| 摘要 |
<p>A temperature controlling or detecting device has a circuit which comprises a temperature-sensitive element (1) whose electrical resistance changes with temperature. Changes in the resistance of the said element (1) are detected by an arrangement including a Wheatstone bridge and an operational amplifier (15). The amplifier (15) produces an output signal at a predetermined temperature or at the upper and lower limits of a predetermined temperature range in response to changes in resistance of element (1). At least a sufficient part of the circuit is encapsulated in a resin to prevent ready adjustment of the said predetermined temperature or temperature range.</p> |
