Stmicroelectronics (alps) Sas

Stmicroelectronics (grenoble 2) Sas

Stmicroelectronics International N.v.

Optis Circuit Technology, LLC

Telefonaktiebolaget Lm Ericsson (publ)

St-ericsson Sa

Vratislav Michal

Denis Cottin

Michel Ayraud

Nicolas Moeneclaey

Patrik Arno

Jean-Luc Patry

Nicolas Marty

Regis Rousset

The present disclosure is directed to a light-signal communication receiver device including a photo-receiving diode configured to generate a current signal on a first node from a received light signal, a preamplifier configured to convert the current signal on the first node into a voltage signal on a second node, and a differential amplifier including a first input connected to the first node and a second input connected to a third node coupled to the second node via an adjustment circuit. The adjustment circuit is configured to offset the level of the voltage signal of the second node, on the third node, in a controlled manner by a control signal.

Receiver device, reception system, process and light-signal communication method

A circuit can be used for reading out a light sensor. The circuit includes an operational amplifier. A first capacitor has a first electrode coupled to an inverting input of the operational amplifier and a second electrode coupled to a non-inverting output of the operational amplifier. A compensation circuit is coupled between the operational amplifier and the first capacitor. A preset circuit has an input coupled to a first voltage node and an output coupled to the first capacitor. The first voltage node configured to carry a first voltage equal to a preset voltage multiplied by a coefficient.

Ambient light sensor

A band-gap circuit for generating a bandgap reference signal includes a first bipolar transistor and a second bipolar transistor of a same type among PNP and NPN types. The first and second bipolar transistors are configured to generate a current varying proportionally with the temperature. A capacitor is connected between a base and an emitter of one or both of the first and second bipolar transistors.

Bandgap circuit

In an embodiment, a circuit includes a first branch coupled between a first node and a second node, the first branch including a first ceramic capacitor, the first ceramic capacitor including terminals configured to receive a first voltage applied therebetween. The circuit further includes a second branch coupled between the first node and a third node, the second branch including a second ceramic capacitor that is substantially identical to the first ceramic capacitor, the second ceramic capacitor including terminals configured to receive a second voltage applied therebetween. The circuit further includes a control circuit configured to modify the second voltage until a first current passing through the second node is substantially equal to a second current passing through the third node.

Floating voltage measuring circuit and method

In an embodiment a power converter includes a first capacitor and a second capacitor coupled in series with the first capacitor, wherein the converter is configured to charge, during a first phase, the first and second capacitors by a supply voltage so that a voltage across terminals of each of the first and second capacitors is substantially equal to half the supply voltage and discharge, during a second phase, the second capacitor to a third capacitor.

Flying capacitor topology for DC or AC output from a DC source

A circuit includes an amplifier having a first power terminal configured to be coupled to a supply voltage and a second power terminal configured to be coupled to a reference potential. The circuit further includes a first impedance element coupled between a first input terminal of the amplifier and a first output terminal of the amplifier. The circuit additionally includes a second impedance element coupled between the first input terminal and the reference potential. The amplifier is configured to output a first voltage at a second output terminal of the amplifier in response to the supply voltage being greater than an output voltage at the first output terminal of the amplifier. The amplifier is further configured to output a second voltage at the second output terminal of the amplifier in response to the supply voltage being less than the output voltage at the first output terminal of the amplifier.

Voltage detector circuit

An embodiment circuit includes a first voltage divider coupled between a first voltage level and a ground potential. The circuit further includes an error amplifier having a first input terminal coupled to a node between a first resistive element and a second resistive element of the first voltage divider. The circuit further includes a second voltage divider coupled between a second voltage level and a reference voltage, wherein a second input terminal of the error amplifier is coupled to a node between a third resistive element and a fourth resistive element of the second voltage divider, and wherein an output voltage of the error amplifier is configured to control a potential difference between the first voltage level and the second voltage level.

Differential sensing circuit of a floating voltage source

A method and apparatus for detecting a critical duty cycle that maximizes an output power of a boost converter is provided. In the method and apparatus, the boost converter may be operated at or below the critical duty cycle. In the method and apparatus, a first voltage that is a function of an output voltage of a boost converter and voltage drops across a first set of parasitic resistances of the boost converter is detected. A second voltage that is a function voltage drops across a second set of parasitic resistances of the boost converter is also detected. The voltages are compared to determine the critical duty cycle and the boost converter is operated in accordance with a duty cycle that does not exceed the critical duty cycle.

Boost converter maximal output power detector allowing optimal dynamic duty-cycle limitation

A circuit including: a plurality of first switches connected in parallel between a first terminal and a second terminal; and a control circuit capable of implementing the following steps at each period of a clock signal: comparing the voltage between the first and second terminals with a reference voltage; if the voltage between the first and second terminals is greater than the reference voltage, turning on one of the first switches without modifying the state of the other switches; and if the voltage between the first and second terminals is smaller than the reference voltage, turning off one of the first switches without modifying the state of the other switches.

Circuit to implement a diode function

A switched-mode power supply device includes a power switch configured to transfer power from a supply line to a load in switched-mode; a first oscillator configured to operate at a frequency proportional to a voltage of the supply line; a second oscillator configured to operate at a frequency proportional to a voltage of the load; and a regulator configured to operate the power switch according to a duty cycle based on a ratio between the first and second oscillator frequencies.

Single-shot duty cycle generator for a switched-mode power supply

A method for calibrating a resistance value comprises the steps of measuring a value of a reference capacitor, and adjusting a variable resistor based on the measured value of the reference capacitor. The method may more specifically comprise the steps of directing a constant current through the reference capacitor during a reference time interval; after the reference time interval, directing the constant current through the variable resistor; and varying the variable resistor value progressively by varying a control signal until a voltage of the variable resistor reaches a voltage of the reference capacitor.

Resistor calibration using a MOS capacitor

A system for measuring an output current of a DC-to-DC converter with a transistor power stage includes a voltage measuring circuit and an impedance. The voltage measuring circuit, which is connected to the output of the power stage of the DC-to-DC converter, measures an average voltage drop on impedances of the transistors of the power stage. The impedance, which is connected to an output of the voltage measuring circuit, reproduces the impedances of the transistors of the power stage and is traversed by a scaled version of the current output of the voltage measuring circuit.

Absolute value current-sensing circuit for step-down DC-to-DC converters with integrated power stage

A peak efficiency detection system may include a switched power supply (SPS) module providing an output supply signal. The SPS module may have an internal node, and a plurality of SPS circuits configured to generate the output supply signal on the internal node. A dead type module may generate control signals. A central node external to the SPS module may deliver the output supply signal to a load module. A power stage size control module may generate control signals for controlling the SPS module. A peak-efficiency detection (PED) module may receive the output supply signal from the central node, the control signals from the SPS module, and the control signals from the power stage size control module. The PED module may generate a signal representative of an efficiency of the SPS module.

Switched mode power supply peak-efficiency detection

A charge-pump device receives two complementary driving signals and a DC signal that are applied to a charge-pump stage containing a full-wave rectifier bridge configured to deliver a DC output signal. The bridge includes active switches controllable by control signals present at two control nodes. The charge-pump device further receives complementary auxiliary signals that are respectively synchronous with the complementary driving signals but have faster edges. Two resistive capacitive filters filter the complementary auxiliary signals to generate control signals at the two control nodes for controlling actuation of the active switches in the bridge.

Growing community of inventors

Grenoble, France

Vratislav Michal