Quick Start
5
Quick Start
This section assumes all engineering knowledge on the device and basic overview of the VCA5807EVM.
5.1
Test Setup
Connect the EVM as shown in . Typical input signals are 5 MHz at –32 dBm. This can be applied to any
VCA input (J1-J8). If the signal is noisy, consider using a 5-MHz filter. Connect a scope or a spectrum
analyzer to the corresponding VCA output in order to measure the gain on the channel.
5.2
Power Up VCA5807EVM
Connect ±5-V power to the board. No other power connection is needed.
5.3
Launch the VCA5807 GUI
Launch the VCA5807EVM GUI. Execute a software reset with the GUI and verify the current consumption
drops from
≈
0.762 A to
≈
0.646 A. Enable the Active Termination Resistor of 50 Ohms (check the box) on
the LNA+VCA+PGA+LPF tab. This tab is also used to vary the gain on each channel. However, with the
default settings as shown in , the gain should be 42 dB overall. Therefore, with an input signal of 5 MHz at
–32 dBm, load resistance of 50
Ω
, and an overall gain of 42 dB, the output should read
≈
4 dBm or 1 Vpp.
For more details and other modes for testing and evaluating the VCA5807 device, please refer to the
previous pages of this development guide.
17
SLOU352 – November 2012
VCA5807 Development Guide
Copyright © 2012, Texas Instruments Incorporated
