Stmicroelectronics Design and Application S.r.o.

Stmicroelectronics S.r.l.

Stmicroelectronics International N.v.

Sandor Petenyi

Marco Pasotti

Fabio De Santis

Calogero Ribellino

Dario Livornesi

Roberto Bregoli

Lukas Buryanec

Federico Musarra

An electronic device includes multiple integrated circuits, each containing a power transistor connected between an input voltage node and a load node, as well as a regulation circuit generating at least one sense current representing the output current of the power transistor. The regulation circuits modulate the output currents of their power transistors based on a value derived from the sense currents generated by the regulation circuits of other integrated circuits. This derived value can be based on an average of the sense currents generated by the regulation circuits or on one of the sense currents. In particular, the integrated circuits can be arranged in a daisy-chained relationship, allowing each regulation circuit to compare its sense current with the one from the immediately preceding circuit, except for the first regulation circuit, which compares its sense current with the last circuit's sense current in the chain.

Current balancing in parallel configuration of multiple power devices

A power circuit includes a power transistor coupled between input and output nodes and receiving a control signal. A current sensing current senses a power current provided by the power transistor to the output node and generates a sense voltage. A voltage sensing circuit senses a drain-to-source voltage of the power transistor and generates a VDS sense current. A safe operating area (SOA) shaping circuit has a gain set by an adjustable resistance that is dynamically adjusted based upon the VDS sense current, the SOA shaping circuit applying the gain to the sense voltage to produce an adjusted sense voltage. A timing circuit generates an intermediate voltage by comparing the adjusted sense voltage and a first reference. An output comparator asserts a flag in response to the intermediate voltage becoming at least equal to a second reference. The control signal is modified in response to assertion of the flag.

SOA protection of a power transistor

A MOSFET has a current conduction path between source and drain terminals. A gate terminal of the MOSFET receives an input signal to facilitate current conduction in the current conduction path as a result of a gate-to-source voltage reaching a threshold voltage. A body terminal of the MOSFET is coupled to body voltage control circuitry that is sensitive to the voltage at the gate terminal of the MOSFET. The body voltage control circuitry responds to a reduction in the voltage at the gate terminal of the MOSFET by increasing the body voltage of the MOSFET at the body terminal of the MOSFET. As a result, there is reduction in the threshold voltage. The circuit configuration is applicable to amplifier circuits, comparator circuits and current mirror circuits.

Circuit employing MOSFETs and corresponding method

A circuit includes a current controller oscillator generating a CCO output signal at a CCO output, a charge pump boosting a supply voltage based on the CCO output signal and producing a charge pump output voltage at an output, and a current sensing circuit sensing load current at the output and generating a feedback signal having a magnitude that varies with the sensed load current if a magnitude of the sensed load current is between lower and upper load current thresholds. A frequency of the CCO output signal is constant at a lower frequency threshold where the sensed load current is below the lower load current threshold, asymptomically rises to an upper frequency threshold where the sensed load current is above the upper load current threshold, and is proportional to the feedback signal where the sensed load current is between the lower and upper load current thresholds.

Charge pump with load driven clock frequency management

A circuit includes a current controlled oscillator (CCO), and a charge pump circuit boosting a supply voltage to produce a charge pump output voltage at a charge pump output node in response to output from the CCO. A current sensing circuit includes a first resistor coupled between the charge pump output node and an output node, a first transistor having a first conduction terminal coupled to the charge pump output node through a second resistor, and a second conduction terminal coupled to an input of the CCO. A second transistor has a first conduction terminal coupled to the output node, a second conduction terminal coupled to a reference current source, and a control terminal coupled to the control terminal of the first transistor and to the second conduction terminal of the second transistor.

An amplifier stage of an LDO regulator circuit includes an amplifier stage that generates a drive signal in response to a first voltage difference an output voltage of the LDO regulator circuit and a reference voltage. A drive stage having a quiescent current consumption is configured to generate a control signal in response to the drive signal. The control signal is applied to the control terminal of a power transistor. A dropout detector senses whether the LDO regulator circuit is operating in closed loop regulation mode or in open loop dropout mode by sensing a second difference in voltage between the drive signal and the control signal. A quiescent current limiter circuit responds to the sensed second difference by controlling the quiescent current consumption of the drive stage, and in particular limiting current consumption when the LDO regulator circuit is operating in the open loop dropout mode.

