Patent ID: 8260565

Claim:
An electronic circuit adapted to be used in radiation sensing comprising: a charge amplifier, including a operational amplifier and a first capacitor electrically connected in parallel and having a common input node connected to an anode of the operational amplifier and a common output node connected to a cathode of the operational amplifier, receiving a total quantity of charge at the common input node from a radiation detector and generating a voltage output at the common output node; at least one switch including a switch output node and a switchable input node, wherein the switchable input node of the at least one switch is configured to be connected to a first voltage of at least two voltages; at least one second capacitor electrically connected in series between the common input node and the switch output node, the at least one second capacitor being electrically connected to the common input node without a switch connected therebetween; a comparator including a first input node, a second input node; and a comparator output node, wherein the first input node is electrically connected to the common output node and the second input node is electrically connected to a threshold voltage, wherein the comparator makes a comparison of the voltage output generated at the common output node and the threshold voltage and delivers a result of the comparison to the comparator output node; a logic circuit electrically connected to the comparator output node and to the at least one switch and controlling selective coupling of the switchable input node based upon the result delivered to the comparator output node, wherein if the result delivered to the comparator output node indicates that the voltage output does not equal or exceed the threshold voltage, then the logic circuit leaves the configuration of the at least one switch as it is, else wherein if the result delivered to the comparator output node indicates that the voltage output is equal to or exceeds the threshold voltage, then the logic circuit selects a second voltage of the at least two voltages for coupling to the switchable input node of a first of the at least one switches appropriate to activate a first of the at least one second capacitors and to effect a subtraction of some quantity of charge from the total quantity of charge received at the common input node from the rediation detector; and an analog signal processing circuit electrically connected to the common output node and providing analog filtering of the voltage output generated by the charge amplifier.