Abstract: An improved electronic oscillator circuit suitable for use in an isolating DC-to-DC converter circuit, and an improved isolating DC-to-DC converter circuit. In one embodiment, an integrated circuit coupled to a transformer includes an oscillator and an output driver. The integrated circuit is preferably fabricated using a silicon-on-insulator technology. The oscillator outputs an alternating pulse signal defined by electrical characteristics of components other than the transformer. The alternating pulse signal is coupled to the output driver, the alternating output of which is coupled to corresponding legs of the primary winding of the transformer. The secondary winding of the transformer provides an electromagnetically coupled isolated output which may be rectified and filtered to produce a DC output voltage. Additional functionality, such as current protection circuitry for the improved circuits, may be readily added to the integrated circuit at little or no increase in cost.

Abstract: An improved electronic oscillator circuit suitable for use in an isolating DC-to-DC converter circuit, and an improved isolating DC-to-DC converter circuit. In one embodiment, an integrated circuit coupled to a transformer includes an oscillator and an output driver. The integrated circuit is preferably fabricated using a silicon-on-insulator technology. The oscillator outputs an alternating pulse signal defined by electrical characteristics of components other than the transformer. The alternating pulse signal is coupled to the output driver, the alternating output of which is coupled to corresponding legs of the primary winding of the transformer. The secondary winding of the transformer provides an electromagnetically coupled isolated output which may be rectified and filtered to produce a DC output voltage. Additional functionality, such as current protection circuitry for the improved circuits, may be readily added to the integrated circuit at little or no increase in cost.

Abstract: An improved electronic oscillator circuit suitable for use in an isolating DC-to-DC converter circuit, and an improved isolating DC-to-DC converter circuit. In one embodiment, an integrated circuit coupled to a transformer includes an oscillator and an output driver. The integrated circuit is preferably fabricated using a silicon-on-insulator technology. The oscillator outputs an alternating pulse signal defined by electrical characteristics of components other than the transformer. The alternating pulse signal is coupled to the output driver, the alternating output of which is coupled to corresponding legs of the primary winding of the transformer. The secondary winding of the transformer provides an electromagnetically coupled isolated output which may be rectified and filtered to produce a DC output voltage. Additional functionality, such as current protection circuitry for the improved circuits, may be readily added to the integrated circuit at little or no increase in cost.

Abstract: An improved electronic oscillator circuit suitable for use in an isolating DC-to-DC converter circuit, and an improved isolating DC-to-DC converter circuit. In one embodiment, an integrated circuit coupled to a transformer includes an oscillator and an output driver. The integrated circuit is preferably fabricated using a silicon-on-insulator technology. The oscillator outputs an alternating pulse signal defined by electrical characteristics of components other than the transformer. The alternating pulse signal is coupled to the output driver, the alternating output of which is coupled to corresponding legs of the primary winding of the transformer. The secondary winding of the transformer provides an electromagnetically coupled isolated output which may be rectified and filtered to produce a DC output voltage. Additional functionality, such as current protection circuitry for the improved circuits, may be readily added to the integrated circuit at little or no increase in cost.

Abstract: To effect power control of a power amplifier 2 having three amplifier stages 3, 4 and 5 used to amplify input signals modulated in accordance with a variable envelope modulation scheme, there is used a power amplifier 2 having a gain which reduces as the supply voltage to the power amplifier 2 reduces, and the output power POUT of the power amplifier 2 is controlled by regulation of the supply voltage VS. Taking advantage of the reduction in gain of the power amplifier 2, it is ensured that, in respect of each respective amplifier stage 3, 4 and 5 and at each respective value of the supply voltage in the voltage control range, the output power POUT of the respective amplifier stage 3, 4 and 5 is less than the saturation output power PSAT of the respective amplifier stage 3, 4 and 5. As a result, distortion of the signal is reduced. The power control technique improves efficiency over known techniques of backing off the output power and using a variable gain amplifier stage to control the output power.

Abstract: To effect power control of a power amplifier 2 having three amplifier stages 3, 4 and 5 used to amplify input signals modulated in accordance with a variable envelope modulation scheme, there is used a power amplifier 2 having a gain which reduces as the supply voltage to the power amplifier 2 reduces, and the output power POUT of the power amplifier 2 is controlled by regulation of the supply voltage VS. Taking advantage of the reduction in gain of the power amplifier 2, it is ensured that, in respect of each respective amplifier stage 3, 4 and 5 and at each respective value of the supply voltage in the voltage control range, the output power POUT of the respective amplifier stage 3, 4 and 5 is less than the saturation output power PSAT of the respective amplifier stage 3, 4 and 5. As a result, distortion of the signal is reduced. The power control technique improves efficiency over known techniques of backing off the output power and using a variable gain amplifier stage to control the output power.