  We report on the development of an innovative CdTe detector plane (DPIX)
optimized for the detection and localization of gamma-ray bursts in the X-ray
band (below 100 keV). DPIX is part of an R&D program funded by the French Space
Agency (CNES). DPIX builds upon the heritage of the ISGRI instrument, currently
operating with great success on the ESA INTEGRAL mission. DPIX is an assembly
of 200 elementary modules (XRDPIX) equipped with 32 CdTe Schottky detectors
(4x4 mm2, 1 mm thickness) produced by ACRORAD Co. LTD. in Japan. These
detectors offer good energy response up to 100 keV. Each XRDPIX is readout by
the very low noise front-end electronics chip IDeF-X, currently under
development at CEA/DSM/DAPNIA. In this paper, we describe the design of XRDPIX,
the main features of the IDeF-X chip, and will present preliminary results of
the reading out of one CdTe Schottky detector by the IDeF-X V1.0 chip. A
low-energy threshold around 2.7 keV has been measured. This is to be compared
with the 12-15 keV threshold of the ISGRI-INTEGRAL and BAT-SWIFT instruments,
which both use similar detector material.
