Circuit arrangement for digitising and storing the maximum values of electrical ultrasonic pulses

摘要

A circuit arrangement for digitising and storing the maximum values of electrical pulses is described which is preferably used in ultrasonic test instruments for non-destructive testing of materials. The circuit arrangement (Figure 2) contains an analog/digital converter which operates in accordance with the parallel technique. In this technique, digitisation is effected with the aid of comparators (510) which are followed by D-type flip flops (530). The Q outputs of the D-type flip flops (530) are connected to the inputs of a priority encoder (540). To store the respective maximum value, the outputs of the D-type flip flops (530) are connected via OR gates (560) to the control inputs of the flip flops (530). The maximum binary value obtained at the output of the encoder (540) is transferred with the aid of an enable signal which is also generated by a logic combination of the outputs of the D-type flip flops (530) via AND gates (570). This enable signal is preferably used as a time reference value for a device measuring the delay time of ultrasonic pulses.