ANDESPix is a digital silicon photomultiplier (SiPM) ASIC designed to readout scintillating
fibers with low light intensity, as part of a muon detector, following the same muon detection
principle used for muon detectors at the Pierre Auger Observatory. Thereby, photons should
be detected with very high time resolution (<100 ps) in order to identify impinging muons and
their time of arrival (ToA) on the muon detector. In ANDESPix, each single photon avalanche
diode (SPAD) has its own digital readout containing a time-to-digital converter (TDC). The zerosuppressed
digital readout allows to receive detailed spatial information of incoming photons.
This may lead to better understanding of their nature and increased detector efficiency, as e.g.
improved fiber alignment to the SiPM and improved detection of the impinging position along the
scintillator bars of the muon detector. ANDESPix is designed in 110 nm CMOS technology from
LFoundry (LF11IS). This technology includes a SPAD cell for the wavelength range from 400 nm
to 850 nm with high photon detection efficiency (PDE) and low dark count rate (DCR) developed
by Fondazione Bruno Kessler (FBK). First measurement results are presented at the symposium.