The AS5900 device is a low noise, 128-channel current-to-digital converter that enables the readout of the photodiodes with highest sensitivity. High-resolution CT imaging can be achieved up to 26-bits resolution. Its 128-low-noise and high linear converter channels provide an increased gray scale, improved contrast and reduce artifacts of 3D CT images. The low power consumption of 1mW per channel reduces self-heating effects and the overall power consumption of the system. An integrated temperature sensor allows the calibration of temperature drifts of the X-ray detector modules.