\documentclass[border=0mm]{standalone}

\usepackage{cmap}
\usepackage[cp1250]{inputenc}	
\usepackage[T1]{fontenc}
\usepackage{graphicx}
\usepackage{lmodern}
\usepackage{tikz}
\usepackage{float}
\usepackage{siunitx}
\usepackage{amsmath}
\usepackage{upgreek}
\usepackage{pgfplots}
\pgfplotsset{compat=1.17}
\usepgfplotslibrary{fillbetween}
\usepgfplotslibrary{units}
% \makeatletter
%\pgfplotsset{
%  unit code/.code 2 args=
%    \begingroup
%    \protected@edef\x{\endgroup\si{#2}}\x
%} 
%\makeatother

\pgfkeys{%
  /tikz/on layer/.code={
    \pgfonlayer{#1}\begingroup
    \aftergroup\endpgfonlayer
    \aftergroup\endgroup
  }
}

\begin{document}
	\begin{tikzpicture}
		\begin{axis}[
			height=7cm,	width=11cm,	grid=major,
    		x unit=\SI{}{\micro\ampere}, y unit=\SI{}{\mega\hertz},
			xlabel=$I_\mathrm{BIAS}$,	ylabel=$f_\mathrm{0}$,
			ymin=0,ymax=1250,
			xmin=5, xmax=30,
			ytick = {0,250,500,625,750,1000,1250},
			xtick ={5,10,15,20,25,30},
			set layers,
			y tick label style={/pgf/number format/.cd, set thousands separator={}},
			xticklabel shift = 2 pt,
			legend pos=north west
		]					
			
			\addplot +[solid, smooth, thick,color=blue,mark=none] table [x expr=\thisrow{nomx}*1e6, y expr=\thisrow{nomy}*1e-6, col sep=semicolon] {../cadence_data/ccdlu_f0.csv};
			\addlegendentry{nominal};
			%\addplot +[solid, smooth, thick,color=red,mark=none] table [x expr=\thisrow{x1}*1e6, y expr=\thisrow{y1}*1e-6, col sep=semicolon] {../cadence_data/ccdlu_f0.csv};
			\addplot +[solid, smooth, thick,color=red,mark=none] table [x expr=\thisrow{x2}*1e6, y expr=\thisrow{y2}*1e-6, col sep=semicolon] {../cadence_data/ccdlu_f0.csv};
			\addlegendentry{SS, hot, low $V_\mathrm{DD}$};
			%\addplot +[solid, smooth, thick,color=red,mark=none] table [x expr=\thisrow{x3}*1e6, y expr=\thisrow{y3}*1e-6, col sep=semicolon] {../cadence_data/ccdlu_f0.csv};
			%\addplot +[solid, smooth, thick,color=black,mark=none] table [x expr=\thisrow{x4}*1e6, y expr=\thisrow{y4}*1e-6, col sep=semicolon] {../cadence_data/ccdlu_f0.csv};
			%\addplot +[solid, smooth, thick,color=black,mark=none] table [x expr=\thisrow{x5}*1e6, y expr=\thisrow{y5}*1e-6, col sep=semicolon] {../cadence_data/ccdlu_f0.csv};
			%\addplot +[solid, smooth, thick,color=red,mark=none] table [x expr=\thisrow{x6}*1e6, y expr=\thisrow{y6}*1e-6, col sep=semicolon] {../cadence_data/ccdlu_f0.csv};
			\addplot +[name path = FF, solid, smooth, thick,color=blue, draw=none,mark=none] table [x expr=\thisrow{x1}*1e6, y expr=\thisrow{max}*1e-6, col sep=semicolon] {../cadence_data/ccdlu_f0.csv};
			\addplot +[name path = SS, solid, smooth, thick,color=blue,draw=none,mark=none] table [x expr=\thisrow{x1}*1e6, y expr=\thisrow{min}*1e-6, col sep=semicolon] {../cadence_data/ccdlu_f0.csv};	
			\addplot[blue, fill opacity = 0.15] fill between[of=SS and FF];
			\draw [-,dashed] (axis cs:16.22,0) -- (axis cs:16.22,625) ;
			\node [] at (axis cs:18.2,100) {$\SI{16.22}{\micro\ampere}$};
			
		\end{axis}
	\end{tikzpicture}
\end{document}