We present the design and test results of a high-speed low-noise front-end readout Application Specific Integrated Circuit (ASIC) prototype, which is designed for a novel ionization chamber of the high intensity beam detection. This ASIC prototype is a single-channel ASIC and composed of a charge collection electrode, a Charge Sensitive Amplifier (CSA), a discriminator, a buffer and a two-stage source follower. Three different feedback capacitances are implemented in the CSA. The prototype has been manufactured in a standard 0.18μm CMOS proces...