Abstract
Piezoelectric transducers are triggered by the output voltage signal of a transmit voltage amplifier (TVA). In mobile ultrasound instruments, the sensitivity of piezoelectric transducers is a critical parameter under limited power supply from portable batteries. Therefore, the enhancement of the output voltage amplitude of the amplifier under limited power supply could increase the sensitivity of the piezoelectric transducer. Several-stage TVAs are used to increase the voltage amplitude. However, inter-stage design issues between each TVA block may reduce the voltage amplitude and bandwidth because the electronic components of the amplifier are nonlinearly operated at the desired frequency ranges. To compensate for this effect, we propose a novel inter-stage output voltage amplitude improvement (OVAI) circuit integrated with a class-B TVA circuit. We performed fundamental A-mode pulse-echo tests using a 15-MHz immersion-type piezoelectric transducer to verify the design. The echo amplitude and bandwidth when using an inter-stage OVAI circuit integrated with a class-B TVA circuit (696 mVPP and 29.91%, respectively) were higher than those obtained when using only the class-B TVA circuit (576 mVPP and 24.21%, respectively). Therefore, the proposed OVAI circuit could be beneficial for increasing the output amplitude of the class-B TVA circuit for mobile ultrasound machines.
Highlights
Piezoelectric transducers are used to generate very weak acoustic waves or electrical signals as energy sources owing to high signal loss [1,2,3]
Compared with the piezoelectric transducers used in desktop ultrasound machines, the piezoelectric transducers used in mobile ultrasound machines suffer from a lower sensitivity due to the smaller size of the piezoelectric material resulting from the limited portable battery and closed structures of these machines
A several-stage transmit voltage amplifier (TVA) must be constructed to increase the voltage generation in order to improve the sensitivity of piezoelectric transducers
Summary
Piezoelectric transducers are used to generate very weak acoustic waves or electrical signals as energy sources owing to high signal loss [1,2,3]. Compared with the piezoelectric transducers used in desktop ultrasound machines, the piezoelectric transducers used in mobile ultrasound machines suffer from a lower sensitivity due to the smaller size of the piezoelectric material resulting from the limited portable battery and closed structures of these machines. Smaller-sized materials need to be utilized to fabricate piezoelectric transducers in order to obtain stable performances due to heat generation. When the amplifier devices are connected in series, several electrical performance issues, such as input/output impedances, maximum voltage swings, and current dissipation, occur [12,13,14]. These issues directly affect the performance of the ultrasound components
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
