A Fully-Printed Self-Biased Polymeric Audio Amplifier for Driving Fully-Printed Piezoelectric Loudspeakers

作者：Kheradmand Boroujeni Bahman^*; Schmidt Georg Cornelius; Hoeft Daniel; Bellmann Maxi; Haase Katherina; Ishida Koichi; Shabanpour Reza; Meister Tilo; Carta Corrado; Ghesquiere Pol; Huebler Arved C; Ellinger Frank

来源：IEEE TRANSACTIONS ON CIRCUITS AND SYSTEMS I-REGULAR PAPERS, 2016, 63(6): 785-794.

DOI：10.1109/TCSI.2016.2538060

• Amplifiers
• analog circuits
• audio systems
• flexible printed circuits
• loudspeakers
• OFETs
• organic thin film transistors
• polymer films

In this paper, a printed audio amplifier, which is a new application for organic electronics, is suggested. The amplifier consists of several fully-printed bendable components including: a loudspeaker, organic field effect transistors (OFETs), capacitors, and resistors. All components are fabricated on polyethylene terephthalate (PET) substrate by means of high-throughput printing techniques. A complete self-biased circuit is reported consisting of large multi-finger OFETs with channel length of 20 mu m and total width of 0.475 meter. The amplifier provides a peak voltage gain of 18 dB at 400 Hz, can reproduce sound pressure level of 36-60 dBA over 700 Hz to 12.5 kHz at one meter distance, and has a unity-gain-bandwidth of 17.7 kHz/5.2 kHz when driving 0 nF/similar to 39 nF load at V-DD = 80 V, respectively. The impact of bias-stress effects on the amplifier performance is measured to be similar to 3 dBA sound loss after 5 hours of continuous operation. The whole circuit is packaged and laminated on a separate PET sheet. In addition, the intrinsic electrical impedance of the printed PVDF-TrFE piezoelectric polymer used in the loudspeaker is characterized, and is modeled by a complex dielectric constant.

• 出版日期2016-6