Datasheet

AD9201
–11–
REV. D
QREFT
QREFB
IREFT
0.1mF
10mF
0.1mF
0.1mF
AD9201
REFSENSE
AVSS
1V
0.1mF10mF
IREFB
VREF
0.1mF
0.1mF
10kV
10kV
ADC
CORE
INTERNAL
CONTROL
LOGIC
10mF 0.1mF
Figure 26. Reference Buffer Equivalent Circuit and Exter-
nal Decoupling Recommendation
For best results in both noise suppression and robustness
against crosstalk, the 4 capacitor buffer decoupling arrangement
shown in Figure 26 is recommended. This decoupling should
feature chip capacitors located close to the converter IC. The
capacitors are connected to either IREFT/IREFB or QREFT/
QREFB. A connection to both sides is not required.
DRIVING THE AD9201
Figure 27 illustrates the use of an AD8051 to drive the AD9201.
Even though the AD8051 is specified with 3 V and 5 V power,
the best results are obtained at ±5 V power. The ADC input
span is 2 V.
ADC
17
16
1kV
VREF
AD8051
3
2
50V
1kV
1kV
6
22V
22V
0.33mF
0.01mF
10pF
10pF
24V
Figure 27.
–120
–110
–100
–90
–80
–70
–60
–50
–40
–30
–20
–10
0
10
0.0E+0 2.0E+6
1.0E+6
4.0E+6 6.0E+6 8.0E+6 10.0E+6
3.0E+6 5.0E+6 7.0E+6 9.0E+6
FUND
2ND 3RD
4TH
5TH
6TH
7TH
8TH
Figure 28. AD8051/AD9201 Performance