12V / 3A Regulated Power Supply

12V / 3A Regulated Power Supply
Here we provide a powerful 12V / 3A regulated power supply circuit. Of course the circuit provides a 12V regulated power supply with output current up to 3 amperes. It is specially designed for use with 2m handheld rigs with linear power amplifier and CB portable QRP rigs. The power supply circuit uses monolithic IC CA3085 voltage regulator in 8-lead TO-5 package. Its salient features include good load and line regulation, output current up to 100mA (which can be

12V DC Power Supply without Transformer

12V DC Power Supply without Transformer
These are 12V DC power supply circuit which designed without transformer (trafo). These circuit use capacitive reactance instead of resistance; and it doesn't generate very much heat.The circuit draws about 30ma AC. Always use a fuse and/or a fusible resistor to be on the safe side. The values given are only a guide. There should be more than enough power available for timers, light operated switches, temperature controllers etc, provided that you use an optical isolator as your circuit's

12V / 20A Regulated DC Power Supply

12V / 20A Regulated DC Power Supply
Here the circuit diagram of 12V / 20A Regulated DC Power Supply using 5 pieces of power transistor MJ2955, voltage regulator 78S12. It will give you regulated output voltage of 12V-15V 20A. A 350VA transformer power, the primary winding 230 , secondary winding is 18V . The secondary voltage of 18V with the load of the transformer , the voltage at idle , it is customary in the case of such efforts is higher than 5 % to 10

Simple Variable Power Supply 1.5 – 30V, 5A

Simple Variable Power Supply 1.5 – 30V, 5A
The power supply is based on two chips and in addition they contain only a few discrete components. In this regard, it is easy to manufacture and configuration. At the same time, the power supply provides a high level indicators, such as the smooth adjustment of the voltage in the large range, low coefficient of fluctuation, the output current up to 5A with the ability to stabilize the current, high reliability. Also, the power supply has short circuit protection.

Transformerless power supply FET

Transformerless power supply FET
The circuit shows a diagram of a simple transformerless power supply for transistor BUZ41A. Through the inclusion of the common-drain transistor VT1 NW capacitor charging to a voltage of about 3 smaller than the zener voltage of VD4. An alternating voltage with a phase shift, determined by the capacity of the capacitor C1, transistor opens VT2, which stops the charge capacitor NW at the beginning of each positive half-wave supply voltage. (more…)

1.5-25V Power supply with preregulator

1.5-25V Power supply with preregulator
This circuit using KR142EN12 (analog - LM317 ) ic regulator that can handle load currents up to 2 amperes. For higher currents can be used IC LT1083/84/85 that each can handle currents 7/5/3A. 2000uF capacitor C3 is selected from the calculation of the current 1 Ampere. Resistor R9 is used as a current sensor to an ammeter. (more…)