超音波系統的高壓脈衝發射器之過電流防護裝置

High Voltage Pulse Transmitter of Ultrasound Systems Overcurrent Protection Devices

呂冠毅(Kuan-Yi Lu)

指導教授 ： 陳自強

國立中正大學/工學院/電機工程學系/碩士(2015年)

摘要

隨著超音波領域的興盛，掃描儀產品需求量大增，使得高壓脈衝發射器的應用量大幅提高。為了減少預算成本、功率消耗及使用期限延長，目前許多保護功能已被提出。電流限制技術採用將負載電流與設定來源值比較，具有Push-Pull的高反應力、低功率消耗及面積小等優點。
本論文主要研究方向是利用電流限制的技術，以保護超音波高壓發射器產品之應用層面為考量，設計出利用電流限制電路輸出訊號以控制傳輸閘開關開啟與關閉之過電流保護裝置。此過電流保護裝置由電流鏡、電流限制電路、運算放大器(比較器)及傳輸閘開關所組成。保護裝置前端設計為電流鏡與電流限制電路，其可將要保護之電路的電流複製縮小與電流限制電路之值作比較，可使其輸出結果與需保護電路之電流是否過載有相應關係。另外，比較器將前端電流限制電路之輸出進行優化，使其通知後端訊號更為理想，最後藉由訊號通知傳輸閘開關進行開啟與關閉之動作。吾人所設計之過電流保護裝置採用台積電 TSMC 0.25μm 1P4M BCD 標準製程，進行電路設計模擬。佈局前模擬結果顯示過電流保護裝置消耗功率為6.67W。以上模擬結果驗證功能皆正確無誤，且已透過離散元件量測測試其結果。

關鍵字

電流鏡 ； 過電流保護 ； 高壓脈衝發射器 ； 電流限制電路 ； 傳輸閘開關

並列摘要

With increasing demand for the Ultrasound field of ultrasound scanner product greatly increased , so that the amount of applied high voltage pulse transmitter greatly improved. In order to reduce budget costs , power consumption and extended use , many protection functions have been proposed. Technology of Current limit uses the loading current compared with the set value reference, and has advantages of Push-Pull high reactivity , low power consumption and small size.
This thesis mainly utilizes current limiting technology and takes into consideration from protect the application level of high-voltage ultrasonic transmitter products. This overcurrent protection device designed by using current limit circuit output signal to control the transmission gate switch, which state on and off. This overcurrent protection includes current mirror, current limiting circuit, comparator design by operational amplifier and transmission gate switch. In this thesis, the protection of which front-end design has the current mirror and current limiting circuit, which can copy and reduce the current of be protected circuit. The current limit circuits output results can be find the corresponding relationship by comparing protected circuits current if it is overload. In addition, comparator output are optimized the output of front end current limit circuits, so that the backend is more ideal signals. Finally, using the signal notification the transmission gate switch to do the on and off action. The proposed overcurrent protection device has been use by the TSMC 0.25μm 1P4M BCD process, for circuit design and simulation. Pre-layout simulation results show that the overcurrent protection device power consumption is 6.67W. Simulation results verify the above functions are correct and have been measured to test their results through the amount of discrete components.

並列關鍵字

Transmission gate switch ； Current limit circuit ； Current mirror ； Over-current protection ； High voltage pulser

參考文獻

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