Abstract:
An A.C./D.C. converter including a filtering capacitor and further including a first branch essentially including a first rectifying circuit and a current limiting circuit; a second branch essentially including a second rectifying circuit, the series voltage drop of which is limited to that of the switches forming it; and a selection circuit for selecting one of the two rectifying circuits.
Abstract:
A high-voltage oscillator including a first normally-on switch in series with a resonant circuit, a second normally-on switch in parallel with the resonant circuit, and a control circuit preventing the simultaneous conduction of the two switches.
Abstract:
A method and a circuit for detecting an overheating of an electronic switch of power supply of a load by an A.C. voltage, in which a voltage representative of the temperature in the vicinity of the switch is compared with a threshold, the result of this comparison being sampled at frequency corresponding to an even multiple of the frequency of the A.C. power supply voltage, to provide a signal indicative of the fact that a temperature threshold has been exceeded.
Abstract:
A method and a circuit for detecting the state of supply of a load by a variable voltage, including measuring the difference between values representative of the variable supply voltage and of a voltage across the load.
Abstract:
A window comparator of an A.C. input voltage, including, between two terminals of application of a voltage representative of the voltage to be measured, two first transistors of a first type, each first transistor being assembled as a current mirror on the second transistor having a first conduction terminal connected to one of the application terminals, the two second transistors having a second common conduction terminal; and two third transistors of a second type assembled as a current mirror between the common conduction terminal of the second transistors and a current source, a D.C. voltage being applied on a first terminal of the current source and an output signal being provided by a second terminal of the current source.
Abstract:
A method and a circuit for detecting an overheating of an electronic switch of power supply of a load by an A.C. voltage, in which a voltage representative of the temperature in the vicinity of the switch is compared with a threshold, the result of this comparison being sampled at frequency corresponding to an even multiple of the frequency of the A.C. power supply voltage, to provide a signal indicative of the fact that a temperature threshold has been exceeded.
Abstract:
A window comparator of an A.C. input voltage, including, between two terminals of application of a voltage representative of the voltage to be measured, two first transistors of a first type, each first transistor being assembled as a current mirror on the second transistor having a first conduction terminal connected to one of the application terminals, the two second transistors having a second common conduction terminal; and two third transistors of a second type assembled as a current mirror between the common conduction terminal of the second transistors and a current source, a D.C. voltage being applied on a first terminal of the current source and an output signal being provided by a second terminal of the current source.
Abstract:
A bidirectional switch, including a first bidirectional switch between two power terminals of the switch, a low-voltage storage element between a first power terminal and a control terminal of the switch, and a control stage adapted to cause, upon each halfwave beginning of an A.C. supply voltage applied between the power terminals and when the switch is on, the charge of the storage element with a biasing depending on the sign of the halfwave.