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Daughter boards
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SDRAM XSDS v2.9 decoupling issues #17

Closed prrole closed 1 year ago

prrole commented 3 years ago

Pin 37 CKE is decoupled, while pin 1&3 VCC share a capacitor. I assume this is a routing mistake as all 3 pins are labeled VCC.

74LVC1G04 could probably benefit from a decoupling capacitor as well.

sorgelig commented 3 years ago

pins 1&3 are very close to each other and have large polygon connected to both, so i don't think there will be any noticeable benefit for that. Pin 37 has capacitor not as CKE but as distributed capacitance since it's far from other capacitors. For LVC1G04 - probably can connect its VCC to upper polygon and share the cap nearby. I will think about it if i will update the design