Temperature control device and oscillator

A temperature control device for controlling a temperature of a heated body heated by a heater to a target temperature, the temperature control device comprising:

• a temperature detector that detects a temperature corresponding to the heated body;
• a difference operation unit that operates a digital value corresponding to a difference value between a detected temperature value detected by the temperature detector, and the target temperature;
• a controller that calculates a manipulated variable using the digital value operated by the difference operation unit as an input value and outputs the manipulated variable as the digital value;
• a saturation processing circuit unit that being connected to a rear stage of the controller and including a digital circuit to limit an output value of the controller to a pre-set upper limit value;
• a rewritable storage unit that stores the upper limit value, and the upper limit value being read from a storage area of the rewritable storage unit and being input into the saturation processing circuit unit;
• and
• a conversion unit that converts the output value of the saturation processing circuit unit into an analog signal to output the converted value as a control command value to the heater.