The working principle of a regulated power supply is based on a negative feedback mechanism. When the input voltage or load changes, the output voltage will fluctuate accordingly. At this point, the feedback circuit will collect the fluctuation signal of the output voltage and send it to the comparison circuit for comparison. The comparison circuit compares the feedback signal with the reference voltage and generates an error signal. After amplification, this error signal is sent to the control terminal of the output circuit to adjust the adjustable resistors or other components in the output circuit, thereby changing the output voltage and restoring it to a stable value.
Specifically, as the input voltage increases, the output voltage also increases. At this point, the feedback signal collected by the feedback circuit will be higher than the reference voltage, and the comparison circuit will generate a negative error signal. After amplification, this negative error signal is sent to the control terminal of the output circuit, which increases the adjustable resistance in the output circuit and reduces the output voltage. On the contrary, when the input voltage decreases, the output voltage will also decrease. At this point, the feedback signal collected by the feedback circuit will be lower than the reference voltage, and the comparison circuit will generate a positive error signal. After amplification, this positive error signal is sent to the control terminal of the output circuit, reducing the adjustable resistance in the output circuit and thereby increasing the output voltage.
