PH pins (10,13,14,15,16,17,18,19,42) – according to the datasheet shouldn't be connected to anything and stay floating. When I look at the EVB it seems you connected it to AGND through a resistor. The EVB indicate do not assemble the resistor
AGND pins (2,23) – according to the datasheet shouldn't be connected to anything and stay floating. When I look at the EVB it seems you connected it to PGND through a resistor. The EVB indicate do not assemble the resistor
So, do I really need these resistors in my layout? Can I remove them?
The layout consideration doesn't show how to connect between the copper plane of PH and AGND through resistor, and also doesn't show how to connect the PGND and AGND through a resistor (page 26 in datasheet). Can you provide the layout of the EVB board?
In reply to meital rave:
The schematic for the LMZ31710 EVM shows a test point on the PH node and a test point for AGND. These would be used for monitoring the PH for switching frequency. These test points are NOT recommended to be added your layout.
The resistor (R15) shown in the schematic is not required on your layout. The PGND to AGND connection is made internal to the LMZ31710 device.
In reply to J Arrigo:
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