Datasheet

AD9776A/AD9778A/AD9779A
Rev. B | Page 36 of 56
Table 19. Interpolation Filter Modes, (Register 0x01, Bits[5:2])
Interpolation
Factor[7:6]
Filter Modulation
Mode[5:2]
Modulation
Nyquist Zone
Pass Band
Frequency Normalized to f
DAC
Comments
Low Center High
8 0x00 DC 0 −0.05 0 +0.05
In 8× interpolation;
BW (min) = 0.0375 × f
DAC
BW (max) = 0.1 × f
DAC
8 0x01 DC shifted +1 +0.0125 +0.0625 +0.1125
8 0x02 f
DAC
/8 +2 +0.075 +0.125 +0.175
8 0x03 f
DAC
/8 shifted +3 +0.1375 +0.1875 +0.2375
8 0x04 f
DAC
/4 +4 +0.2 +0.25 +0.3
8 0x05 f
DAC
/4 shifted +5 +0.2625 +0.3125 +0.3625
8 0x06 3f
DAC
/8 +6 +0.325 +0.375 +0.425
8 0x07 3f
DAC
/8 shifted +7 +0.3875 +0.4375 +0.4875
8 0x08 f
DAC
/2 ±8 −0.55 −0.5 −0.45
8 0x09 f
DAC
/2 shifted −7 −0.4875 −0.4375 −0.3875
8 0x0A −3f
DAC
/8 −6 −0.425 −0.375 −0.343
8 0x0B −3f
DAC
/8 shifted −5 −0.3625 −0.3125 −0.2625
8 0x0C −f
DAC
/4 −4 −0.3 −0.25 −0.2
8 0x0D −f
DAC
/4 shifted −3 −0.2375 −0.1875 −0.1375
8 0x0E −f
DAC
/8 −2 −0.175 −0.125 −0.075
8 0x0F −f
DAC
/8 shifted −1 −0.1125 −0.0625 −0.0125
4 0x00 DC 0 −0.1 0 +0.1
In 4× interpolation;
BW (min) = 0.075 × f
DAC
BW (max) = 0.2 × f
DAC
4 0x01 DC shifted +1 +0.025 +0.125 +0.225
4 0x02 f
DAC
/4 +2 +0.15 +0.25 +0.35
4 0x03 f
DAC
/4 shifted +3 +0.275 +0.375 +0.475
4 0x04 f
DAC
/2 ±4 −0.6 −0.5 −0.4
4 0x05 f
DAC
/2 shifted −3 −0.475 −0.375 −0.275
4 0x06 −f
DAC
/4 −2 −0.35 −0.25 −0.15
4 0x07 −f
DAC
/4 shifted −1 −0.225 −0.125 −0.025
2 0x00 DC 0 −0.2 0 +0.2
In 2× interpolation;
BW (min) = 0.15 × f
DAC
BW (max) = 0.4 × f
DAC
2 0x01 DC shifted +1 +0.05 +0.25 +0.45
2 0x02 f
DAC
/2 ±2 −0.7 −0.5 −0.3
2 0x03 f
DAC
/2 shifted −1 −0.45 −0.25 −0.05