Datasheet

AD9258
Rev. A | Page 22 of 44
0
–20
–40
–60
–80
–100
–120
–140
0 102030405060
FREQUENCY (MHz)
AMPLITUDE (dBFS)
08124-022
125MSPS
70.1MHz @ –6dBFS
SNR = 71.6dB (77.6dBFS)
SFDR = 97dBc
SECOND HARMONIC
THIRD HARMONIC
Figure 38. AD9258-125 Single-Tone FFT with f
IN
= 70.1 MHz @ −6 dBFS
with Dither Enabled
0
–15
–30
–45
–60
–75
–90
–105
–120
–135
–150
FREQUENCY (MHz)
AMPLITUDE (dBFS)
08123-088
SECOND HARMONIC
THIRD HARMONIC
0 6 12 18 24 30 36 42 48 54 60
125MSPS
70.1MHz @ –23dBFS
SNR = 56.1dB (79.1dBFS)
SFDR = 67.7dBc
Figure 39. AD9258-125 Single-Tone FFT with f
IN
= 70.1 MHz @ −23 dBFS
with Dither Disabled, 1M Sample
0 6 12 18 24 30 36 42 48 54 60
FREQUENCY (MHz)
AMPLITUDE (dBFS)
08123-089
SECOND HARMONIC
THIRD HARMONIC
0
–15
–30
–45
–60
–75
–90
–105
–120
–135
–150
125MSPS
70.1MHz @ –23dBFS
SNR = 55.4dB (78.4dBFS)
SFDR = 86.2dBc
Figure 40. AD9258-125 Single-Tone FFT with f
IN
= 70.1 MHz @ −23 dBFS
with Dither Enabled, 1M Sample
120
100
80
60
40
20
0
–100 –90 –80 –70 –60 –50 –40 –30 –20 –10 0
INPUT AMPLITUDE (dBFS)
SNR/SFDR (dBc AND dBFS)
08124-023
SNR (dBFS)
SFDR (dBc)
SNR (dBc)
SFDR (dBFS)
Figure 41. AD9258-125 Single-Tone SNR/SFDR vs. Input Amplitude (A
IN
)
with f
IN
= 2.4 MHz
120
100
80
60
40
20
0
–100 –90 –80 –70 –60 –50 –40 –30 –20 –10 0
INPUT AMPLITUDE (dBFS)
SNR/SFDR (dBc AND dBFS)
08124-024
SNR (dBFS)
SFDR (dBc)
SFDR (dBFS)
SNR (dBc)
Figure 42. AD9258-125 Single-Tone SNR/SFDR vs. Input Amplitude (A
IN
)
with f
IN
= 98.12 MHz
120
110
100
90
80
70
–100 –90 –80 –70 –60 –50 –40 –30 –20 –10 0
INPUT AMPLITUDE (dBFS)
SNR/SFDR (dBFS)
08124-061
SNR (DITHER ON)
SNR (DITHER 0FF)
SFDR (DITHER ON)
SFDR (DITHER 0FF)
Figure 43. AD9258-125 Single-Tone SNR/SFDR vs. Input Amplitude (A
IN
)
with f
IN
= 30 MHz with and without Dither Enabled