Patent attributes
The present invention describes a modulator including a differential amplifier connected to a reference voltage and a first transistor, and the first transistor is connected to a feedback device, and a second transistor is set between the first transistor and the differential amplifier and connected to a voltage detector and a diode, and the diode is connected to a power supply, and the voltage detector keeps on detecting an output voltage (VOUT) between the feedback device and the first transistor. If the output voltage (VOUT) value is lower than a predetermined voltage value of the power supply, the voltage detector will issue a signal to drive the second transistor and limit a gate-source voltage (VGS) of the first transistor within a voltage difference of the diode, so as to reduce the impetus of the first transistor and avoid the phenomenon of a sudden climb with an excessively large output voltage (VOUT).
