Part Number: LMX2820EVM
Other Parts Discussed in Thread: LMX2820, USB2ANY
Hi Team, seeking your assistance.
possible solutions to get our LMX2820EVM working according to the EVM Quick Start procedure described in the TICS Pro and documentation for this device, I am reaching you to confirm or disprove my approach.
Before I followed the procedure EVM Quick Start procedure, in TICS Pro, I selected the target device under "Select Device" -> "PLL + VCO" -> "LMX2820".
Then I read the **Readme** section and followed the procedure described in the "EVM Quick Start" in the left bar.
In step 1: I applied 3.3 V to the + and - headers. I measured the DC voltage on the TP_VDD and TP_GND pins, which was 1.4 V. (FYI, no LED lighted on the board)
In step 2: I used TI LMK61PDOA2 Reference PRO board for the 100 MHz reference clock. I confirmed that the single-ended output had 100 MHz, 0.8 Vpp on 50 Ohms, on our oscilloscope. (FYI, the Reference PRO was connected to a different device than my PC to get power from. The Reference PRO was configured to output 100 MHz LVPECL signal, while the unused pin was terminated with a 50 Ohm terminator)
In step 2: I also used our arbitrary function generator as the 100 MHz reference clock (I tried both Sine and Square functions). I also confirmed that the single-ended output had 100 MHz, 0.8 Vpp on 50 Ohms, on our oscilloscope. I also tried to vary the output voltage within the V_OSCin min and max range, as stated in the documentation.
In step 3: I used a 50 Ohm terminator on RFOUTP and connected RFOUTN to the oscilloscope. I tried two different coaxial cables in case the losses would be too significant. Here, the losses were around 1.3 V and 1.6 V.
In step 4: I connected the ribbon cable to the USB2ANY, as shown in the picture. The firmware of the USB2ANY has already been upgraded before.
In step 5: I clicked on the "EVM Default Mode" under "Default Configuration" in the top menu.
In step 6: I selected "Write All Registers" in the "USB communications" in the top menu.
Modifications: After that, to ensure that the output frequency matches the frequency range of our oscilloscope, I set the output frequency in the "RFOUTA" box to 100 MHz in the PLL section, hit enter and Ctrl + L.
Verifications: According to the Troubleshooting Guide, I went to "USB Communications" -> "Interface" -> Clicked "Identify" -> Verified that the USB2ANY LED was blinking.
Thank you.
-Mark
