Stmicroelectronics S.r.l.

Alberto Cattani

Alessandro Gasparini

Stefano Ramorini

Alessandro Bertolini

Germano Nicollini

Pierangelo Confalonieri

Federico Guanziroli

Giuseppe Calcagno

Giuseppina Sapone

Massimo Antonio Ghioni

Eugenio Miluzzi

Salvatore Levantino

Marco Attanasio

Mauro Leoncini

Marco Pinsero

Tommaso Rosa

Federica Papotti

Claudio Luise

A DC-DC boost converter includes an input receiving an input voltage and an output producing an output voltage. A switching stage is formed by a low-side transistor arranged between a switching node and a ground node, and a high-side transistor arranged between the switching node and the output. The high-side transistor includes a body diode having an anode coupled to the switching node and a cathode coupled to the output. The converter is controlled in an asynchronous operation mode where the low-side transistor is driven alternately to a conductive state and a non-conductive state, and the high-side transistor is driven steadily to a non-conductive state. A variable load circuit is selectively coupled between the two output terminals when the converter is in the asynchronous operation mode in order to sink a load current having a value that is a function of a value of the input voltage.

DC-DC converter circuit, corresponding method of operation and method of trimming a DC-DC converter circuit

A switching DC-DC converter circuit includes a switching stage having an input node receiving an input voltage and an output node producing an output voltage. The converter includes feedback loop circuitry coupled to the output node of the switching stage to produce, at a respective output node, a control signal of the converter circuit as a function of a difference between the output voltage and a reference voltage. The converter includes test loop circuitry arranged between an output node of the feedback loop circuitry and the output node of the switching stage. The test loop, when enabled, sources a current to the output node of the switching stage or sinks a current from the output node of the switching stage as a function of a value of the control signal of the converter circuit. The feedback loop circuitry is calibrated during a test phase of the switching DC-DC converter circuit.

DC-DC converter circuit and corresponding method of testing a DC-DC converter circuit

A supply node receives supply voltage and an output node provides a regulated output voltage to a load. A switching transistor is coupled between the supply and output nodes. The switching transistor is controlled by a drive signal generated by a control circuit to control switching activity. The control circuit includes circuitry to sense a feedback voltage indicative of the regulated output voltage and a comparator generating a comparison logic signal dependent on a comparison of the feedback voltage to a reference. A logic circuit generates a skip signal in response to the comparison logic signal. A counter generates a termination signal. Signal processing circuitry controls the switching activity by asserting the drive signal as a function of the skip signal and the termination signal.

Voltage regulator device

A half bridge converter is controlled by a circuit including a differential circuit receiving a reference signal and a feedback signal which is a function of an output signal from the converter. The half bridge includes hand and low side switches. A comparator generates a PWM signal for controlling the converter as a function of the duty cycle of the PWM signal in response to a signal at an intermediate node between the hand and low side switches and an output of the differential circuit. A gain circuit block coupled between the intermediate node and the input of the comparator applies a ramp signal to the input of the comparator which is a function of the signal at the intermediate node. A variable gain is applied by the gain circuit block in order to keep a constant value for the duty cycle of said PWM signal irrespective of converter operation.

Circuit for controlling converters, corresponding converter device and method

A first switch couples an input node receiving a main control signal for a main switching stage of a multi-phase converter to an output node delivering a secondary control signal for a secondary switching stage following actuation of the secondary switching stage. A second switch couples the output node to a capacitor during a time period of actuation/deactuation of the secondary switching stage. Current is sourced to the capacitor during the actuation time period or sunk from the capacitor during the deactuation time period. The sourced or sunk current may be generated proportional to the main control signal.

Circuit, corresponding multi-phase converter device and method of operation

A control circuit operates to control a switching stage of an electronic converter. The control circuit includes: first terminals providing drive signals to electronic switches of the switching stage; a second terminal receiving from a feedback circuit a first feedback signal proportional to a converter output voltage; and a third terminal configured to receive from a current sensor a second feedback signal proportional to an inductor current. A driver circuit provides the drive signals as a function of a PWM signal generated by a generator circuit as a function of the first and second feedback signals, a reference voltage and a slope compensation signal. A mode selection signal is generated as a function of a comparison between the input voltage and the output voltage. A feed-forward compensation circuit is configured to source and/or sink a compensation current as a function of a variation in the mode selection signal.

Control circuit for controlling a switching stage of an electronic converter, corresponding electronic converter device and method

In a control circuit for a switching stage of an electronic converter, a phase detector generates a drive signal in response to a phase difference between first and second clock signals. The first and second clock signals are generated by first and second current-controlled oscillators, respectively. An operational transconductance amplifier generates first and second control currents in response to a difference between a reference and a feedback of the electronic converter, with the first and second currents applied to control the first and second current-controlled oscillators. In response to a switching clock having a first state, a switching circuit applies first and second bias currents to the control inputs of the first and second current-controlled oscillators, respectively. Conversely, in response to the switching clock having a second state, the switching circuit applies the second and first bias currents to the control inputs of the first and second current-controlled oscillators, respectively.

