Application of TDC-GP21 in ultrasonic flowmeter based on time difference method

In order to make the accuracy of ultrasonic flowmeter reach,the measurement principle of time-difference ultrasonic is studied,and the method to achieve high-precision measurements is analyzed.The system work process and hardware composition is introduced.The structure and principle of high-speed interval measuring chip TDC-GP21 as well as the hardware realization of ultrasonic measurement system is mainly elaborated.The high-precision measurement of ultrasonic downstream and upstream propagation time difference was achieved by using TDC-GP21,ARM microprocessor,ultrasonic transceiver circuit and other hardware architecture.The experiment result and accuracy analysis confirms that the ultrasonic flowmeter developed in this way can meet the design requirements.It provides a reference for high-accuracy and low-power design of ultrasonic flowmeter.