Patent ID: 7023373

Claim:
An analog/digital converter for converting an analog input signal into a digital value, comprising: a first converter stage comprising an input and a signal output, the first converter stage further comprising: a comparison circuit configured to compare a signal amplitude of a signal applied to the input of the first converter stage with amplitudes of at least two reference signal elements, and configured to output a first control signal to a control output of the first converter stage in response thereto; a generator circuit configured to output a signal derived from a level of the signal applied to an input thereof to an output of the generator circuit of the first converter stage; a second converter stage connected downstream of the first converter stage, the second converter stage comprising: a control input configured to receive the first control signal, the control input connected to the control output of the first converter stage; a signal input connected to the signal output of the first converter stage; a signal output; a comparison circuit configured to compare a signal amplitude for an input signal applied to the input of the second converter stage with amplitudes of two reference signals, and configured to output a second control signal to a control output of the second converter stage, wherein the amplitudes of the two reference signals in the second converter stage are determined by the first control signal at the control input; and a generator circuit configured to output an output signal derived from a level of the input signal at the input and from the first control signal at the control input to an output of the generator circuit of the second converter stage; an evaluation circuit connected to the control outputs of the first and second converter stages, respectively, and configured to ascertain a digital value from the first and second control signals; and an amplification device comprising an input coupled via a first switching device in a first switching state to the output of the generator circuit in the first converter stage and in a second switching state to the output of the generator circuit in the second converter stage, comprising an output coupled to the signal output of the first converter stage and to the signal output of the second converter stage.