Stmicroelectronics S.r.l.

Giovanni Caggegi

Francesco Pulvirenti

Giuseppe Cantone

Vincenzo Marano

Fabrizio Bognanni

Vincenzo Palumbo

A circuit includes a current path and a negative bootstrap circuitry coupled to the current path. The current path is coupled between a floating voltage and a reference ground, and includes a current generator coupled through a resistor to the floating voltage at a first node of the current generator. The current generator is controlled by a pulse signal. The negative bootstrap circuitry includes a pump capacitor coupled to a second node of the current generator and to the reference ground. The pump capacitor is configured to provide a negative voltage at the second node of the current generator based on the pulse signal.

Circuit to transfer a signal between different voltage domains and corresponding method to transfer a signal

A circuit provides a high-voltage low-drop diode-like conductive path between a DC voltage supply terminal and a bootstrap terminal in charging a supply capacitor for driving a power switch with the capacitor set between the bootstrap terminal and an output terminal alternatively switchable between a low voltage and a high voltage DC voltage. In an embodiment, the circuit includes first and second transistors such as LDMOS depletion transistors with the first transistor set in a cascode arrangement between the bootstrap terminal and the DC voltage supply terminal and the second transistor coupled with a sense comparator for comparing the voltage at the bootstrap terminal with the voltage at said DC voltage supply terminal. The first and second transistors have common control terminals coupled with the DC voltage supply terminal and common coupling terminals to the bootstrap terminal.

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Cornaredo, Italy

Giovanni Caggegi