AD9863 Analog Devices, AD9863 Datasheet - Page 14

• Manufacturer Part Number: AD9863
• Description: 12-Bit Mixed-Signal Front-End (MxFE® )Processor For Broadband Applications
• Manufacturer: Analog Devices

Specifications of AD9863

• Resolution (bits): 12bit
• # Chan: 2
• Sample Rate: 50MSPS
• Interface: Par
• Analog Input Type: Diff-Uni
• Ain Range: 2 V p-p
• Adc Architecture: Pipelined
• Pkg Type: CSP

AD9863
Figure 28 to Figure 33 use the same input data to the Tx path, a 64-carrier OFDM signal over a 20 MHz bandwidth, centered at 20 MHz.
The two center carriers are removed from the signal to observe the in-band intermodulation distortion (IMD) from the DAC output.
Figure 28. AD9863 Tx Path FFT, 64-Carrier (Two Center Carriers Removed)
OFDM Signal over 20 MHz Bandwidth, Centered at 20 MHz, with
Figure 30. AD9863 Tx Path FFT of OFDM Signal in Figure 28 with
–100
–110
–120
–100
–110
–120
–100
–110
–120
–20
–30
–40
–50
–60
–70
–80
–90
–20
–30
–40
–50
–60
–70
–80
–90
–20
–30
–40
–50
–60
–70
–80
–90
Figure 29. AD9863 Tx Path FFT, Lower-Band IMD Products of
7.5
7.5
0
20 mA Full-Scale Output into 60 Ω Differential Load
8.0
10
12.5
8.5
20
OFDM Signal in Figure 28
9.0
1x Interpolation
FREQUENCY (MHz)
FREQUENCY (MHz)
FREQUENCY (MHz)
30
17.5
9.5
10.0
40
22.5
10.5
50
11.0
60
27.5
11.5
70
12.0
32.5
12.5
80
Rev. A| Page 14 of 40
–100
–110
–120
–100
–110
–120
–100
–110
–120
–20
–30
–40
–50
–60
–70
–80
–90
–20
–30
–40
–50
–60
–70
–80
–90
–20
–30
–40
–50
–60
–70
–80
–90
Figure 32. AD9863 Tx Path FFT, Lower-Band IMD Products of
18.75
27.5
Figure 31. AD9863 Tx Path FFT, In-Band IMD Products of
0
Figure 33. AD9863 Tx Path FFT of OFDM Signal in
28.0
10
19.25
28.5
Figure 28 with 2x Interpolation
20
OFDM Signal in Figure 28
OFDM Signal in Figure 28
29.0
FREQUENCY (MHz)
FREQUENCY (MHz)
FREQUENCY (MHz)
19.75
30
29.5
30.0
40
20.25
30.5
50
31.0
60
20.75
31.5
70
32.0
21.25
32.5
80