Joint progresses in Cd(Zn)Te detectors, microelectronics and interconnection
technologies open the way for a new generation of instruments for physics
and astrophysics applications in the energy range from 1 to 1000 keV. Even
working between –20 and 20°C, these instruments will offer high spatial
resolution (pixel size ranging from 300 300 µm² to few mm²),
high spectral response and high detection efficiency. To reach these goals,
reliable, highly integrated, low noise and low power consumption electronics
is mandatory. Our group is currently developing a new ASIC detector front-end
named IDeF-X, for modular spectro-imaging system based on the use of Cd(Zn)Te
detectors. We present the most recent version of IDeF-X which is a sixteen channels
analogue readout chip intended for use with low capacitive detectors. It has been
processed with the standard AMS 0.35 µm CMOS technology. Each channel consist
of a CSA, a pole zero cancellation stage, a variable peaking time Sallen & Key type
filter and an output buffer. The CSA is designed to be DC coupled to detectors having
a low dark current at room temperature and the compensation stage is continuously self
adapted to this dark current. |
