Battery-powered device for measuring temperatures

A battery-powered device for measuring temperatures is described, having a temperature sensor whose ohmic resistance alters according to the temperature, and which is connected in a branch of a full or half measuring bridge, to which a reference voltage is applied, and whose bridge voltage is amplified by an amplifier whose output signal is a measure of the temperature to be measured. The device according to the invention is characterised by a combination of the following features: a) a first switch (4) applies the reference voltage or the reference potential to the bridge (1), depending on the circuit state; b) an operational amplifier (5) without additional zero or temperature compensation is used as the amplifier; c) a second and a third switch (6, 7) connect the output terminal of the operational amplifier with a memory circuit (8) for the output voltage, or with one input terminal of a subtractor (9) and the memory circuit with the other input terminal of the subtractor, depending on the circuit state; d) a control circuit (11) controls the switches so that in a first operating status, the reference potential is applied to the measuring bridge, and the memory circuit stores the output offset voltage of the operational amplifier, and a second operating status, the reference voltage is applied to the measuring bridge and the subtractor ... Original abstract incomplete.