摘要 |
PURPOSE: An alternating current detection circuit for power supply is provided to reduce the cost by reducing the number of components used in the detection circuit by detecting the alternating current using a shunt regulator and a PNP transistor. CONSTITUTION: A voltage divider(200) divides the voltage rectified by a rectifier(100) into the set voltage. A voltage stabilization circuit unit(300) stabilizes the voltage partitioned by the voltage divider. A shunt regulator(400) compares the input voltage stabilized by the voltage stabilization circuit and the internal voltage reference. |