AD9778ABSVZ Analog Devices Inc, AD9778ABSVZ Datasheet - Page 31

• Manufacturer Part Number: AD9778ABSVZ
• Description: IC,D/A CONVERTER,DUAL,14-BIT,CMOS,TQFP,100PIN
• Manufacturer: Analog Devices Inc

Specifications of AD9778ABSVZ

• Number Of Bits: 14
• Data Interface: Parallel
• Number Of Converters: 2
• Voltage Supply Source: Analog and Digital
• Power Dissipation (max): 300mW
• Operating Temperature: -40°C ~ 85°C
• Mounting Type: Surface Mount
• Package / Case: 100-TQFP Exposed Pad, 100-eTQFP, 100-HTQFP, 100-VQFP
• Package: 100TQFP EP
• Resolution: 14 Bit
• Conversion Rate: 1 GSPS
• Architecture: Interpolation Filter
• Digital Interface Type: Parallel
• Number Of Outputs Per Chip: 2
• Output Type: Current
• Full Scale Error: ±2(Typ) %FSR
• Integral Nonlinearity Error: ±1.5(Typ) LSB
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• For Use With: AD9778A-EBZ - BOARD EVALUATION AD9778A
• Settling Time: -
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

INTERPOLATION FILTER ARCHITECTURE
The AD9776A/AD9778A/AD9779A can provide up to 8× inter-
polation, or the interpolation filters can be entirely disabled. It
is important to note that the input signal should be backed off
by approximately 0.01 dB from full scale to avoid overflowing
the interpolation filters. The coefficients of the low-pass filters
and the inverse sinc filter are given in Table 15, Table 16, Table 17,
and Table 18. Spectral plots for the filter responses are shown in
Figure 57, Figure 58, and Figure 59.
Table 15. Low-Pass Filter 1
Lower Coefficient
H(1)
H(2)
H(3)
H(4)
H(5)
H(6)
H(7)
H(8)
H(9)
H(10)
H(11)
H(12)
H(13)
H(14)
H(15)
H(16)
H(17)
H(18)
H(19)
H(20)
H(21)
H(22)
H(23)
H(24)
H(25)
H(26)
H(27)
H(28)
Upper Coefficient
H(55)
H(54)
H(53)
H(52)
H(51)
H(50)
H(49)
H(48)
H(47)
H(46)
H(45)
H(44)
H(43)
H(42)
H(41)
H(40)
H(39)
H(38)
H(37)
H(36)
H(35)
H(34)
H(33)
H(32)
H(31)
H(30)
H(29)
Integer Value
−4
0
+13
0
−34
0
+72
0
−138
0
+245
0
−408
0
+650
0
−1003
0
+1521
0
−2315
0
+3671
0
−6642
0
+20,755
+32,768
Rev. A | Page 31 of 60
Table 16. Low-Pass Filter 2
Lower Coefficient
H(1)
H(2)
H(3)
H(4)
H(5)
H(6)
H(7)
H(8)
H(9)
H(10)
H(11)
H(12)
Table 17. Low-Pass Filter 3
Lower Coefficient
H(1)
H(2)
H(3)
H(4)
H(5)
H(6)
H(7)
H(8)
Table 18. Inverse Sinc Filter
Lower Coefficient
H(1)
H(2)
H(3)
H(4)
H(5)
Figure 57. 2× Interpolation, Low-Pass Response to ±4× Input Data Rate
–100
–10
–20
–30
–40
–50
–60
–70
–80
–90
10
0
–4
–3
(Dotted Lines Indicate 1 dB Roll-Off)
AD9776A/AD9778A/AD9779A
–2
Upper Coefficient
H(15)
H(14)
H(13)
H(12)
H(11)
H(10)
H(9)
Upper Coefficient
H(9)
H(8)
H(7)
H(6)
Upper Coefficient
H(23)
H(22)
H(21)
H(20)
H(19)
H(18)
H(17)
H(16)
H(15)
H(14)
H(13)
f
OUT
–1
(× Input Data Rate)
0
1
Integer Value
−39
0
+273
0
−1102
0
+4964
+8192
Integer Value
+2
−4
+10
−35
+401
2
Integer Value
−2
0
+17
0
−75
0
+238
0
−660
0
+2530
+4096
3
4