VDDA Voltage & 12Gbps

Digging through the documentation for the PolarFire, it appears the transceiver lane supply voltage (VDDA) needs to be 1.05V[1] to allow for rates above 10.3125 Gbps. If I’m reading the BeagleV-Fire schematic correctly, the MCP1725 LDO generating the VCCA_1V0 signal feeding the FPGA VDDA rail is set for a 1.025 typical output voltage[2]. Is it expected that the transceivers will operate at rates above the 10.3125Gbps? I suspect everything will “JustWork” ™, but I’m new to the PolarFire and am wondering about the design choices.

[1] Rates below 10.3125Gbps, VDDA = 0.97V min / 1.00V typ / 1.03V max
With any transceiver running above 10.3125Gbps, VDDA = 1.02V min / 1.05V typ / 1.08V max

[2] With the 15K/10K feedback network and the MCP1725 0.410 typ. adjustment reference voltage, VOUT is 0.41 * ( (15K + 10K) / 10K ) = 0.41 * 2.5 = 1.025V typ (excluding resistor and VADJ tolerance).

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Number [2] is nice.

Thank you. I appreciate the feedback in math equations (at times). I am sure it gets more complicated than I am aware of currently but…

  1. Good, ole programming math rules.
  2. Hopefully, [1] is correct.

I purchased one of these boards to test FPGA w/ specific source, Linux, and to follow along as best I can during intervals.

Anyway…just a shouting match here for math.