An Integrated Operational Transconductance Amplifier Design for Doppler Ultrasound System

• Main Authors: Kun-Chu Lee, 李昆築
• Other Authors: Chin Hsia
• Format: Others
• Language: zh-TW
• Published: 2018
• Online Access: http://ndltd.ncl.edu.tw/handle/w9g7n5

碩士 === 國立中央大學 === 電機工程學系 === 106 === In recent years, the global aging has driven the development of the therapeutic and auxiliary medical device market, especially the use of home care, such as blood glucose meters, blood pressure monitors, etc. Therefore, it is very important to develop care equipment with mobility, miniaturization, and low power consumption. This paper presents the design of the probe driving circuit in Doppler ultrasound system for blood flow sensing, which is an operational- transconductance-amplifier(OTA) with high current, high linearity, and low power consumption. Three circuit architectures are presented, namely conventional OTA architecture, complementary OTA architecture, and OTA with slew rate enhancer. The circuits in this paper are designed and implemented with an integrated circuit. They were fabricated in VIS 0.5μm SOI 2P4M 5V CMOS process. The supply voltage is 5V, and the load capacitor is 2nF. The area of complementary OTA architecture is 850*560µm2. The area of OTA with slew rate enhancer is 812.5*532.07μm2. The IC measurement achieves 5MHz sine wave signal and 10MHz sine wave signal, respectively. The slew-rate is 68V/μs and 100V/μs, and the static power consumption is 140mW and 48mW, respectively. For the large capacitive load of ultrasound probes, using the architectures proposed in this paper to drive can reduce the overall system power consumption. The development of miniaturized, wearable or mobile medical products for battery-powered can extend the life cycle, and the stability can be greatly improved.