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Noise Studies on APD and Crystal s. We connected to a CV meter and to the test board for FPPA:. APD. APD+CRYSTALS. Capacitors. The goal is to see how different from a pure capacitors the APD or APD+CRYSTALS systems are. SET-UP. Capacitance measurements. The APD and APD+CRYSTAL
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Noise Studies on APD and Crystals We connected to a CV meter and to the test board for FPPA: APD APD+CRYSTALS Capacitors The goal is to see how different from a pure capacitors the APD or APD+CRYSTALS systems are.
Capacitance measurements The APD and APD+CRYSTAL systems are identical, with a capacitance at full depletion of 165-170 pF
Noise Measurements We studied the noise induced by the APD or APD+CRYSTALS as a function of the bias voltage. This noise is due to their capacitance plus some extra component... Values for a pure capacitor: 598pF --> 1.2 mV 168pF --> 0.9 mV 0 pF --> 0.5 mV 168 pF 550pF
Comments - The noise generated by an APD is almost identical to what is induced by an equivalent capacitor. - The noise induced by the APD+CRYSTAL is very dependent upon the conditions used (wrapping, no wrapping, ground, shields..) In the best case it was a 20-30% higher than a pure APD. - We need to study more realistics set-ups. ALVEOLA+....