Abstract: An energy saving DC-DC converter circuit is disclosed having two energy efficient means which operate in tandem, an energy conserving means (30, 8, 1) and a voltage doubling means (26). These energy efficient means are applied in combination with elements commonly found in DC-DC converter circuits, namely an AC voltage generator (2), a transformer (3) for stepping up the generated AC voltage, and means (31) for storing the converted DC voltage. The energy conserving means is connected to the DC voltage storage means (31). It comprises a resettable inhibit circuit (1) which cuts off the provision of DC voltage for conversion for a predetermined interval when the output of the converter exceeds a predetermined level. The voltage doubling means is reponsive to outputs of the inhibit circuit (1) of the energy conserving means and the AC voltage generator (2). It provides a phase inverted waveform of the generated AC voltage on one of two leads to the AC voltage step-up transformer (3).

Abstract: A circuit arrangement to provide a fixed voltage source in series with an arbitrarily chosen impedance of any magnitude and phase shift having very low power dissipation and capable of being fabricated on silicon integrated chips is disclosed. The circuit arrangement includes a sensing resistor to sense the output current of a power converter which is amplified and fed back with an appropriate phase shift to control the output voltage of the converter. An independent control signal may be combined with the fed back voltage to change the chosen impedance to another type of impedance.

Abstract: A switching voltage regulator (86) is controlled to produce a low output voltage when the power is first turned on and subsequently to produce a high output voltage after a predetermined length of time has elapsed, thereby eliminating overloads due to initial surge currents.

Abstract: The ferromagnetic core of a transformer in a switching regulator power supply is configured to improve the efficiency of the supply. Since the switching times and their resultant losses occupy a greater percentage of the energy-storage energy-transfer cycle as the operating frequency increases, efficiency is increased by narrowing the operating frequency range. There is provided a transformer core which allows the inductances in the transformer windings to vary during each energy-storage and energy-transfer half cycle. The initial inductance can be chosen such that a predetermined time interval is added to each half cycle regardless of output load to thereby decrease the operating frequency range.

Abstract: The input dc voltage is used to operate an astable multivibrator, the output of which is supplied to an emitter-follower that is coupled to an amplifier through a current-limiting resistor, so that a transistor across the input of the amplifier can controllably reduce the amplification of the amplifier. The amplifier output is supplied to the primary winding of a transformer which has a secondary winding that feeds a rectifier to supply the output dc voltage. The output dc voltage is coupled back to the control transistor through a Zener diode and a resistor in series, so that when the output voltage exceeds the Zener diode voltage, the control transistor will reduce the amplification of the amplifier, reducing the amplitude of the rectified ac voltage and hence regulating the output voltage.

Abstract: Apparatus for control of direct current by means of systematic switching and progressive variation of magnetic flux in associated magnetic paths. Subdivision of the input DC power between two transformer devices permits transformation by controlled electromagnetic induction into stabilized outputs which may be recombined into continuous DC power at controlled voltage or current levels.

Abstract: A self-powered fiber optic interconnect system in which electrical output from data transmitting equipment is converted in a transmitter unit to optical signals in a fiber optic cable for transmission to a receiver unit for reconversion to electrical signals for data receiving equipment and a power source separate from the transmitting and receiving equipment so that the interconnect system can be completely interchangeable with an electrical copper wire interconnect system. When the data transmitting equipment is a computer with parallel data output, the transmitter unit converts the parallel output to serial data output for transmission to the receiver unit over a single fiber optic cable and the receiver unit reconverts the output to parallel data for the data receiving equipment.

Abstract: Power supply having means for developing a voltage overload signal representing a current overload condition in the power supply and then reducing the output current from the power supply as a result of the voltage overload signal. The voltage overload signal is applied to a servo or error amplifier to cause the error signal therefrom to change in a manner to reduce the power supply output voltage which in turn is fedback to the said amplifier to cause output current foldback.

Abstract: A surge current protection circuit includes an input terminal supplied with a rectified alternating voltage, an output terminal to be connected to a load, and a semiconductor controlled rectifier having its anode and cathode electrodes connected in series between the input and output terminals. The collector and emitter electrodes of a control transistor are connected between the gate and cathode electrodes of the rectifier. The base-emitter voltage is supplied with any sharp transients, and the transistor becomes conductive before the rectifier if the transients are sharp enough and of high enough amplitude. Conduction of the transistor prevents the semiconductor controlled rectifier from conducting surge currents and protects circuits connected in series with the rectifier.

Abstract: Electromagnetic interference shields are connected to electrical reference points from specially selected null or "center tap" connection points where noise voltages induced in the surface of the electromagnetic shield are substantially balanced out such that injection of such induced interference noise voltages to the connected reference points are substantially reduced. Special selection of isolated reference points for the input and output circuits as well as a special combination of electromagnetic interference shields substantially reduces the electromagnetic interference emanations from an electrical power supply circuit incorporating an inverter and transformer windings therewithin which normally constitute sources of unwanted electromagnetic interference signals unless suppressed.