\begin{itemize}
\item Been done before, but not as a Libre Design.
- \vspace{4pt}
+ \item Sanjay Charagulla: GlobalFoundries, 22nm mobile process
+ can reach as low as 0.4v
\item GPIO Banks need per-bank VREF (1.8v? to 3.3v)\\
IO pads need built-in
level-shifting to convert to CPU VCORE
- \vspace{4pt}
\item Each core needs independent variable-voltage capability
and independent shut-down (PMIC supplies external voltage)
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\item DDR RAM still needs refreshing (even in sleep mode)
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\item Extra RV32 (PicoRV32?) always-on core for wake-up / RTC?
- \vspace{4pt}
\item PLLs are Analog. fun fun fun in the sun sun sun...
\end{itemize}
{\it Really need help here. PLLs, Analog stuff: very specific