Control circuit for an electronic converter, related integrated circuit, electronic converter and method

In an embodiment, a method includes: providing a voltage setpoint to a voltage converter; generating an output voltage at a voltage rail with the voltage converter based on the voltage setpoint; when the voltage setpoint is transitioning from a first voltage setpoint to a second voltage setpoint that has a lower magnitude than the first voltage setpoint, providing a first constant current to a first node coupled to a control terminal of an output transistor to turn on the output transistor, where the output transistor includes a source terminal coupled to a first terminal of a first resistor, and where a current path of the output transistor is coupled to the voltage rail; and turning off the output transistor after the output voltage reaches the target output voltage corresponding to the second voltage setpoint.

Discharge circuit and method for voltage transition management

In start-up, current is sourced by a current source to a first plate of a first capacitor while a second capacitor is maintained at zero charge. In a subsequent first operating phase, current is sourced to a first plate of the second capacitor while a second plate of the first capacitor is connected to the first plate of the second capacitor. At the end of the first operating phase, the first capacitor is discharged. In a subsequent second operating phase, current is sourced to the first plate of the first capacitor while a second plate of the second capacitor is connected to the first plate of the first capacitor. At the end of the second operating phase, the second capacitor is discharged. Steady state operation of the circuit involves an alternation of the first and second operating phases interleaved with transition phases where the first and second capacitors are discharged.

Signal generator circuit, corresponding device and method

A Single Input Dual Output converter includes a first switch coupling an input to a first inductor terminal, a second switch coupling a second inductor terminal to ground, a third switch coupling the second inductor terminal to a positive output, and a fourth switch coupling the first inductor terminal to a negative output. During time-shared control, the negative and positive outputs are independently served by conversion cycles. Each conversion cycle includes: a positive phase with a positive charge phase (closing only the first and second switches), followed by an additional phase (closing only the first and third switches for a given time duration), and followed by a positive discharge phase (closing only the third and fourth switches). Each conversion cycle further includes a negative phase with a negative charge phase (closing only the first and second switches) followed by a negative discharge phase (closing only the second and fourth switches).

Method for controlling a single input dual output DC-DC converter, corresponding converter and computer program product

Charge pump stages are coupled between flying capacitor pairs and arranged in a cascaded between a bottom voltage line and an output voltage line. Gain stages apply pump phase signals having a certain amplitude to the charge pump stages via the flying capacitors. A feedback signal path from the output voltage line to the bottom voltage line applies a feedback control signal to the bottom voltage line. Power supply for the gain stages is provided by a voltage of the feedback control signal in order to control the amplitude of the pump phase signals. An asynchronous logic circuit generates the switching drive signals for the gain stages with a certain switching frequency which is a function of a logic supply voltage derived from the voltage of the feedback control signal.

Charge pump circuit, corresponding device and method

A converter circuit includes first and second electronic switches coupled at an intermediate node, with an inductor coupled between the intermediate node and an output node. Switching drive control circuitry causes the first and the second electronic switch to switch between a conductive state and a non-conductive state. The drive control circuitry includes a first feedback signal path to control switching of the first and the second electronic switch as a function of the difference between a feedback signal indicative of the signal at the output node and a reference value. A second feedback signal path includes a low-pass filter coupled to the output node and configured to provide a low-pass filtered feedback signal resulting from low-pass filtering of the output signal. The second feedback signal path compensates the feedback signal as a function of the difference between the low-pass filtered feedback signal and a respective reference value.

Converter circuit, corresponding device and method

A control circuit for controlling switching operation of a switching stage of a converter includes a phase detector circuit that generates a pulse-width modulated (PWM) signal in response to a phase comparison of two clock signals. A first clock signal has a frequency determined as a function of a first feedback signal proportional to converter output voltage. A first transconductance amplifier generates a first current indicative of a difference between a reference voltage and the first feedback signal, and a second transconductance amplifier generates a second current indicative of a difference between the reference voltage and a second feedback signal proportional to a derivative of the converter output voltage. A delay line introduces a delay in the first clock signal that is dependent on the first and second currents as well as a compensation current dependent on a selected operational mode of the converter.

A switching converter includes a voltage conversion circuit providing an output voltage from an input voltage and a PWM voltage generated in response to first and second oscillating voltages. The input stage of a transconductor circuit provides an input reference current following a difference between a reference voltage and a voltage dependent on the output voltage and according to a transconductance, and an output stage for providing an output reference current from the input reference current. A phase shifter shifts an oscillating reference voltage according to the output reference current to obtain the first and second oscillating voltages. The transconductance is controlled in response to the input voltage resulting in a change of the input reference current. Compensation for that change is provided by subtracting a variable compensation current from the input reference current, where the variable compensation current is generated in response to the input voltage.

Switching converter with adaptive compensation

Circuit, corresponding multi-phase converter device including a plurality of switching stages and method of operation for charging and discharging a capacitor dependent on switching stage operating transition

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Cislago, Italy

Alberto Cattani