Energy conserving apparatus for regulating temperature of monitored device

Abstract

Abstract An apparatus for controlling the temperature of a device whose temperature is to be stabilized within a preset range is disclosed. The apparatus is particularly applicable to stabilizing the temperature, and thus frequency of operation of, a crystal controlled oscillator, without expending additional energy in specialized crystal heating apparatus. The apparatus preferably includes first and second power supply regulators coupled to a source of unregulated voltage. The second power supply regulator preferably has a higher output voltage than the first power supply regulator and the outputs of the two regulators are coupled together. The cyrstal is attached to the second regulator so that heat generated by the second regulator is dissipated in the crystal. A temperature sensing device is coupled to the crystal and generates a signal proportional to the temperature of the crystal. The signal from the temperature sensing device is fed to a comparator which compares the signal from the temperature sensing device with a reference voltage. The output of the comparator is then coupled back to a control input of the second regulator so as to turn the second regulator off and first regulator on when the temperature of the crystal exceeds a preset value. When the crystal temperature decreases, the second regulator is turned on, and the first regulator off. Accordingly, heat from a power supply regulator, which would otherwise be dissipated in a heat sink, is used to maintain the temperature of the crystal within a preset range.

Inventors

• 👤 Gerald Block

Bibliographic Details