\documentclass[12pt,border=1pt,crop,multi=false,tikz,class=scrartcl]{standalone}
\usepackage[T1]{fontenc}
\usepackage[utf8]{inputenc}
\usepackage{lmodern}
\usepackage[american]{circuitikz}
\usetikzlibrary{calc,positioning}
\renewcommand*{\familydefault}{\sfdefault}
\begin{document}
\begin{circuitikz}[american]
\draw [semithick,scale=1.25]
(0,0) node [left] {V\textsubscript{in}} to [short,o-*] ++(1.5,0) |- ++(2,-1) node [pnp=T3,anchor=B] (t3) {} node [right=8mm] {T3}
(1.5,0) |- ++(2,1) node [npn,anchor=B] (t1) {} node [right=8mm] {T1}
(t3.E) to [short] (t1.E)
($(t1.E)!.5!(t3.E)$) node (n1) {} to [short,*-o] ++(2,0) node [right] {V\textsubscript{out}}
(n1) to [short,-*] ++(-2,0) -- ++(0,1) to [empty diode,l=D1,-*] ++(0,2) -- ($(1.5,0)+(2,3)$) node [npn,anchor=B] (t2) {} node [right=8mm] {T2}
(t2.E) to [short] (t1.C)
($(n1)-(2,-3)$) to [R=R1] ++(0,2) to [short,-o] ++(4,0) node [right] {$+$80V}
(t2.C) to [short,-*] ($(n1)+(0,5)$)
($(n1)-(2,3)$) to [empty diode,l=D3,*-] ++(0,2) -- ++(0,1)
($(n1)-(2,3)$) -- ($(1.5,0)+(2,-3)$) node [pnp,anchor=B] (t4) {} node [right=8mm] {T4}
(t4.E) to [short] (t3.C)
($(n1)-(2,3)$) to [R=R2] ++(0,-2) to [short,-o] ++(4,0) node [right] {$-$80V}
(t4.C) to [short,-*] ($(n1)-(0,5)$)
($(t2.E)!.5!(t1.C)+(2,0)$) node [right] {$+$40V} to [empty diode,l_=D2,o-*] ++(-2,0)
($(t3.C)!.5!(t4.E)$) to [empty diode,l_=D4,*-o] ++(2,0) node [right] {$-$40V}
;
\end{circuitikz}
\end{document}