Using the EVM in CW Mode
17
SLOU489 – August 2017
Copyright © 2017, Texas Instruments Incorporated
AFE5832 32-Channel Analog Front-End Evaluation Module (EVM Rev. A)
6
Using the EVM in CW Mode
Demonstrating the CW mixer in the AFE is done by following these steps:
1. In the AFE5832 GUI, reset and initialize the device by referring to
and
. Remember
to connect a –5-V and a 5-V source to the device.
2. Connect a sine wave generator to any SMA channel. Set the frequency to 1.963125 MHz and the
amplitude to –23 dBm.
3. Provide a 125-MHz, +10-dBm clock input to J56 of the AFE EVM (LMK external clock). Refer to
for jumper configurations.
4. Turn
Switch 4
contained in
S5
on the AFE EVM to 'on'. The red LED, D8 should not light up. For more
information on the CPLD, refer to
.
5. Connect two cables to an oscilloscope with timebase of 40 µs and 500 mV / div. Input resistance
should be 1 M
Ω
on each scope channel. DC couple the oscilloscope.
6. Connect those two cables to SMAs, J66 and J68 on the AFE EVM.
7. Choose the following data format on the AFE5832 EVM GUI:
Figure 20. CW Mode Preset
8. Trigger the oscilloscope on either channel.
9. The oscilloscope displays the frequency I and Q signals at 10 kHz as shown in
. The
amplitude should be around 1.5 Vpp ±300 mVpp, though this amplitude may change. The frequency
should be 10 kHz and the I and Q signals should be 90 degrees out of phase.