Stmicroelectronics S.r.l.

Infineon Technologies Austria Ag

Infineon Technologies Ag

International Rectifier Corporation

Davide Giacomini

Simone Fabbro

Wolfgang Frank

Tommaso Bacigalupo

Markus Winkler

Enrico Bianconi

Paulus Petrus Bernardus Arts

An apparatus comprises a power source connected to a buffer capacitor. The apparatus comprises a first switch connected between the buffer capacitor and a driven switch. The buffer capacitor is charged by the power source when the first switch is turned off. The apparatus comprises a comparator. The comparator monitors the charging of the buffer capacitor. In response to the buffer capacitor reaching a threshold amount of charge, the comparator turns on the first switch to initiate a charge redistribution of charge from the buffer capacitor to the driven switch.

Charge redistribution for powering a driven switch

An apparatus comprises an energy transfer device configured to supply power from a primary side of an isolation barrier through the isolation barrier to a secondary side of the of the isolation barrier for driving a gate of a switch for controlling output of the switch at the secondary side. The apparatus comprises a monitoring component. The monitoring component is configured to monitor an operating state of the switch. The monitoring component is configured to evaluate the operating state to determine whether a fault has occurred, perform a countermeasure, and/or provide a signal of the fault.

Power transfer, gate drive, and/or protection functions across an isolation barrier

An example controller for a flyback power converter includes a secondary-side circuit comprising a secondary-side controller. The secondary-side controller is configured to sense an electrical characteristic of a secondary-side output of the flyback power converter, select, based on the sensed electrical characteristic, a power mode, and transmit, over a communication channel, a control message specifying the selected power mode. A primary-side circuit of the controller includes a primary-side controller. The primary-side controller is configured to receive, over the communication channel, the control message specifying the selected power mode and control primary-side flyback drive circuitry of the primary-side circuit to drive a primary-side output of the flyback power converter according to the selected power mode so as to control a value of the electrical characteristic of the secondary-side output of the flyback power converter.

Control loop for flyback power converter

A level shifting circuit provides a reference bias voltage to permit signal transfer between two circuits with different common voltage reference levels. The bias voltage is less than a common voltage reference level for either of the two connected circuits. By providing the bias voltage, the range of variation for the common voltage reference levels between the two circuits is increased when the reference voltages float with respect to each other. The level shifting circuits permit signals to be transferred from a low voltage to a high voltage circuit with increased reliability and noise immunity, and vice versa. The level shifting circuit is particularly useful for driving a half bridge switch configuration, and transmitting a floating current sense signal.

High voltage level shifting IC with under-ground voltage swing withstanding capability

A class AB CMOS output stage for an operational amplifier with a rail-to-rail output swing includes a pair of complementary control transistors connected in opposing phase to each other. Connection of the complementary control transistors is made between driving nodes of a pair of complementary output transistors driven by a differential signal. The differential signal is provided by a pair of differential signal input lines connected to an input stage of the operational amplifier. Biasing of the pair of complementary control transistors is by the differential signal.

Class AB CMOS output stage for operational amplifier

A MOS integrated multistage differential single ended amplifier circuit includes an input circuit generating two differential current outputs, and an output circuit. The output circuit includes a current mirror circuit including two current generators and two branches into which are injected two currents each corresponding to a difference between a bias current generated by a respective current generator and a respective differential current output of said input circuit. The output circuit also includes two diode-connected MOS transistors forming respective current mirrors with the two current generators through which the differential output currents are respectively forced, mirroring the differential output currents on the current generators, respectively, and with a certain mirroring ratio. Two voltage reference MOS transistors are also provided having gates connected to injection nodes of the differential output currents on the diode-connected MOS transistors. A load transistor is also provided for the current mirror. A gate of each of the voltage reference MOS transistors may be dimensioned to make a sum of currents flowing therethrough corresponding to a sum of the signal currents in the branches of the current mirror circuit of the output stage divided by twice a mirroring ratio between the load transistor and the diode-connected MOS transistor of said current mirror circuit.

Low offset output stage for precision comparators

A generator circuit for a reference voltage independent of temperature variations uses a Brokaw cell biased by a current generator. The generator circuit includes a start-up circuit for delivering a current to the load of the generator using a transistor from the power-on instant until the switching on of the Brokaw cell and the consequent switching-off of the transistor. The circuit further includes a first field effect transistor having a gate coupled to a bandgap voltage node of the Brokaw cell and operatively connected in series with at least one diode between a biasing current generator of the start-up circuit and ground. The circuit also includes a second bipolar junction transistor having a base coupled to the power supply node of the Brokaw cell and operatively connected to a load resistance that is, in turn, connected to the supply rail and to the output transistor of the Brokaw cell for supplying current to the load during the start-up phase.

Generator circuit for a reference voltage that is independent of

The turn-on delay of a current mode switching converter is reduced by an error summing block including a window comparator to the input of which is fed the output voltage of the converter before being filtered by the low pass filter and to which a low threshold and high threshold reference voltages are applied, both of which are referred to the reference voltage of the converter. The error summing block also includes a differentiating circuit whose input is coupled to the so defined 'under' output of the window comparator and outputting a pulse of a preestablished duration at the incoming of a rising front of the input signal. Two amplifiers of the same gain K, are also provided, and both are enableable for outputting an amplified signal only when enabled. In addition, two summing circuits are also included. One summing circuit adds the reference signal of the converter (Vref), and the other the feedback signal of the output voltage filtered by the low pass filter to the respective signals amplified by the enabling amplifiers when enabled.

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Valdengo, Italy

Davide Giacomini