Microchip Technology Inc.

Micrel, Incorporated

Stmicroelectronics S.r.l.

Maxim Integrated Products, Inc.

Paolo Nora

Alex Hsu

Sam Tung Tsui

Charles Vinn

Marco Passoni

Marcello Criscione

Ioan Stoichita

Tsz Yin Man

Bruce C Larson

Federico Piccitto

Gabriele Sassone

Enrico Dallago

Charles A Casey

Various embodiments relate to a voltage converter including a control unit configured for operating in a hysteretic control mode. A control unit may be configured to receive a PWM signal, a duty cycle signal, at least one reference voltage, a factor of an output voltage of the voltage converter, and a factor of an input voltage of the voltage converter. The control unit may also be configured to compare the at least one reference voltage to the factor of the output voltage and the factor of the input voltage. Further, the control unit may be configured to generate a first control signal mirroring the PWM signal in response to at least one of: the factor of the input voltage being greater than the at least one reference voltage and the factor of the output voltage being greater than the at least one reference voltage. The control unit may also be configured to generate a second, different control signal including a low logic signal in response to the factor of the input voltage being less than or equal to the at least one reference voltage.

Voltage converters with hysteretic control

A switch mode power supply (voltage converter) is adapted as a current-mode control buck regulator for different loading conditions. The voltage converter operates in a continuous conduction mode (CCM) during heavy load conditions using pulse width modulation (PWM). When a zero-current detector determines no inductor current during light load conditions (discontinuous conduction mode (DCM) region), the controller initiates adaptive duty control using pulse frequency modulation (PFM). Adaptive duty estimation circuitry provides controllable energy to charge the power inductor to maintain voltage accuracy and maximize efficiency when in the PFM mode. Using clock synchronization and a single control-loop, smooth transition between PFM, PWM, and bypass modes is automatically performed. Clock synchronization from a master oscillator provides a base for frequency division in different operation modes which gives controllable evenly distributed switching harmonics. An inductor zero-current detector triggers an adaptive estimated duty cycle that is synchronized with the master oscillator.

Enhanced switching regulator topology with adaptive duty control and seamless transition of operating modes

A switching regulator using current mode control and adaptive slope compensation includes a DC correction circuit to introduce a DC correction signal to cancel the DC offset error generated by the slope compensation signal. In some embodiments, the DC correction signal is a function of the input voltage and the output voltage and is applied in response to the slope compensation signal being applied. In one embodiment, the DC correction signal is a linear function of the input voltage and the output voltage.

Switching regulator using adaptive slope compensation with DC correction

A power system for providing an output current at a regulated system output voltage includes a first power stage and a second power stage, each being a constant on-time (COT) controlled power converter. The first and second power stages generate respective first and second regulated output voltage having reduced or very small output ripple at a common output voltage node. The first and second power stages each includes a ripple injection circuit to inject a ripple signal to the feedback control circuit in each power stage. The power system further includes a current sharing control circuit configured to measure a first output current of the first power stage and a second output current of the second power stage, and to generate a control signal to modulate the feedback control circuit of the second power stage to force the second output current to equal to the first output current.

Current sharing method for COT buck converter

An apparatus, such as a Buck converter system, for generating an output voltage while at the same time monitoring whether an overload or over current condition occurs at the output, and protecting the system if the overload or over current condition occurs. The apparatus includes a first circuit adapted to monotonically change a control voltage from a first voltage (e.g., approximately ground potential) towards a second voltage (e.g., a reference voltage V); a second circuit adapted to generate the output voltage based on the control voltage; a third circuit adapted to detect whether a magnitude of an output current exceeds a current threshold; and a fourth circuit adapted to change the control voltage from the second voltage towards the first voltage in response to the third circuit detecting that the magnitude of the output current exceeds the current threshold.

System and method of controlling the soft start control voltage of switching regulator in response to output current sensing

A modular power supply system includes DC&mdash;DC converters connected n parallel and functioning in a PWM mode. The modular power supply system controls current sharing among the DC&mdash;DC converters using a single wire current sharing control bus that drives in parallel the inputs of all the DC&mdash;DC converters. The output of each DC&mdash;DC converter is applied to a logic OR circuit. Each converter has an identical logic circuit between its output and the single wire current sharing control bus.

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Belgioioso, Italy

Paolo Nora