An electric circuit for operating a ratiometric sensor which is adapted to generate a ratiometric sensor signal (26, 26') on the basis of a detected measurement parameter and which has an allowable operation voltage range outside of which the sensor signal (26, 26') is no longer ratiometric, comprising: an operation voltage amplifier which has an input for receiving a supply voltage from a voltage source, wherein the operation voltage amplifier is adapted to generate an operation voltage for the sensor from the supply voltage provided by the voltage source, wherein the ratio of the operation voltage to the supply voltage is determined by a settable voltage amplification factor; at least one signal amplifier (28, 28') which has an input for receiving the ratiometric sensor signal (26, 26') from the sensor and an output (O1, 02) for outputting an output signal (30, 30'), wherein the signal amplifier (28, 28') is adapted to generate the output signal (30, 30') from the ratiometric sensor signal (26, 26'), wherein the ratio of the output signal (30, 30') to the ratiometric sensor signal (26, 26') is determined by a settable signal amplification factor; and a control unit which likewise has an input for receiving the supply voltage from the voltage source, wherein the control unit is adapted to generate at least one control signal (18, 20) for setting the voltage amplification factor and the signal amplification factor in dependence on the supply voltage; wherein the voltage amplification factor is inversely proportional to the signal amplification factor; and wherein the control unit is adapted to reduce the voltage amplification factor so far that the operation voltage provided by the operation voltage amplifier lies within the allowable operation voltage range when the supply voltage exceeds a maximum allowable operation voltage of the ratiometric sensor. an operation voltage amplifier which has an input for receiving a supply voltage from a voltage source, wherein the operation voltage amplifier is adapted to generate an operation voltage for the sensor from the supply voltage provided by the voltage source, wherein the ratio of the operation voltage to the supply voltage is determined by a settable voltage amplification factor; at least one signal amplifier (28, 28') which has an input for receiving the ratiometric sensor signal (26, 26') from the sensor and an output (O1, 02) for outputting an output signal (30, 30'), wherein the signal amplifier (28, 28') is adapted to generate the output signal (30, 30') from the ratiometric sensor signal (26, 26'), wherein the ratio of the output signal (30, 30') to the ratiometric sensor signal (26, 26') is determined by a settable signal amplification factor; and a control unit which likewise has an input for receiving the supply voltage from the voltage source, wherein the control unit is adapted to generate at least one control signal (18, 20) for setting the voltage amplification factor and the signal amplification factor in dependence on the supply voltage; wherein the voltage amplification factor is inversely proportional to the signal amplification factor; and wherein the control unit is adapted to reduce the voltage amplification factor so far that the operation voltage provided by the operation voltage amplifier lies within the allowable operation voltage range when the supply voltage exceeds a maximum allowable operation voltage of the ratiometric sensor.