Design of adjustable DC stabilized power supply circuit module

This circuit can realize an adjustable DC stabilized power supply through a simple circuit structure, and has a voltage indication, and the output DC voltage range is 0~30V.

Working principle of the circuit: This circuit adds 220V AC voltage to the primary side W1 through the transformer T, and obtains 35V and 6V AC voltages on the secondary side W2 and W3 respectively. The secondary side W2 terminal is rectified by the diodes VD1 ~ VD4 and the capacitor. After filtering, C1 and C2 are input to the input end of the IC three-terminal integrated voltage stabilizing circuit, and a 35V DC voltage is output through the IC voltage stabilizing integrated circuit, resistor R1 and capacitor C4. The 6V AC voltage output by the W3 coil on the secondary side outputs a negative voltage of -1.25V through the diode VD5, capacitor C3, resistor R2 and Zener diode VS as an auxiliary power supply. The rheostat RP is added to the control end of the IC integrated circuit. By adjusting the rheostat RP, the output end can output a DC power supply of 0~30V. The IC uses the LM317 three-terminal voltage stabilizing integrated circuit; R1 and R use 1/2W metal film resistors; C1 and C3 use aluminum electrolytic capacitors with withstand voltages of 50V and 10V respectively, and C2 and C4 use CD11-16V electrolytic capacitors; VD1 ~VD5 uses IN4007 silicon type rectifier diode; VS uses IN4106 or 2CW60 silicon voltage regulator diode; RP uses WSW type organic solid trimming variable resistor; T uses 10W power transformer with secondary side voltage of 35V and 6V.