摘要 |
A Universal Series Bus USB port detection and testing circuit, configured to detect the voltage output of a USB port of an electronic device, includes a voltage comparing circuit and an indicating circuit. The indicating circuit is connected to an output terminal of the voltage comparing circuit. The voltage comparing circuit compares the voltage output from the USB port against a reference voltage and output a signal whereby the indicating circuit indicates whether the voltage is within, or above, or below, the standard range. |