A fast, compact solution for low noise charge preamplifiers

A new structure for low noise charge sensitive preamplifiers, implemented using a transconductance gain stage plus a voltage gain stage, has been thoroughly investigated. Uniquely high values of open-loop gain have been demonstrated, together with good low noise performance and high load driving capability. Implementation of this scheme uses only a minimal number of commercial parts, resulting in a very compact and relatively low power circuit. A detailed theoretical analysis of the dynamic response and noise performance of the circuit is given. Several tests and measurements have been performed to validate the theory and the results are presented.