Stmicroelectronics (Grenoble 2) Sas

St-Ericsson Sa

Stmicroelectronics (Rousset) Sas

Stmicroelectronics S.a.

Stmicroelectronics International N.v.

David Chesneau

Helene Esch

Francois Amiard

Xavier Branca

Christophe Bernard

Vincent Binet

Christophe Premont

Mathilde Sie

Benoît Labbe

Eric Feltrin

An asynchronous finite state machine has states coupled by transitions each implemented by a flip-flop. Each flip-flop supplies a bit of a state of arrival of the corresponding transition, and receives a bit of an initial state of this transition on its data input and a first signal dedicated to the flip-flop on its control input. A circuit supplies, for each transition, a second signal of request for the transition. Another circuit generates based on the second signals, at each request for a transition and in the absence of a pulse of the first signals, a pulse of the first signal dedicated to the flip-flop of this transition, and a pulse of the first signal dedicated to each flip-flop supplying a bit to the flip-flop of the transition.

Asynchronous state machine for a switching converter

An embodiment voltage converter includes a first transistor connected between a first node of the converter and a second node configured to receive a power supply voltage, a second transistor connected between the first node and a third node configured to receive a reference potential, a first circuit configured to control the first and second transistors, and a comparator configured to compare a first voltage with a threshold, the first voltage being equal, during a first period, to a first increasing ramp and, during a second period, to a second decreasing ramp, the threshold having a first value during the first period and a second value during the second period, the first and second values being variable.

Voltage converter and method

In an embodiment, a voltage converter includes: a first transistor coupled between a first rail configured to receive a supply voltage and a first node; and an inductance coupled between the first node and a second node configured to deliver an output voltage, wherein, at each operating cycle of the converter, the first transistor is maintained in the on state for a first time period proportional to the inverse of a voltage difference between the supply voltage and the output voltage.

Voltage converter

An embodiment voltage converter includes a first transistor and a second transistor coupled in series, and a first circuit configured to control the first and second transistors. The control terminal of the second transistor is coupled to a first output of the first circuit by a second circuit configured to delay the control signals supplied at the first output by a first duration. The control terminal of the first transistor is coupled to a second output of the first circuit by a circuit configured to delay the control signals supplied at the second output, for a second period of each operating cycle, by a duration equal to twice the first duration and, during a second period of each operating cycle, by a duration equal to the first duration.

A method for increasing performance of a voltage-buck switched-mode voltage regulator includes generating a first pulse-width modulation signal based on a clock signal, decreasing a frequency of the clock signal to form a modified clock signal, passing the modified clock signal to a digital modulation circuit as a regulated clock signal; and generating a second pulse-width modulation signal based on the regulated clock signal using the digital modulation circuit. The first pulse-width modulation signal includes a period Tand an off duration Dcorresponding to a first duty cycle. The off duration Dis an intrinsic pulse-width modulation signal generation latency. The second pulse-width modulation signal includes a period Tand the off duration D. The decreased frequency of the modified clock signal causes Tto be greater than Tsuch that a second duty cycle of the second pulse-width modulation signal is increased relative to the first duty cycle.

Method of adjusting a pulse width modulation signal

In an embodiment, a voltage comparator includes: a first switch having a conduction terminal coupled to an internal node that is coupled to an output of the voltage comparator; a current source; a capacitor; and a second switch connected in parallel with the capacitor, wherein the current source, the capacitor, and the first switch are coupled in series.

Voltage comparator

In an embodiment, a method for operating a voltage step-down switched mode power supply includes delivering an output voltage with an output stage having a power transistor that is cyclically made conducting by a first control signal. In PWM mode, the method includes generating an error voltage based on the output voltage and a reference voltage, and applying a first delay on a first control signal. The first delay is determined so as to reduce a difference between the error voltage and the reference voltage.

Method for operating a switched mode power supply of the buck type and corresponding switched mode power supply

In an embodiment, A device includes an operational amplifier and a feedback loop. The feedback loop is coupled between a first input of the operational amplifier and an output of the operational amplifier. The feedback loop is controllable according to a saturation of the operational amplifier. In one example, the device is incorporated in a microcontroller.

Switched-mode power converter

A method can be used for regulating a pulse-width modulation signal that is driving a voltage-buck switched-mode voltage regulator. The method includes comparing an input voltage of the switched-mode voltage regulator with a threshold voltage. The frequency of the pulse-width modulation signal is decreased when the input voltage is lower than the threshold voltage. The frequency is not decreased when the input voltage is not lower than the threshold voltage.

A method includes switching a switching circuit of the switched-mode power supply in a synchronous mode by turning on and off switches of the switching circuit in synchrony with a clock signal, wherein the switching circuit is coupled to an inductive element, and wherein the synchronous mode comprises a charging phase and a discharging phase; switching the switching circuit in an asynchronous mode by turning on and off switches of the switching circuit without being synchronized with the clock signal, wherein the asynchronous mode comprises a charging phase and a discharging phase; charging the inductive element during the charging phase of the synchronous mode; discharging the inductive element during the discharging phase of the synchronous mode; charging the inductive element during the charging phase of the asynchronous mode; and discharging the inductive element during the discharging phase of the asynchronous mode.

SMPS and control process of a SMPS

A method for controlling operation of a comparator that includes an amplifier that is connected at an input of the comparator includes neutralizing any change of state of a signal output by the comparator starting from each moment in time at which the change of state of the output signal occurs and lasting for a duration of propagation to compensate for a duration of propagation of signals within the amplifier.

Non-oscillating comparator

A comparison circuit includes an input interface configured to receive input signals and an output interface configured to deliver an output signal. A comparator is coupled between the input interface and the output interface. An amplifier is coupled between the input interface and the comparator. A neutralization circuit is configured to neutralize any change of state of the output signal starting from each moment in time at which the change of state of the output signal occurs and lasting for a second duration of propagation that compensates for a duration of propagation of signals within the amplifier.

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Grenoble, France

David Chesneau