HYSTERESIS DETECTION METHOD, HYSTERESIS DETECTION CIRCUIT AND PORTABLE APPARATUS

摘要

A method and a circuit for detecting hysteresis, and a mobile device are provided to reduce power consumption by detecting the hysteresis irrespective of an initial input voltage. An input voltage(Vin) to be compared is inputted to a negative input terminal of a comparator circuit(3). When the compared input voltage is higher than a reference voltage, an output voltage(Vout) outputted from an output terminal of the comparator circuit is set to a low state. A switch(4) inputs a low reference voltage to a positive input terminal of the comparator circuit when the low output voltage is outputted from the output terminal. A hysteresis detecting circuit(1) is formed of low power consumption circuit elements. When the hysteresis detecting circuit is actuated, the compared input voltage is stabilized earlier than the reference voltages and is inputted to the comparator circuit.