+50V 3A adjustable power supply - Power Circuit - Circuit Diagram

This circuit is designed to provide an output ranging from +40V to +60V at 3A, with simultaneous stabilization. The components used are quite basic and shouldn't pose any significant challenges during manufacturing, provided you pay attention to certain details.

1. For output voltages between +50V and +40V, transistor Q1 tends to get quite hot, so it requires a large heat sink.
2. In this circuit, the potentiometer RV1 is used to adjust the output voltage between +40V and +70V. However, after finalizing the adjustment, it might be better to replace it with two fixed resistors to stabilize the output voltage, which could vary by up to 3V over time due to the potentiometer. Be cautious! The positive output corresponds to point [A], while the 0V output corresponds to point [B]. These should not be connected to the ground.

Parts List

• R1 = 10kΩ
• R8 = 1.8kΩ, 0.5W
• Q3 = BC303 or BC461
• R2 = 1Ω, 5W
• R9 = 3.3kΩ, 0.5W
• D1-4 = Bridge 15A
• R3 = 3.9Ω, 1W
• RV1 = 470Ω potentiometer
• D5 = RED LED, 5mm
• R4 = 6.8kΩ, 1W
• C1-2-4 = 4700µF, 100V
• D6-7 = 10V, 1W Zener diode
• R5 = 390Ω, 1W
• C3-5 = 100nF, 250V MKT
• D8-9-10 = 1N4007
• R6 = 100kΩ, 0.5W
• Q1 = 2N3055 on heatsink
• T1 = 230Vac / 55V, 3A
• R7 = 1.2kΩ, 1W
• Q2 = BD162 or BD243 or BD543