Hysteresis circuit, emergency lighting circuit and lighting device

Abstract

The present disclosure discloses a hysteresis circuit, an emergency lighting circuit, and a lighting device. The hysteresis circuit includes a voltage detection module, an isolation coupling module, and a voltage adjusting module. By detecting the sampling voltage associated with the input voltage, in the case that the sampling voltage is detected to decrease to the trigger action voltage point, the corresponding level of the output signal flips until it is detected that the sampling voltage rises to the reverse recovery voltage point, and the corresponding level of the output signal is controlled to flip again, thus achieving timely and accurate judgment of input voltage status.