
4 2
5 2
6 3
7 4
0 4
1 4
2 5
3 6
4 6
5 6
6 7
7 0
0 OFF
1 OFF
2 OFF
3 OFF
4 OFF
5 OFF
6 OFF
7 OFF
OFF OFF
OFF OFF
OFF OFF
OFF OFF
Table 13: Interpolation Filter Modes, see Reg 01, bits 5 :2
Rev. PrD | Page 20 of 34
Preliminary Technical Data
Modulation Nyquist F_low
Zone
Passband
(Freq. Normalized to F
DC_odd 1 -0.05
DC_even 2 0.0125
F/8_odd 3 0.075
F/8_even 4 0.1375
2F/8_odd 5 0.2
2F/8_even 6 0.2625
3F/8_odd 7 0.325
3F/8_even 8 0.3875
-4F/8_even -8 0.45
-4F/8_odd -7 0.5125
-3F/8_even -6 0.575
-3F/8_odd -5 0.6375
-2F/8_even -4 0.7
-2F/8_odd -3 0.7625
-F/8_even -2 0.825
-F/8_odd -1 0.8875
DC_odd 1 -0.1
DC_even 2 0.025
F/4_odd 3 0.15
F/4_even 4 0.275
-F/2_even -4 0.4
-F/2_odd -3 0.525
-F/4_even -2 0.65
-F/4_odd -1 0.775
DC_odd 1 -0.2
DC_even 2 0.05
-F/2_even -1 0.3
-F/2_odd -2 0.55
Center F_High
)
DAC
0 0.05 In 8x
interpolation,
BW=0.0375-
0.0625 0.1125
(0.1* F
DAC
0.125 0.175
Worst case:
F/32
0.1875 0.2375
0.25 0.3
0.3125 0.3625
0.375 0.425
0.4375 0.4875
0.5 0.55
0.5625 0.6125
0.625 0.675
0.6875 0.7375
0.75 0.8
0.8125 0.8625
0.875 0.925
0.9375 0.9875
0 0.1 In 8x
interpolation,
BW=0.075-(0.2*
0.125 0.225
F )
DAC
0.25 0.35
Worst case:
F/16
0.375 0.475
0.5 0.6
0.625 0.725
0.75 0.85
0.875 0.975
0 0.2 In 2x
Interpolation
0.25 0.45
BW=0.15-0.4
F
DAC
0.5 0.7
Worst case: F/8
0.75 0.95
)