A temperature-compensated transistor power converter

Summary form only given, as follows. There are many circuit applications involving the use of transistors where it is necessary, because of the unavoidable presence of vacuum tubes, to have a high dc voltage when only the basic transistor supply voltages are available. This high voltage can be obtained by using a transistor power converter. The power converter is an rf type power supply using a transistor to make the power conversion. Basically it is composed of a transistor oscillator. step-up transformer, dc rectification and filtering. The oscillator operates with a low supply voltage and the frequency may be set high enough so that the transformer and filter components will be small. It is often necessary to operate systems, which may include a power converter, over a wide temperature range. When a constant output voltage from the converter is needed, some form of temperature stabilization must be used to compensate for the change in the transistor parameters. Presented in this paper is a transistor power converter having temperature stabilization to reduce the output voltage variation. The converter uses a P-N-P alloy-junction power transistor to make the power conversion and delivers an output of 0.85 W. The output voltage is 655 V having a variation of ± 15 volts when using a temperature compensating network employing a thermistor. This voltage variation, over the temperature range of -40°C to + 65°C. is small compared to the uncompensated converter that changes from 440-725 V over the same range.