Power Supply Circuits and Projects

 

Power Supply Circuits and Projects


12V 1A Power Supply Circuit

This 12V 1A power supply using zener diode and transistors allows us to obtain an output of approximately 11.4 volts with a very small percentage variation for a wide variety of loads.

15V Power Source ON delay circuit

15V power source ON delay using LM317. This circuit uses the LM317 voltage regulator. It also uses a transistor and an a electrolytic capacitor

9VDC Power Supply using Zener and Transistor

9VDC Power Supply using Zener diode and Transistor

This Power source can be used to power circuits or electronic devices that would normally use a 9 volt battery, saving us the cost of the battery while being used at home.

12V to -12V DC converter circuit using 555

12 VDC to -12 VDC converter circuit with a 555 IC.

This 12 VDC to -12 VDC converter circuit gives -12VDC (negative 12 volts) from a power source of + 12VDC (positive 12 volts), with very few components.

4 Amp Variable Power Supply with 3 LM317

4 Amp Variable Power Supply with 3 LM317

4 Amp Variable Power Supply with 3 LM317 voltage regulators and a LM308 precision operational amplifier. Output voltage from 1.25 to 30 volts.

1.5 v Joule Thief Circuit with no Toroid Coil

1.5 v Joule Thief Circuit with no Toroid Coil

This 1.5 V Joule Thief circuit can turn ON one LED. The circuit do not use a toroid coil but it is possible to turn on a common red, green or yellow LED

12V to 9V DC Converter Circuit Diagram (PCB)

12V to 9V DC Converter Circuit Diagram (PCB)

This 12V to 9V DC converter is very useful for powering 9V DC devices in a car that uses 12V battery. The maximum current consumption allowed by this circuit is 0.8 amps.

20 Amp Variable Power Supply using LM317

20 Amp Variable Power Supply using LM317

20 Amp Variable Power Supply with an output voltage from 1.5 to 15 volts using the LM317 regulator and 4 2N3055 power transistors to amplify the current capacity

12V to 24V Converter Circuit

12v to 24v converter

This 12VDC to 24VDC step up converter is very useful to power devices that run on 24 VDC when we have a 12VDC voltage source as it could be a car battery or alike.

12V Power Supply using Zener and 741 Op. Amp.

12V Power Supply using Zener and 741 Op. Amp.

This 12V Power Supply has, as its main characteristic, a low output impedance. This is a very desirable feature in voltage sources and is achieved with a large open loop gain that the operational amplifier has.

Surge Protection Circuit (Voltage Delay Circuit)

Surge Protection Circuit (Voltage Delay Circuit)

This Surge protection circuit is placed between the DC voltage source and the circuit that you want to power. This circuit delays the voltage given by the power source and allows the voltage to be applied to the circuit or device a few moments later.

12 volt Power Supply using 7805 regulator

12 volt Power Supply using 7805

This 12 volt power supply circuit is simple and very useful. Sometimes a 12 Volt power source is needed, and we only have 5 or 9 volt regulators (7805, 7809)

12 to 5 volt Converter Circuit (for cars)

12 to 5 volt converter circuit (for cars)

This 12 to 5 volt converter circuit for cars is very useful. It can be used to connect 5-volt electronic devices in a car with a 12v battery. (Automotive lead-acid batteries may have a voltage of up to 13.5 volts).