\begin{center}
\begin{circuitikz}[scale=0.8] \draw
    % Upper line
    (0,2) node [anchor=east] {$U_{B}$}
    to [short, l=+, o-*] (1,2)
    to [R=210\ohm,*-*] (4,2)
    to [R=100\ohm,*-*] (7,2)
    to [R=10\kilo\ohm,*-*] (10,2)
    (13,2) to [D, l_=SiPM,*-*] (10,2)
    (13,2) to [C=100\nano\farad,*-o] (15,2) node [anchor=west] {Signal}
    % Connection to the ground line
    (1,2) to [C=100\nano \farad, *-*] (1,0)
    (4,2) to [C=100\nano \farad, *-*] (4,0)
    (7,2) to [C=100\nano \farad, *-*] (7,0)
    (10,2) to [C=100\nano \farad, *-*] (10,0)
    (13,2) to [R=50\ohm, *-*] (13,0)
    % Ground line
    (0,0) node [ground, rotate=-90] {} -- (15,0) node [ground, rotate=90] {};
    % Draw a dotted line to separate pi filter and hamamatsu circuit
    \draw[dashed, red] (7.6,-1) -- (7.6,5);
    \draw (4,4) node {Pi Filter};
    \draw (11,4) node {\textsc{Hamamatsu} Circuit};
\end{circuitikz}
\end{center}