Voltage regulator with controlled current consumption in dropout mode

A charge pump circuit has load driven clock frequency management. The charge pump circuit includes a CCO generating a CCO output signal that has a frequency generally proportional to a feedback current, and a charge pump operated by the CCO output signal and boosting a supply voltage to produce a charge pump output voltage at an output coupled to a load. A current sensing circuit senses a load current drawn by the load and generates the feedback current as having a magnitude that varies as a function of the sensed load current if a magnitude of the load current is between a lower load current threshold and an upper load current threshold. The magnitude of the feedback current does not vary with the sensed load current if the magnitude of the sensed load current is not between the lower load current threshold and the upper load current threshold.

In an embodiment, a current sense circuit includes a copy transistor having a gate configured to be coupled to a gate of an output transistor, and a drain coupled to an input terminal. The drain of the copy transistor is configured to be coupled to a drain of the output transistor. A first transistor has a current path coupled to a current path of the copy transistor. An error amplifier has a non-inverting input coupled to a source of the copy transistor, an inverting input configured to be coupled to a source of the output transistor, an output coupled to a gate of the first transistor, a positive power supply terminal coupled to the input terminal and a negative power supply terminal coupled to a reference supply terminal. A current-to-voltage converter has an input coupled to the current path of the copy transistor.

Current sensor with extended voltage range

A voltage regulator having bias current boosting is provided. The voltage regulator includes a power stage for providing an output voltage to a load. The voltage regulator includes a differential stage that receives a feedback voltage representative of the output voltage and a reference voltage and controls the power stage based on a difference between the reference voltage and the feedback voltage. The voltage regulator includes a bias current boosting stage that receives the feedback and reference voltages. The bias current boosting stage provides a boosted bias current having a current level that is based on the difference between the reference and feedback voltages. The boosted bias current biases the differential stage and hastens a response of the differential stage, in response to a change in the difference between the reference voltage and the feedback voltage, in controlling the power stage.

Voltage regulator having bias current boosting

A significant reduction of the amplitude of the transient response is obtained by keeping a low dropout regulator circuit in a closed loop condition. This is achieved by manipulation of the reference voltage level when an open loop condition arises due to a falling input voltage. In this case, the reference voltage level is tracked with the input voltage level, keeping the output voltage regulated. As a consequence, the power pass element of the regulator is not forced into the linear region (in the case of a MOSFET) or deep saturation (in the case of a bipolar transistor).

Voltage regulator with improved line regulation transient response

A voltage regulator is controlled to improve supply voltage rejection by cancelling an alternating component of a supply voltage signal that is capacitively coupled to a high-impedance node within the voltage regulator. This cancellation is done by capacitively coupling an inverted version of the alternating component to the high-impedance node to thereby substantially cancel the alternating component present on the high-impedance node. The high-impedance node may be a high-impedance voltage reference node of the voltage regulator.

Voltage regulator circuits, systems and methods for having improved supply to voltage rejection (SVR)

A device for generating a reference voltage includes a first non-volatile memory cell provided with a control-gate transistor and a reading transistor. The control-gate transistor includes a gate terminal, a body, a first conduction terminal and a second conduction terminal. The first conduction terminal and the second conduction terminal are connected together to form a control-gate terminal. The reading transistor includes a gate terminal that is connected to the gate terminal of the control-gate transistor to form a floating-gate terminal, a body, a third conduction terminal and a fourth conduction terminal. The device also includes a second, equivalent, memory cell. The source terminal of the first non-volatile memory cell and the source terminal of the second equivalent memory cell are connected together.

Device for generating a voltage reference comprising a non-volatile memory cell

A voltage regulator includes an input terminal to receive an input voltage, an output terminal to supply an output voltage, a power transistor, a differential amplifier, a driver, a dropout detector and a bias current limiter. The differential amplifier provides a drive signal based on a difference between a voltage reference and a feedback signal corresponding to the output voltage. The driver includes an impedance device, and a driver transistor that receives the drive signal so as to vary a bias current to a control terminal of the power transistor. The dropout detector and the bias current limiter is coupled to the input terminal, the impedance device, and the output terminal and includes first and second transistors coupled together, and a bias current generator coupled to the second transistor.

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Lysa nad Labem, Czechia

Sandor Petenyi