Power Architecture Review
V5 buck output is directly tied to U1:5V, and the RP2040 Zero’s 5 V/VUSB/VSYS node is directly connected internally, so the fix should split V5 into buck-side and RP2040-side rails with a Schottky/ideal-diode power path; I also flagged Q1 source/drain orientation and C11’s likely net/role mismatch.
ryanf