Stmicroelectronics S.r.l.

Sgs-thomson Microelectronics S.r.l.

Sgs Microelettronica Spa

Sgs-thomson Microelectronics S.p.a.

St-ericsson Sa

Salvatore Rosario Musumeci

Raffaele Zambrano

Maria Francesca Seminara

Patrizia Milazzo

Salvatore Raciti

Giuseppe Ferla

Giuseppe Platania

Gianluca Ragonesi

Sergio Palara

Franco Bertotti

Cesare Ronsisvalle

Luciano Gandolfi

Roberto Pellicano

Rosario Pagano

Marianna Sanza

Angelo Raciti

Gaetano Belverde

Maurizio Melito

A LED driver chip includes driver circuits, each being coupled to a different pin and including a fault-detection circuit. Each fault-detection circuit includes a force circuit forcing current to a force node, and a sense circuit including a current sensor coupled to the force node, and a comparator comparing a voltage at the force node to a reference voltage to generate a comparison output. Control circuitry, in a pin-to-pin short detection mode, activates the force circuit of a first of the driver circuits and activates thep sense circuit of a second of the driver circuits, in a pin-to-ground short detection mode, activates the force and the sense circuit of the same driver circuits. The comparison output of the comparator of the activated sense circuit, if is higher or if lower of the reference voltage, indicates if short between pin or to ground, respectively, is present.

LED array driver with channel to channel and channel to ground external PIN short detection

An embodiment LED driver system comprises a power transistor configured to be selectively activated for generating a driving current for an array of LEDs, the power transistor having a first conduction terminal coupled to the array of LEDs and a second conduction terminal coupled to a reference resistor; an operational amplifier having a non-inverting input for receiving a reference voltage, an inverting input coupled to the second conduction terminal of the power transistor, and an output terminal coupled to a first conduction terminal of a transmission gate having a second conduction terminal coupled to a control terminal of the power transistor and a control terminal for receiving an enable signal; and a slew rate control unit configured to control the slew rate of the driving current.

LED array driver system

A LED driver chip includes driver circuits, each being coupled to a different pin and including a fault-detection circuit. Each fault-detection circuit includes a force circuit forcing current to a force node, and a sense circuit including a current sensor coupled to the force node, and a comparator comparing a voltage at the force node to a reference voltage to generate a comparison output. Control circuitry, in a pin-to-pin short detection mode, activates the force circuit of a first of the driver circuits and activates the sense circuit of a second of the driver circuits, in a pin-to-ground short detection mode, activates the force and the sense circuit of the same driver circuits. The comparison output of the comparator of the activated sense circuit, if is higher or if lower of the reference voltage, indicates if short between pin or to ground, respectively, is present.

LED array driver with channel to channel and channel to ground external pin short detection

A multiphase buck converter () is disclosed, comprising: &#x2014;a first buck converter branch (SD, L) comprising a first core section (COR), a first power section (PWR) having a first output node (LX), a first coil () having a first end connected to the first output node (LX), the first power section (PWR) being adapted to be controlled by the first core section (COR) for providing to the coil (L) a coil current (I), the first core section (COR) and the first power section (PWR) being integrated in a chip (IC); &#x2014;a second buck converter branch (SD, L) comprising a second core section (COR), a second power section (PWR) having a second output node (LX), a second coil (L) having a first end connected to the second output node (LX), the second power section (PWR) being adapted to be controlled by the second core section (COR) for providing to the second coil (L) a second coil current (I), the second core section (COR) and the second power section (PWR) being integrated in said chip (IC); &#x2014;a feedback loop adapted to balance said coil currents (I,I). The feedback loop comprises a control block (C_B) that, in order to balance said coil currents, is adapted to compare a first average voltage at the first output node (LX) with a second average voltage at the second output node (LX) and control the first (SD, L) and second branch (SD, L) in order to make said first and second average voltages equal to each other. The control block (C_B) is integrated in said chip (IC) and has a first input directly connected to said first output node (LX) and a second input directly connected to said second output node (LX). The control block (C_B) is adapted to directly obtain said first and second average voltages from the instantaneous voltages of the first (LX) and second (LX) output nodes.

Multiphase buck converter and multiphase buck conversion method

An electronic power supply circuit for a load composed of at least two independent circuit branches connected in parallel to each other, where a first branch requires a different power supply voltage from the power supply voltage of a second branch. The circuit includes a step-up converter, a timer circuit connected to the step-up converter so that the converter generates, alternately, at least a first output voltage able to power the first circuit branch and a second output voltage able to power a second circuit branch, a regulation circuit able to regulate the overvoltages at the ends of an output capacitor of the converter during commutations between the different output voltages; and a commutation circuit able to activate the step-up converter, according to the timer signals coming from the timer circuit, when the output voltage at the ends of the output capacitor has reached the level needed to power the activated branch and regulate the current flowing thereto.

Electronic power supply circuit

A device includes at least two circuit branches, each of said at least two circuit branches comprising at least one LED diode. The device comprises a supply circuit that provides an electric supply of said at least two circuit branches and includes a variable resistance. The device comprises a controller coupled to said at least two circuit branches and suitable for varying said resistance in reply to a variation of the current that flows in one of said at least two circuit branches to vary the electric supply of said at least two circuit branches.

Supply device of circuit branches with LED diodes

A circuit apparatus with LED diodes includes a plurality of circuit branches in which each circuit branch comprises at least one LED diode. The apparatus comprises a device for the supply of said plurality of circuit branches and each circuit branch is connected singularly to the supply device. The supply device comprises a controller suitable for commanding the supply of each circuit branch of the plurality of circuit branches independently from the other circuit branches of the plurality.

Circuit apparatus with LED diodes

A protection circuit for a control terminal of a power device of the type comprising at least one resistive element connected between at least one output terminal of a driver and the control terminal of the power device includes at least one turning-off transistor having its conduction terminals connected to the control terminal of the power device and to at least one output terminal of the driver, respectively. A control terminal is coupled to the control terminal of the power device through a second resistive element.

Protection circuit for faulted power devices

The device uses the horizontal insulating region and the buried layer as the power transistor base and emitter respectively. An epitaxial growth is interposed between the two diffusions needed to form the aforesaid regions and those needed to create the base and the emitter of the transistor of the integrated control circuit.

Manufacturing process for a monolithic semiconductor device comprising at least one transistor of an integrated control circuit and one power transistor integrated on the same chip

The problems normally linked to the creation of a power stage using BJT transistors are overcome realizing the power stage with BMFET transistors.

Method of manufacturing a semiconductor device comprising a control

Semiconductor device comprising a control circuit and a power stage with

The thin buffer layer, very often present in HIMOS devices, is achieved by ion implantation or predeposition of the dopant followed by subsequent diffusion.

Method for manufacturing a conductivity modulation MOS semiconductor

The integrated structure is formed of various circuital components accomplished by diffusion of dopants in a semiconductor substrate. Each component is located inside a respective insulation recess electrically floating in relation to the substrate and the other components.

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Catania, Italy

Salvatore Rosario Musumeci