Development of front-end electronics for the luminosity detector at ILC

The design and measurements of the prototype front-end electronics for the luminosity detector (LumiCal) at the International Linear Collider (ILC) are presented. The challenges of the LumiCal front-end electronics are discussed and the proposed architecture comprising switched-gain preamplifier, pole-zero cancellation circuit (PZC) and switched-gain shaper is described. The preamplifier works for a wide range of input capacitance of up to 100pF. The input charge dynamic range extends from <0.4fC to >10pC and covers more than four orders of magnitude. To conform with the timing requirements a peaking time (Tpeak) of about 70ns was chosen. The prototype ASIC comprising eight channels was designed and fabricated in 0.35μm CMOS technology. The results of measurements on gain, noise, high count rate performance and crosstalk are presented.