Low Dropout Single Rail Adjustable Power Supply Unit

In this project we design high current, high accuracy single rail variable power supply unit using Micrel’s MIC29152 voltage regulator IC. Thanks to the Micrel’s Super Beta PNP fabrication process this regulator has 80mV to 600mV dropout at the full load. With the given values of R1, R2 and TR1, this unit delivers 1.3V to 20V with maximum of 1.5A current.

This power supply unit is ideal for most of the analog electronic experiments, as a simple battery charger, as laboratory power supply, etc. Complete circuit diagram, PCB pattern and Eagle source files of this project are available to download in here.

When building the circuit make sure to install suitable heat-sink to the MIC29152 chip. This circuit use 230V AC power source, so make sure to apply all the safety precautions while at the designing and testing phases.

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