Measurement of ionizing particles by the PH32 chip

The PH32 readout chip for the measurement of X-rays, beta radiation and ions including alpha particles has been developed recently. The chip was manufactured using a commercial 180 nm CMOS process and can be used in the dose rate measurement and the basic spectroscopy. It is able to measure generated charge as well as counting hits from a silicon sensor in two operation modes. The low range mode is able to measure generated charge in the range from 7 ke^- to 40 ke^- for soft X-rays and beta radiation, the high range mode in the range from 200 ke^- to 5 Me^- for alpha particles. The measurement accuracy is about 1700 e^- for the chip calibration charge of 16 ke^- and 37 ke^- for the calibration charge of 3 Me^-. The measurements presented in this paper are focused on the channel response to the injected charge including linearity, gain, channel uniformity, noise and dispersion. The energetic spectrum of ²⁴¹ Am and ²³⁹Pu is presented together with the ability to measure the dose rate in the range of 8-orders of magnitude.