AD9861 Analog Devices, AD9861 Datasheet - Page 19

• Manufacturer Part Number: AD9861
• Manufacturer: Analog Devices

Specifications of AD9861

• Resolution (bits): 10bit
• # Chan: 2
• Sample Rate: 80MSPS
• Interface: Par
• Analog Input Type: Diff-Uni
• Ain Range: 2 V p-p
• Adc Architecture: Pipelined
• Pkg Type: CSP

Figure 58 to Figure 63 use the same input data to the Tx path, a 256-carrier OFDM signal over a 1.75 MHz bandwidth, centered at 7 MHz.
The center four carriers are removed from the signal to observe the in-band intermodulation distortion (IMD) from the DAC output.
Figure 58. AD9861 Tx Path FFT, 256-Carrier (Center Four Carriers Removed)
OFDM Signal over 1.75 MHz Bandwidth, Centered at 7 MHz, with
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Figure 59. AD9861 Tx Path FFT, Lower-Band IMD Products of
Figure 60. AD9861 Tx Path FFT of OFDM Signal in Figure 52,
6.06
6.0
0
20 mA Full-Scale Output into 60 Ω Differential Load
6.2
6.08
5
6.4
OFDM Signal in Figure 58
with 1× Interpolation
6.6
6.10
FREQUENCY (MHz)
FREQUENCY (MHz)
FREQUENCY (MHz)
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6.8
6.12
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8.0
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Figure 62. AD9861 Tx Path FFT, Upper-Band IMD Products of
Figure 63. AD9861 Tx Path FFT of OFDM Signal in Figure 52,
6.97
7.81
Figure 61. AD9861 Tx Path FFT, In-Band IMD Products of
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7.83
6.98
5
OFDM Signal in Figure 58
OFDM Signal in Figure 52
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with 4× Interpolation
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FREQUENCY (MHz)
FREQUENCY (MHz)
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FREQUENCY (MHz)
7.87
7.00
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AD9861
7.93
7.03