Rapid development in CMOS technology has resulted in its suitability for the implementation of readout front-end systems in terms of high integration density, and low power consumption yet at the same time posing many challenges for analog circuits design like readout front-end. One of the significant challenges is the low noise design for high speed front-end systems, while at the same time minimizing the power consumption as much as possible.A high speed, low noise, low power, and programmable readout front-end system is designed and implemented for an X-ray detector in CMOS 0.18 m technology in this work. The material in this book is for both professionals in Analog IC Design and students; graduate as well as senior year undergraduate.