Multiple controllers connected in parallel to control external circuits such as dc-dc converters so that the external circuits supply power equally to a load such as a microprocessor. All of the controllers are connected and each controller includes an oscillator and a pulse width modulation circuit to synchronize the frequency of all of the oscillators such that the duty cycle of all the oscillators are equal. Each controller includes an over-current protection circuit and an over-voltage protection circuit which will cause the controller with a fault to discontinue supplying power to the load. Each controller further includes a circuit to adjust the duty cycle of the non-faulty controllers when a controller with a fault is caused to discontinue supplying power to the load.

Synchronous current sharing pulse width modulator

Various embodiments are described herein relating to a radar system and associated methods for detecting targets in the presence of certain types of clutter. The radar system generally comprises hardware operatively configured to obtain first and second sets of radar return signals concurrently, first circuitry operatively configured to detect targets in the first and second sets of radar return signals, and second circuitry operatively configured to identify detected targets due to clutter.

Dual beam radar system

A pulse width modulated power supply controller is disclosed which is capable of generating synchronization pulses in such a manner that multiple ones of such power supply controllers in a system are synchronized to the controller having the highest oscillation frequency, without requiring one of the controllers to be implemented as a master and the others implemented as slaves. The power supply controller includes two comparators which are coupled to receive the external capacitor voltage. A first comparator enables a fast charging circuit, such as a current source, for increasing the rate at which the capacitor is charged responsive to the capacitor voltage reaching a first threshold; a single-ended or differential synchronization pulse is also generated, and communicated to the first comparators of other power supply controllers in a multiple controller system. The second comparator, which includes hysteresis in its characteristic, turns off the fast charging circuit at the upper threshold and initiates the discharge of the capacitor. Control of the output and masking of the comparators of the controllers is also based on the operation of the first and second comparators.

A synchronizable power supply controller and a system incorporating the same

Methods and apparatus are disclosed for achieving load balance between parallel inverters in an AC power supply. Load balancing reduces undesirable cross conduction current between the parallel inverters. Load balancing and the resulting reduction in cross conduction current are achieved without the need for common control circuitry between the parallel inverters. Thus, the single-fault protection offered by redundant parallel inverters is not compromised by the disclosed load balancing techniques.

Methods and apparatus for load sharing between parallel inverters in an AC power supply

A circuit having a load connected to ground, a measuring resistor connected in series with the load; a current source feeding current into the load and the resistor, a different amplifier having one output connected to one end of the resistor and having its output connected to a summing point which is an input from the current source, a reference voltage source having one end connected to the summing point, is improved by an impedance converter having its input circuit connected to another end of the resistor and its output connected to another input for the differential amplifier, the latter output being further connected to an opposite end of the reference voltage source thus serving as floating ground for the reference source and the differential amplifier.

Load independent current feeding circuit

Apparatus for synchronizing the oscillators of several clocked direct voltage converters where each direct voltage converter has a control circuit with the oscillator as an integrated component and each control circuit has a connection for a capacitor and a connection for a resistor for defining the oscillator frequency. Commercial elements TDA 4714 and TDA 4716 are preferred as the control circuit. The synchronization is attained by adjusting the frequency of the oscillator of a first direct voltage converter to be higher than the frequency of the oscillators of the remaining direct voltage converters. A pulse sequence with an impulse frequency proportional to the oscillator frequency of the first direct voltage converter is transmitted by the first direct voltage converter to all of the other converters through an element that provides isolation between the different potentials. The pulses of the pulse sequence adjust a predetermined charging state for the capacitors of the other direct voltage converters. The adjustment is repeated at the frequency of the oscillator of the first direct voltage converter.

Synchronizer for commonly clocked converters

Consumers (loads) are often connected to a current supply apparatus via relatively long connecting leads. The lead resistances of the connecting leads and the contact resistances of output sockets, output plugs or the like cause a voltage drop which is proportional to the load current likewise flowing through them. Because of this, the voltage directly across the consumer is smaller than the output voltage of the current supply apparatus and changes continuously with the fluctuations of the load current. By means of the current supply apparatus proposed, the voltage fluctuations on the consumer caused by the lead resistances are intended to be compensated in the simplest possible way. For this purpose, the output voltage is increased in proportion to the load current.

Current supply apparatus

not available for EP0213655Abstract of corresponding document: US4694388Apparatus for synchronizing the oscillators of several clocked direct voltage converters where each direct voltage converter has a control circuit with the oscillator as an integrated component and each control circuit has a connection for a capacitor and a connection for a resistor for defining the oscillator frequency. Commercial elements TDA 4714 and TDA 4716 are preferred as the control circuit. The synchronization is attained by adjusting the frequency of the oscillator of a first direct voltage converter to be higher than the frequency of the oscillators of the remaining direct voltage converters. A pulse sequence with an impulse frequency proportional to the oscillator frequency of the first direct voltage converter is transmitted by the first direct voltage converter to all of the other converters through an element that provides isolation between the different potentials. The pulses of the pulse sequence adjust a predetermined charging state for the capacitors of the other direct voltage converters. The adjustment is repeated at the frequency of the oscillator of the first direct voltage converter.

Arrangement for the synchronization of the oscillators of a multiple switching dc-dc converter

A circuit arrangement which comprises at least one stage which is to be fed by a source voltage from a common voltage source, at least one of these stages comprising a control signal generating circuit which can apply a control signal, to be derived from the source voltage, to a control signal output bus conductor which is common to all stages. A control signal input bus conductor can be connected to the control signal output bus conductor via a central bridge when the source voltage has a value within a first value range and which can be isolated from the control signal output bus conductor by the central bridge when the source voltage has a value within a second value range. Each stage includes a respective control circuit which can be connected to the control signal input bus conductor in order to receive the control signal and which can adjust the stage to a source voltage from the associated value range by application or interruption of the control signal. Thus, the circuit arrangement simply adapts the stages fed by the voltage source to the particular source voltage.

Loesel Walter

Papers

Synchronizer for commonly clocked converters

Current supply apparatus

Arrangement for the synchronization of the oscillators of a multiple switching dc-dc converter

Plural stage circuit with automatic adaptation to first and second voltage ranges of a common voltage source