Abstract: A spacecraft (10) includes N paralleled power converters (24a, 24b . . . ) for producing current pulses in response to converter synchronizing pulses. The current pulses are integrated (28) to produce an operating direct voltage. The synchronizing pulses are produced in a recurrent cycle by a synchronizer (30). The synchronizer includes a voltage divider (320) with equal series-connected elements (324a, 324b . . . ), each of which is paralleled by a shorting switch (330a, 330b . . . ). A sawtooth signal generator (310) produces a sawtooth signal (312), which is applied in common to each of a plurality of comparators (332a, 332b . . . ). The voltage divider (320) is connected across a reference voltage (318), to produce a plurality of reference voltages at the taps (328a, 328b). Each comparator (332) compares the sawtooth ramp (314) with one of the reference voltages, so that the comparators trigger in sequence as the ramp rises. The comparators trigger at times corresponding to equal phase increments of 360.

Abstract: Dead time circuitry for ensuring that no two switching devices in a half-bridge, or in the same leg of a full-bridge, are conductive simultaneously employs a symmetrical delay circuit which independently delays the rising and falling edges of each signal pulse.

Abstract: A phase shift generator receives two input pulse signals and generates two output pulse train signals, each having a 50% duty cycle, which are phase-shifted in a range from 0.degree. to 180.degree. by an amount proportional to the duty cycle of the input pulse train signals and also proportional to the power supply load requirement.

Abstract: A primary side power supply controller includes a full-bridge/half-bridge driver and is capable of being implemented on a single HVIC chip. Control circuitry enables operation in PWM, resonant, and phase-shift control modes. In the phase-shift control mode, a phase shift generator receives two input pulse train signals and generates two output pulse train signals, each having a 50% duty cycle, which are phase-shifted in a range from 0 to 180.degree. by an amount proportional to the duty cycle of the input pulse train signals and also proportional to the power supply load requirement. Dead time circuitry for ensuring that no two switching devices in a half-bridge, or in the same leg of a full-bridge, are conductive simultaneously employs a symmetrical delay circuit which independently delays the rising and falling edges of each signal pulse.

Abstract: An on-chip DC power supply uses at least one series pass element which conducts responsive to a gating signal obtained by clamping an input potential to a preselected polarity and amplitude. A charge storage element serves to maintain an output voltage which is clamped to a predetermined maximum value. An output regulator provides a substantially constant second output voltage at a magnitude less than the output voltage set by the output clamping means.

Abstract: An integratable circuit for controlling the turn-off time-rate-of-voltage-change of a non-regenerative power switching device (such as a field-effect transistor, an insulated gate transistor and the like) uses a single capacitive element, in conjunction with a first current source, to provide a ramp voltage generator which is operative only if a ramp generator terminal is disconnected from a circuit common potential. The circuit uses a second current source and a controlled-conduction device to provide a control electrode drive signal to the at least one power switching device, controlling the flow of current through a load from a unipolarity or bipolarity source. The voltage across the controlled-conduction circuit of the power switching device then active is applied in attenuated form to another input of the ramp voltage generator to control the load voltage time-rate-of-change during load current turn-off.

Abstract: An integratable load voltage sampling circuit utilizes a plurality of current-mirrors. One of the current mirrors is switched into conduction during a load-current conduction time interval, while another current mirror operates during the entire source half-cycle during which the first current mirror is pulsed to conduct. The total current from the plurality of current mirrors is summed and compared to a reference level; the difference in magnitude between the sampled and reference values is integrated, with respect to time, to provide a load conduction-angle adjustment signal having a magnitude varying as the root-mean-square magnitude of the average load voltage.

Abstract: Control apparatus for producing a control signal indicating that a physical variable has reached a userselected level. A transducer generates for the control apparatus electrical pulses having a repetition period which is a function of the physical variable. The control apparatus repeatedly counts clock pulses in response to the transducer pulses to provide a first digital signal representative of the repetition period of the transducer pulses. The apparatus also repeatedly generates a second digital signal corresponding to the user-selected level of the physical variable by adding to a preset binary code a binary amount related to a userselected voltage. The first and second digital signals are compared to produce the control signal for a switching circuit which responds thereto. The comparison is overriden if an analysis of most significant bits of the first digital signal shows that the physical variable varies beyond a predetermined level.