Say that a president faces multiple charges after being impeached by the US House, and that the Senate vote on conviction has 2/3rds or more of the Senate voting to convict the president on at least 1 charge, but no single charge has 2/3rds or more of the Senate voting to convict.
So when a jury votes by charges, it is only on that charge. So you would need to reach the threshold (2/3ds) to be guilty of that specific charge. If you don't reach the threshold, you're acquitted.
In the military, we have non-unanimous verdicts and we break it out by charges and specifications.
E.g.:
CHARGE I - Violation of Art. 112a - Uniform Code of Military Justice (UCMJ)
Specification - We'd explain the specific offense here as to how the person violated the specific article of the UCMJ.
CHARGE II - Violation of Art. 113 - UCMJ
Specification - Insert spec.
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If a jury only reaches the threshold for CHARGE I but not CHARGE II, then the person is only guilty of CHARGE I.
For multi-specification charges (cause you may be breaking an Article in numerous ways), the same principles apply. You have to be found guilty on each specification.
If you are not found guilty of at least one specification of the charge, you are found not guilty on the charge.
