Simple 0-24V/5Amp Variable Power Supply Circuit with Transistors

This 0-24V 5 Amp variable power supply circuit regulated mainly uses transistors for the power control and can be easily altered from 3 to 24 volts. In the shown design the current is restricted to 2 amps as displayed, although could be enhanced to 5 amps or even more by opting for a smaller sized current sensing resistor (0.3 ohm).

The 2N3055 and TIP122 transistors must be installed on appropriate heat sinks and the current sense resistor needs to be specified at 3 watts or maybe more.

Voltage regulation is actually managed through 1/2 of a 1558 or 1458 op-amp. The 1458 could be replaced in the circuit listed below, however it is advised the supply voltage to pin 8 always be restricted to 30 VDC, that may be attained with the addition of a 6.2 volt zener or 5.1 K resistor in series with pin 8.

The highest level DC supply voltage intended for the 1458 and 1558 is 36V and 44V correspondingly. The power transformer needs to be competent at the specified current yet sustaining an input voltage of a minimum of 4 volts greater than the specified output, however, not beyond the absolute maximum supply voltage of the op-amp using nominal load circumstances.

The power transformer displayed is actually a center tapped 25.2 volt AC / 2 amp device that may offer regulated outputs of 24 volts on 0.7 amps, 15 volts with 2 amps, or 6 volts at 3 amps.

The 0-24V, 5 amp variable power supply output will be acquired making use of the center tap of the transformer using the switch within the 18 volt situation. Just about all parts should really be gotten from any reputed online electronic store along with the opamp IC.