Patent Number: 6,885,172

Title: Device for driving a power transistor of a voltage converter provided with a piezoelectric transformer and corresponding voltage converter

Abstract: A driving device is provided for driving at least one power transistor of a voltage converter that includes a piezoelectric transformer. The power transistor has a first non-drivable terminal coupled to an input voltage and to the input of the piezoelectric transformer. The converter includes an inductor coupled between the input voltage and the piezoelectric transformer, and a resistor coupled between a second non-drivable terminal of the power transistor and ground. The driving device is coupled to the drivable terminal of the power transistor, to the input of the piezoelectric transformer, and to the second non-drivable terminal of the power transistor so as to detect a first voltage value and a second current value. The driving device is adapted to cause the turning on of the power transistor if the first voltage value is equal to a third prefixed voltage value, and to cause the turning off of the power transistor if the second current value is equal to a fourth prefixed current value.

Inventors: Danioni; Alberto (Pavia, IT), Ricotti; Giulio (Broni, IT)

Assignee: STMicroelectronics s.r.l.

International Classification: H01L 41/00 (20060101); H02M 3/04 (20060101); H02M 3/156 (20060101); H01L 41/04 (20060101); G05F 001/10 (); G05F 001/656 ()

Expiration Date: 04/26/2022