| 摘要 |
A thermometer is disclosed which utilizes a thermistor as a temperature sensor, controlling the frequency of oscillation of an oscillator circuit. The output pulses from that circuit are frequency-divided during a fixed time interval by a variable frequency divider circuit, with the division ratio being successively varied during that interval in accordance with the cumulative number of pulses output from the variable frequency divider circuit, counted by a counter circuit, with the variations of the frequency division ratio being such as to accurately compensate for the non-linear temperature/resistance characteristic of the thermistor. The cumulative count of pulses output from the variable frequency divider circuit at the end of the fixed time interval is proportional to temperature, and is displayed as temperature by a digital display. The thermometer is suited to mass-production low-cost manufacture, yet can be miniaturized, lightweight and accurate.
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