Adjustable voltage comparing circuit and adjustable voltage examining device

摘要

In an adjustable voltage examining module, while a logic tester issues an input signal to an audio module under test, upper/low-threshold reference signals are simultaneously issued to an adjustable voltage comparing circuit. While the adjustable voltage comparing circuit receives a signal under test returned by the to-be-examined audio module after a while, the adjustable voltage comparing circuit loads both an high-threshold reference voltage and a low-threshold reference voltage respectively indicated by the reference upper/low-threshold signal so as to compare both the upper and low-threshold reference voltages with the signal under test. Therefore, while the signal under test is examined to acquire a voltage level between voltage levels of the upper and low-threshold reference signals, precise operations of the audio module under test are assured, and time wasted by continuously-issued interrupt is saved.