Datasheet

Data Sheet AD9518-3
Rev. B | Page 17 of 64
1.9
1.7
1.5
1.3
1.1
0.9
1.71.81.92.02.12.22.3
VCO TUNING VOLTAGE (V)
VCO FREQUENCY (GHz)
06432-138
Figure 11. VCO Tuning Voltage vs. Frequency
(Note that VCO calibration centers the dc tuning voltage
for the PLL setup that is active during calibration.)
–110
–100
–90
–80
–70
–60
–50
–40
–30
–20
–10
10
0
CENTER 122.88MHz SPAN 50MHz5MHz/DIV
RELATIVE POWER (dB)
06432-137
Figure 12. PFD/CP Spurs; 122.88 MHz; PFD = 15.36 MHz;
LBW = 127 kHz; I
CP
= 3.0 mA; f
VCO
= 2.21 GHz
–110
–100
–90
–80
–70
–60
–50
–40
–30
–20
–10
10
0
CENTER 122.88MHz SPAN 1MHz100kHz/DIV
RELATIVE POWER (dB)
06432-135
Figure 13. Output Spectrum, LVPECL; 122.88 MHz; PFD = 15.36 MHz;
LBW = 127 kHz; I
CP
= 3.0 mA; f
VCO
= 2.21 GHz
1.0
0.6
0.2
–0.2
–0.6
–1.0
022015105
DIFFERENTIAL OUTPUT (V)
TIME (ns)
5
06432-014
Figure 14. LVPECL Output (Differential) at 100 MHz
1.0
0.6
0.2
–0.2
–0.6
–1.0
021
DIFFERENTIAL OUTPUT (V)
TIME (ns)
06432-015
Figure 15. LVPECL Output (Differential) at 1600 MHz
1600
800
1000
1200
1400
0321
DIFFERENTIAL SWING (mV p-p)
FREQUENCY (GHz)
06432-020
Figure 16. LVPECL Differential Swing vs. Frequency,
Using a Differential Probe Across the Output Pair