How do you properly ground the eval board for HMC487LP5E?
The answer to your question is not obvious from the eval board drawing shown on the data sheet.
To obtain an answer, I used a Gerber viewer to view the board files.
From those files I was able to determine that the DC header pins highlighted in yellow below connect to the board ground.
Thank you. Do all of these pins need to be connected to ground?
You're welcome, I'm glad to help.
The J3 and J4 pins highlighted in yellow all connect to the PCB ground and are thus all DC common with one another. You will need to connect your Vgg and Vdd DC supply grounds to the board ground via at least one of the yellow pins, but you don't need to connect the DC supply grounds to ALL of the J3 and J4 (yellow) ground pins. However, considering the high quiescent Idd=1300 mA, for the Vdd connections I recommend that your use wires of heavy enough gauge to minimize the V=IR drop between the Vdd supply outputs and the PCB. This recommendation applies to both the Vdd supply output as well as its ground/return. For the same reason I also recommend that you connect the Vdd supply ground to more than one of the yellow ground pins.
Let me know if you have additional questions.
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