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RC电路充电的指数电压/时间关系可用于线性化热敏电阻近似成指数的电阻/温度特性。经变换后的输出信号为线性、直接正比于绝对温度的频率。使用标准的、廉价的热敏电阻,在75K的温度范围内,温度误差可小于0.5K。误差的存在主要是由于热敏电阻R(T)特性不完全服从指数关系。这种电路可用于线性化任何输入/输出信号为指数关系的传感器。也可以得到正比于输入电压对数值的输出(即正比于以dB表示的输入信号)。
The exponential voltage / time relationship for RC circuit charging can be used to approximate the linearized thermistor to an exponential resistance / temperature characteristic. The transformed output signal is linear and directly proportional to the frequency of absolute temperature. Using standard, inexpensive thermistors, the temperature error can be less than 0.5K over the 75K temperature range. The error is mainly due to the thermistor R (T) characteristics do not completely follow the exponential relationship. This circuit can be used to linearize any sensor whose input / output signal is exponential. You can also get an output proportional to the log of the input voltage (that is, proportional to the input signal in dB).