Step-change sensor for pumped and unpumped operation

The invention provides a step-change sensor for pumped and unpumped operation. A sensor device for sensing at least a proportion of at least one gas component of a gas in a measurement gas space, in particular for detecting oxygen in an exhaust gas of a combustion machine, is proposed. The sensor device includes at least one sensor element. The sensor element includes at least one first electrode and at least one first reference electrode and at least one second reference electrode. The second reference electrode is connected to at least one reference gas channel. The first electrode is connected to the first reference electrode and the second reference electrode by at least one respective solid electrolyte. The sensor element has at least one diffusion element between the first reference electrode and the reference gas channel.