A charge processing circuit which integrates charge at an output node that is representative of an input charge provided at an input node. The circuit includes a precharge path coupled to the input node, the precharge path operable for setting the potential of the input node to a fixed precharge potential prior to introduction of input charge to the input node. A sensing path is coupled to the input and output nodes which is operable for returning the potential of the input node to the fixed precharge potential subsequent to introduction of input charge to the input node. A feedback element has an input coupled to the sensing path and the precharge path, the feedback element operable for setting said fixed precharge potential. In another embodiment there is provided a method of integrating charge at an output node of a charge processing circuit that is representative of input charge provided at an input node. The method includes replenishing charge at the input node; draining charge from the input node; stopping the draining of charge from the input node in response to a feedback element detecting when the input node reaches a fixed precharge potential; introducing an input charge on the input node from a source; draining charge from the input node onto the output node; and stopping the draining of charge from the input node in response to a feedback element detecting when the input node reaches the fixed precharge potential.