Abstract: It is required that large amounts of data would be stored in time for further processing and analysis when ultrasonic signals are sampled. For the limitation of the access speed of memory chips, in some cases, the digital signals can not be stored totally at high sampling rate, thus the access speed of the memory becomes the bottleneck for improving the sampling rate. Several techniques for high speed buffer circuits are discussed. SN74V293, the FIFO memory produced by TI, is used to buffer the sample data in the design of a digital ultrasonic instrument. This circuit meets the requirements of the most ultrasonic NDT application.