“Evaluation of the X-ray SOI pixel detector with the on-chip ADC”, authored by Mr. Matsuhashi (M2, Bamba Lab.), has been accepted for publication in NIMA. In this paper, we evaluated the performance of XRPIX, an X-ray detector for space X-ray observation, with a built-in high-speed AD converter that converts analog signals to digital signals in about 6 μs. As a result, it was proved that the AD converter works properly and that the detector can be digitized as required when mounted on an astronomical satellite and that it performs well enough to observe astronomical objects. For more information, please click here.