A radiation sensor (10) comprises one or more radiation sensing elements (1) providing an electric signal in dependence of incident radiation, a housing (4, 5) confining the sensing element and permitting incidence of radiation from outside onto the sensing element, plural terminals (7) for supplying electrical power to the sensor and at least for outputting a sensor output signal, and circuitry (2) receiving the electric signal of the sensing element and providing the output signal in accordance with the electric signal of the sensing element. The circuitry comprises a switching signal circuitry for generating an on/off output signal for a switchable component external to the sensor and/or a digital output signal circuitry for providing a multiple bit serial output signal, and the sensor has one output terminal (7a) for outputting the on/off output signal or the multiple bit serial output signal.