The Solar X-ray Detector (SXD), developed by Beijing Institute of Control Engineering, aims to observe solar X-ray radiation data of different intensity classes to reveal the distribution law of the magnetic field in the low Earth orbit, as well as the coupling law of the Earth magnetic field, the solar radiation and energy particle distribution.

This instrument consists of two soft X-ray detection units (SXDU1 and SXDU2) and two hard X-ray detection units (HXDU1 and HXDU2), covering wide energy range of 1-600keV. The SXDUs can work in the spectrum mode and the counting mode and The HXDUs only work in the counting mode. Each of the four detection units is equipped with a collimator to define the field of view, block the stray light and limit the effective detection area.