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Circuit Diagram

The LM10 integrated circuit is utilized here due to its inherent reference voltage functionality, which proves beneficial for constructing a direct current power supply. Employing two ICs enables the generation of diverse output voltages alongside adjustable current levels. This circuit incorporates protective measures against short-circuit conditions. P2 facilitates the control of the current within a range of 0 to 2 Amperes. The output voltage stability is achieved through resistor R4 connected to the negative terminal of the operational amplifier, and resistors R2 and P1 connected to the positive terminal.

Operational amplifier output controls transistor T1, preventing fluctuations in voltage. T1 can alter the amperage through resistor R6, controlling the voltage of transistors T5 and T4. Pin 1 serves as the reference voltage, with a small current (100uA) passing through resistor P1. This lost voltage, calculated as Vlose p1=100uA*Rp1, is utilized in regulating the output voltage rate, comparing it with the reference voltage provided by P3. Transistor T3 protects against short circuits using resistor R11. To reduce the output voltage to 0V, a 470-ohm resistor is paralleled in the output. The minimum allowable voltage is 0.4 volts, while the maximum output voltage is fixed by resistor R1b and should not exceed 50 volts. Consequently, a transformer providing 36 Volts, 3 Amperes, and incorporating a 4700uF capacitor is recommended. Transistors T6, T5, and T7 require heatsinks for effective heat dissipation.

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