Transconductance calibration of n-XYTER 1.0 readout ASIC

After an overview of n-XYTER 1.0—a high-gain, charge-sensitive, self-triggering readout ASIC—the experimental work on its transconductance calibration is presented in details. Reference charge pulses were generated by applying a voltage step over a capacitor. Special care was taken to achieve the best possible precision and to check for potential systematic errors. The calibration was done on 3 chips and many channels. Average calibration curves were determined for both positive and negative polarities and the uncertainties were estimated. Finally, correctness of the calibration was confirmed by a measurement with an alternative signal source—a silicon detector, exposed to γ-radiation of 241Am.