Efficient high voltage pulser for piezoelectric air coupled transducer

Linas Svilainis; Andrius Chaziachmetovas; Vytautas Dumbrava

doi:10.1016/j.ultras.2012.06.004

Efficient high voltage pulser for piezoelectric air coupled transducer

Ultrasonics. 2013 Jan;53(1):225-31. doi: 10.1016/j.ultras.2012.06.004. Epub 2012 Jun 16.

Authors

Linas Svilainis¹, Andrius Chaziachmetovas, Vytautas Dumbrava

Affiliation

¹ Signal Processing Department, Kaunas University of Technology, Studentu Str. 50, LT-51368 Kaunas, Lithuania. linas.svilainis@ktu.lt

PMID: 22742963
DOI: 10.1016/j.ultras.2012.06.004

Abstract

The design of high voltage pulser for air coupled ultrasound imaging is presented. It is dedicated for air-coupled ultrasound applications when piezoelectric transducer design is used. Two identical N-channel MOSFETs are used together with 1200V high and low side driver IC. Simple driving pulses' delay and skew circuit is used to reduce the cross-conduction. Analysis of switch peak current and channel resistance relation to maximum operation frequency and load capacitance is given. PSPICE simulation was used to analyze the gate driver resistance, gate pulse skew, pulse amplitude influence on energy consumption when loaded by capacitive load. Experimental investigation was verified against simulation and theoretical predictions. For 500pF capacitance, which is most common for piezoelectric air coupled transducers, pulser consumes 650μJ at 1kV pulse and 4μJ at 50V. Pulser is capable to produce up to 1MHz pulse trains with positive 50V-1kV pulses with up to 10A peak output current. When loaded by 200kHz transducer at 1kV pulse amplitude rise time is 40ns and fall time is 32ns which fully satisfies desired 1MHz bandwidth.