Patent ID: 6680603
Filing Date: 2004-01-20
Classification: H02M

Abstract:
An ultrasonic position sensor having a high-efficiency pulse generator for generating short voltage pulses, comprising:a voltage converter which has a first switch, a second switch, an inductor and a storage capacitor, wherein the first switch is actuatable to enable current pulses in the inductor, which pulses are fed to charge the storage capacitor to generate an output voltage; a pulse regulator which generates control pulses that are influenced by a voltage derived from the output voltage, actuating the first switch when said output voltage falls below a lower limit value, until the output voltage has reached an upper limit value greater than or equal to the lower limit value; an ultrasonic sensor exciter circuit having an inductive component; and an output side switch including a first load switch, said output side switch having a first switching mode during which said first load switch is switched on and voltage at the storage capacitor is fed through said first load switch to the ultrasonic sensor exciter circuit in the form of a discrete voltage pulse, and a second switching mode, during which said first load switch is switched off, isolating the ultrasonic sensor exciter circuit from the voltage at the storage capacitor so that no voltage pulse is fed to the ultrasonic exciter circuit, and self induction energy from the ultrasonic exciter circuit is returned to the storage capacitor.