Category Archives: Power Supply

Power supply schematic diagram

5V DC Regulated Power Supply with Short Circuit Protection

This is the circuit diagram of 5V DC regulated power supply which featured with short circuit protection system. There are 2 kind of output that are regulated 5V DC with short circuit protection and without circuit protection. The main circuit is protected from any damage due to short-circuit in the additional power supply circuit by […]

Variable / Adjustable DC Power Supply 1.2V – 25V using LM338K

This is variable DC power supply circuit, or we can call it adjustable DC power supply which give us a 1.2V-25V output voltage. The power supply schematic above is taken from the datasheet of regulator LM338K manufactured National Semiconductor. The circuit uses IC LM338K as the voltage regulator, so we will get the stable and […]

1 – 9V Variable Desktop Power Supply

Here the variable desktop power supply which will convert a high input voltage (12V) from the SMPS / PSU of a desktop computer into small output voltage (1.25 to 9 volts). This converter will be very beneficial for electronics hobbyists. An adjustable three-pin voltage regulator chip LM317T (IC1) is applied right here to deliver the […]

4-Output Stage (5V/6V/9V/12V) Stabilized DC Power Supply

This is definitely an effective 4-output stage stabilized DC power supply unit for testing electronic circuits. It delivers very well regulated and stabilised output, that is important for most electronic circuits to provide good results. The circuit gives you an audio-visual indication if there is a short circuit in the PCB under test, so the […]

5V Regulated Power Supply with OverVoltage Protection

This is the circuit diagram of 5V Regulated Power Supply circuit, featured with over voltage protection. The circuit is based regulator chip 7805; Thyristor SCR 2N1595 and Dioda Zener 1N3997 for overvoltage protection circuit. The 5V regulated power supply is apply 74LS series integrated circuits which has to be really precise and tolerant of voltage […]

3-Rail (+12V) / (+5V) / (-5V) Regulated Power Supply

This circuit generates 3 source regulated voltages applying a minimum of electronic parts. The output DC voltage are +12V ; +5V and -5V. Diodes D2 and D3 conduct full-wave rectification, at the same time charging capacitor C2 on each halves of the alternating current cycle. At the same time, diode D1 with capacitor C1, and […]

3A Switching Power Supply Regulator

This is the circuit diagram of 3A switching power supply regulator: Simple and cheap, the circuit built based on well-known IC regulator LM317 with current booster of power transistor 2N3782. Don’t forget to add heatsink especially for power transistor 2N3782.