# USB bus power destroys MCU PA07 ## Problem environment The electrical area above the ball at F3 (bottom left corner corresponding with PA07) is smoke burned and destroyed when 5V bus power is present. ## Steps to reproduce 1. Observe the area above ball F3 1. Insert a powered USB cable in J2 ## Expected result Part of the MCU should not be destroyed when bus power is applied. ## Actual result Part of the MCU is destroyed and magic smoke escapes. ## Workaround Cut the trace from C5 to PA07. ## Severity level This is **high priority** because circuit damage is imminent.

Resolved by 95df659.