AD8345
CHARACTERIZATION SETUPS
SSB SETUP
Essentially, two primary setups are used to characterize the
AD8345. These setups are shown in Figure 37 and Figure 38.
Figure 37 shows the setup used to evaluate the product as a
single sideband modulator. The interface board converts the
single-ended I and Q inputs from the arbitrary function
generator to differential inputs with a dc bias of approximately
0.7 V. The interface board also provides connections for power
supply routing. The HP34970A and its associated plug-in 34901
are used to monitor power supply currents and voltages being
supplied to the AD8345 characterization board. Two HP34907
plug-ins are used to provide additional miscellaneous dc and
control signals to the interface board. The LO inputs are driven
directly by an RF signal generator, and the output is measured
directly with a spectrum analyzer. With the I channel driven
with a sine wave and the Q channel driven with a cosine wave,
the lower sideband is the single sideband output. The typical
SSB output spectrum is shown in Figure 36.
0
–10
–20
–30
–40
–50
–60
–70
–80
–90
–100
CENTER = 900MHz
SPAN = 1MHz
Figure 36. Typical SSB Output Spectrum
IEEE
D1
HP34970A
D2
D3
34901
D1
34907
D2
34907
D3
TEKAFG2020
+15V MAX
COM
VPS1
I_IN
OUTPUT_1
OUTPUT_2
INTERFACE
BOARD
IEEE
IEEE
+25V MAX
–25V MAX
Q_IN
VN
GND
VP
ARB FUNCTION GEN
HP3631
P1 IN IP QP QN
IP
QP
QN
IN
AD8345
HP8648C
CHARACTERIZATION
BOARD
HP8593E
LO
IEEE
RFOUT
SWEEP OUT
VOUT
RF I/P
ENBL
28V
P1
SPECTRUM
ANALYZER
IEEE
IEEE
PC CONTROLLER
Figure 37. Characterization Board SSB Test Setup
Rev. B | Page 17 of 20
ADI [ ADI ]
