The high efficiency and low ripple of linear stabilized power supply is one of its advantages. Through comparative analysis, this paper puts forward an improved scheme of using discrete components to design linear stabilized power supply. In this

scheme, the power frequency transformer is selected to realize the AC voltage conversion of 220V, and the bridge rectifier circuit

and capacitor filter circuit are selected to realize the rectification and filtering of the circuit. In the voltage stabilizing circuit, the sampling circuit samples through the sampling resistance; the reference voltage is provided by the TL431 and the voltage divider; the error amplification circuit is amplified by the LM358 dual operational amplifier and the voltage is adjusted by two power tubes.

Through the simulation of the final circuit and repeated debugging of the hardware, the continuous adjustable voltage from 220v input voltage to 0~20V output voltage is realized, and the current is stable at 1A output, and the ripple and differential voltage measured by the circuit are in line with the expected specifications.