Stmicroelectronics(tours) Sas

Stmicroelectronics International N.v.

Romain Launois

Yannick Hague

Benoit Renard

Guillaume Thiennot

Disclosed herein is a voltage converter including input nodes configured to receive an input voltage, output nodes configured to deliver an output voltage, a rectifying bridge coupled between the input nodes and the output nodes, a capacitor and a resistor series-coupled between the output nodes, and a thyristor coupled between one terminal of the resistor and a given one of the output nodes, wherein the thyristor is configured to allow flow of a positive current from the resistor to the given one of the output nodes. A control input is configured to receive a control signal, wherein the control signal biases a gate of the thyristor to control the flow of current through the thyristor. transient voltage suppressor circuit is coupled to the gate of the thyristor, configured to activate the thyristor upon exceeding a threshold voltage.

Voltage converter

A bidirectional PFC system includes a high-frequency branch with a first transistor connected between an IO node and a high-frequency tap, and a second transistor connected between the high-frequency tap and a reference node, and a low-frequency branch with a first thyristor connected between the IO node and a low-frequency tap, and a second thyristor connected between the low-frequency tap and the reference node. An inductor is connected between the first node and the high-frequency tap. A first capacitor is connected between the first node and the low-frequency tap. The first node and the low-frequency tap are coupled to input terminals. A control circuit generates first and second gate drive signals for the transistors so as to modify an AC signal at the input terminals such that the AC current falls below a holding current of the second thyristor prior to zero crossing of the AC voltage.

Commutation assistance by controlling the shape of the current wave in a bidirectional totem pole converter

A converter includes first and second transistors coupled between first and second nodes, and first and second thyristors coupled between the first and second nodes. The converter is controlled for operation to: in first periods, turn the first transistor and second thyristor on and turn the second transistor and the first thyristor off, and in second periods, turn the first transistor and the second thyristor off and turn the second transistor and the first thyristor on. Further control of converter operation includes, for a third period following each first period, turning the first and second transistors off, turning the second thyristor off, and injecting a current into the gate of the first thyristor. Additional control of converter operation includes, for a fourth period following each second period, turning the first and second transistors off, turning the first thyristor off, and injecting a current into the gate of the second thyristor.

Voltage converter with thyristor gate controlled to conduct a reverse current

A voltage converter includes a circuit formed by a parallel association, connected between first and second nodes, of a first branch and a second branch. The first branch includes a first controlled rectifying element having a first impedance. The second branch includes a resistor associated in series with a second rectifying element having a second impedance substantially equal to the first impedance. The second rectifying element may, for example, be a triac having its gate coupled to receive a signal from an intermediate node in the series association of the second branch. Alternatively, the second rectifying element may be a thyristor having its gate coupled to receive a signal at the anode of the thyristor.

A voltage converter delivers an output voltage between a first and a second node. The voltage converter includes a capacitor series-coupled with a resistor between the first and second nodes. The resistor is coupled in parallel with a bidirectional switch receiving at its control terminal a positive bias voltage referenced to the second node.

A circuit includes two input nodes and two output nodes. A rectifier bridge is coupled to the input and output nodes. The rectifier bridge includes a first and second thyristors and a third thyristor coupled in series with a resistor in series. The series coupled third thyristor and resistor are coupled in parallel with one of the first and second thyristors. The first and second thyristors are controlled off, with the third thyristor controlled on, during start up with resistor functioning as an in in-rush current limiter circuit. In normal rectifying operation mode, the first and second thyristors are controlled on, with the third thyristor controlled off.

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Tours, France

Romain Launois