Abstract: A transient noise detection circuit for detecting a level of a transient noise voltage is disclosed. The transient noise detection circuit comprises a triggering circuit, a rectifying circuit, and a controller. The triggering circuit is coupled between a power rail and a ground node. When the triggering circuit receives a transient noise, the triggering circuit generates a triggering signal. The rectifying circuit comprises a rectifying unit and a current-limiting unit coupled in series. When the rectifying unit receives the triggering signal from the triggering circuit, the rectifying unit will be triggered by the triggering signal. The controller is coupled to a detection node between the rectifying unit and the current-limiting unit. The controller is used for determining the level of the transient noise voltage based on the voltage of the detection node.