Mixed Mode Radiation Event Detector
A reversed biased PIN diode acts as a radiation event detector, sensing the occurrence of an ionizing radiation pulse, which is connected to a threshold detector, the resistor RThreshold, that drives the base input of a complementary (Q1 and Q2) pulse amplifier. The output of the amplifier is supplied to the base of Q4 that drives a pulse circuit (Q5 and Q6) with a time constant set by RT x CT. The Radiation Event Detector circuit is shown in Figure 1.