Archive for category: Power Supply circuits

Fuse Monitor Indicator

Power Supply circuits | By: Diagram mania

Circuit : Andy Collinson Email me Description: The idea for this project may have come to me in a flash of inspiration, and its a very simple way to check if a fuse has blown without removing it from its holder. Notes The simplicity of this circuit uses just two components, but with just one […]

Unregulated PSU

Power Supply circuits | By: Diagram mania

Circuit : Andy Collinson Email me Description: A basic full wave rectified power supply is shown below. The transformer is chosen according to the desired load. For example, if the load requires 12V at 1amp current, then a 12V, 1 amp rated transformer would do. However, when designing power supplies or most electronic circuits, you […]

Variable PSU

Power Supply circuits | By: Diagram mania

Circuit : Andy Collinson Email me Description: A variable power supply with adjustable voltage and current outputs made with the L200 regulator. Notes Using the versatile L200 voltage regulator, this power supply has independent voltage and current limits. The mains transformer has a 12volt, 2 amp rated secondary, the primary winding should equal the electricity […]

Variable Voltage Regulator

Power Supply circuits | By: Diagram mania

Circuit : Ron J Email me Notes As Ron suggests, controlling the output voltage from a regulator can be made variable in three ways:- 1. Using a fixed reference zener diode to increase the output by the value of the zener 2. A variable resistor for variable output, note that a voltage less than the […]

LM317 Voltage Regulator

Power Supply circuits | By: Diagram mania

Circuit :Matthew Hewson Email: matthew.hewson@ntlworld.com Description: I constructed this voltage regulator to power my two way mobile radio from the car cigarette lighter circuit. It has many other uses and the voltage can easily be adjusted by the use of a potentiometer. The voltage regulator is an LM317T, and should accept up to about 14 […]

Basic UPS

Power Supply circuits | By: Diagram mania

Circuit : Andy Collinson Email me Description This circuit is a simple form of the commercial UPS, the circuit provides a constant regulated 5 Volt output and an unregulated 12 Volt supply. In the event of electrical supply line failure the battery takes over, with no spikes on the regulated supply. Notes This circuit can […]

Alarm Power Supply

Power Supply circuits | By: Diagram mania

Circuit :Ron J Email Ron Description A 12 Volt power suppiled designed for Ron’s Modular Burglar Alarm. However, being a popular supply voltage this circuit will have many other uses as well. Notes This Power Supply is suitable for the Modular Burglar Alarm. However, it has other applications. It is designed to provide an output […]

The Output Adjustable Flyback Converter

Power Supply circuits | By: Diagram mania

Circuit : Simon Oh Email: Simon@SoftSwitching.com This circuit may also be downloaded in PDF format, please click here. Description A high voltage step-up DC power supply using adjustable flyback conversion. Specification Vin = 220Vac +-10% @ 50/60Hz Vout =0~600Vdc @ 0.25A Switching Frequency: 70~100KHz Design Guidelines DCM mode, output power is 200W The input RMS […]

9 Volt 2 Amp PSU

Power Supply circuits | By: Diagram mania

Circuit : Andy Collinson Email me Description A simple 9 Volt 2 amp supply using a single IC regulator. Notes There is little to be said about this circuit. All the work is done by the regulator. The 78S09 can deliver up to 2 amps continuous output whilst maintaining a low noise and very well […]

Current Limiting Power Supply

Power Supply circuits | By: Diagram mania

Circuit : Ron J Email Ron Description This is a 1-amp variable-voltage PSU. It adjusts from about 3v to 24v: and has the added feature that you can limit the maximum output current. This is invaluable when (for example) you power-up a project for the first time or soak-test a piece of equipment. Notes SW3 […]