CN-0248 Datasheet, PDF (5/6 Pages) Analog Devices – An IQ Demodulator-Based IF-to-Baseband Receiver with IF and Baseband Variable Gain and Programmable Baseband Filtering

Circuit Note
CN-0248
Getting Started
To use the ADL5336 and ADRF6510, the evaluation software is
needed to control various aspects of each part. This software can
be found on the respective product web pages under the Tools,
Software, & Simulations Models link.
Collect the evaluation boards and connect all the signal paths
together, as shown in Figure 7. Connect all boards to +5 V and
the two AD8130 boards to −5 V as well. Ensure that the power
supply current is consistent with what is expected.
As shown in Figure 7, make the following connections:
Once the software is downloaded and installed, plug in the USB
cables from the computer to the evaluation boards and then run
the software for the part that needs to be controlled.
Functional Block Diagram
Figure 7 shows the functional block diagram of the test setup that
was used for testing the receive chain. The ADL5336 evaluation
board only allows for single-ended input and output. The same
is true for the RF input on the ADL5387 board. The RF output
port on the vector signal generator is only single ended; therefore, a
balun between the generator and the input of the ADL5336 is
necessary. As shown in Figure 7, the rest of the signal path is
differential until the AD8130 difference amplifiers. The differential-
to-signal-ended conversion was needed because the oscilloscope
only allows for sampling of single-ended signals while being
controlled by the VSA software.
Setup and Test
The first step of the setup of the receiver test is to turn on all test
equipment. While the test equipment is warming up, the boards
must be configured correctly for proper use in this signal chain.
On the ADL5336, ensure that the 0 Ω jumper resistors that connect
the VGA1 output to the VGA2 input are populated
On the ADL5387 board, bypass the output baluns for full differential,
dc-coupled signal paths between the ADL5387 and the ADRF6510.
On the ADRF6510 board, do the following:
• Bypass the input and output baluns
• Place 1 kΩ differential output loads on the output signal
lines (two 500 Ω resistors to ground will suffice on each
output path)
• Replace the stock COFS capacitors with 1 µF capacitors
• Connect the single-ended, 50 Ω output of the vector signal
generator to INPUT1 of the ADL5336 evaluation board.
• Connect the I signal path output of the AD8130 to Input 1
on the oscilloscope, and connect the Q signal path output
of the AD8130 to Input 3 of the oscilloscope.
• Connect the USB cable from the PC to the oscilloscope.
• Connect the RF port of the signal generator to the LO
input of the ADL5387 evaluation board.
On the Agilent E4438C signal generator, do the following:
• Set the frequency to 400 MHz
• Set the amplitude to 0 dBm
• Turn the RF port on
On the Agilent E4438C vector signal generator, do the following:
• Set the RF carrier frequency to 200 MHz
• Set the amplitude to −30 dBm
• Turn the RF port on
• Turn on the custom ARB inside the vector signal generator
• Set the signal to 4-QAM, symbol rate to 5 MSPS, and pulse
shaping filter alpha to 0.35
On the PC, start the Agilent 89600 VSA software. In the VSA
software, do the following:
• Turn the digital demodulator on
• Set the input to the I+ jQ option
• Set the frequency to 0 Hz, symbol rate to 5 MSPS, and
alpha to 0.35
ADL5336
EVALUATION BOARD
ADL5387
EVALUATION BOARD
ADL5387-EVALZ
ADL5387
ADRF6510
AD8130
EVALUTION BOARD EVALUTION BOARDS
ADRF6510
AD8130-EBZ
AGILENT E4438C
VECTOR SIGNAL
GENERATOR
ADL5336-EVALZ _ADL5336
0°
DIV BY 2
90°
I
2xLO
AD8130-EBZ
Q
ADRF6510-EVALZ
POWER SUPPLIES
+5V TO ALL BOARDS
GND TO ALL BOARDS
–5V TO AD8130 BOARDS
AGILENT E4438C
SIGNAL
GENERATOR
COMPUTER
AGILENT 89600
VSA SOFTWARE
USB
Figure 7. Functional Block Diagram for Testing Direct Conversion Receiver
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