Build Your 24 Volt 3 Amp Power Supply Circuit

Description

This stabilized power source is adjustable, ranging from 3 to 25 volts, and its current flow is limited to 2 amps as depicted, although it can be elevated to 3 amps or greater by employing a smaller current sensing resistor (0.3 ohm). The 2N3055 and 2N3053 transistors must be affixed to appropriate heat sinks, and the current sensing resistor should possess a power rating of at least 3 watts. Voltage stabilization is governed by half of a 1558 or 1458 operational amplifier. The 1458 may be utilized as a replacement in the schematic below, however, it is advised that the supply voltage to pin 8 be constrained to 30 VDC, which can be achieved by adding a 6.2 volt zener diode or a 5.1 K resistor in series with pin 8. The highest DC supply voltage permitted for the 1458 and 1558 is 36 and 44 respectively. The power transformer is required to deliver the desired current while maintaining an input voltage no less than 4 volts above the target output, yet not surpassing the maximum supply voltage of the op-amp under minimal load circumstances.

Operational Amplifiers

Operational amplifiers (op-amps) are integrated circuits designed to amplify small electrical signals. They are fundamentally building blocks in countless electronic circuits. The 1558 and 1458 series op-amps, frequently employed in this circuit, are dual-supply versions, offering both positive and negative voltage rails. These ICs are characterized by their high gain, enabling them to amplify even minuscule current variations into significant voltage changes. The 1558 and 1458 op-amps feature several input terminals, including inverting, non-inverting, and sometimes differential inputs, providing flexibility in signal conditioning and amplification configurations. Typical applications include voltage regulation, audio amplification, and instrumentation. These op-amps are crucial for the precise control of the power supply’s output voltage.

Circuit diagram