Ultrasound meter for measuring the liquid flowrate has means for balancing or reducing the effect of the comparator offset voltage so that accurate measurements can still be made when the measurement voltage is of the same order

摘要

Method for operation of an ultrasound meter (1) using a comparator (2) for flank detection of sinusoidal voltage signals from an ultrasound transducer. The comparator has a first input for a measurement signal from the transducer (Ue) and a second input for a reference voltage (Uref). To balance or reduce the comparator offset voltage a voltage is added to the reference voltage input that balances or reduces the offset voltage. Independent claims are included for: (1) a corresponding comparator circuit; (2) an ultrasound meter.