When the input voltage (output of the rectifier section) increases, the output voltage of the regulator (Vout) also increases. Breakdown voltage of the zener diode D2 must be chosen according to the output voltage you need, and it is according to the equation, Vout = Vz – 0.7. Hi friends The capacitor shown are rated for 50volts hence the cannot be more than 35volts.
Hi KE730 in series regulators when you use it at very low voltage at max current, with high voltage input the series pass transistor will get heated up, hence you have to use a good heat sink. D2 should have been shown as 500mw zener of voltage rating equal to, output voltage required plus 1.4 volts. Hi Mark you are correct it is not included you can use a simple fast acting fuse in the output as indicated in the notes. Your use of this website constitutes acknowledgement and acceptance of our Terms & Conditions.
If you've been doing any circuitbuilding or electronic engineering technician work, you know how important a DC power supply is. Smoothing Capacitor- The next component after the full-wave rectifier is the smoothing capacitor. A regulator is a device that "regulates" voltage so that a perfectly smoothing DC voltage is output.
R1 Resistor and R2 Potentiometer- The next components needed are the R1 resistor and R2 potentiometer.
This is because when we use a regulator, we input a voltage into it and it outputs the voltage, based on the values of resistor R1 and potentiometer R2.
This creates a lot of heat, since the voltage difference between input and output voltage is so great.

This product is currently unavailable, but you may contact the supplier directly, for further interest. The circuit was designed to provide a variety of voltages to some electronic equipment with the use of a 12V battery as the power source. The circuit is intended to produce a power supply unit that that utilizes a single LM338 voltage regulator to provide an output voltage of 13.8 V while carrying a current of 5 A. The circuit has been designed to produce a power supply that will generate 30 Volts with 2 A current by utilizing the MC1466L integrated circuit with the aid of multiple Darlington transistors. The circuit is designed for power supply protection by limiting the amount of maximum output current to prevent any further damage to take place inside the power supply as well as the external circuit connected to it.
The circuit was designed to create a DC power supply that will be rated with 13.8 V and 20 A while having a current limiter and short circuit protection. M10-MPD303 - PROGRAMMABLE DC POWER SUPPLY, View POWER SUPPLY, MCP Product Details from Shanghai MCP Corp.
Such transistor voltage regulators are suitable for application where high output current is required. This increase in Vout decreases the base emitter voltage of Q2 because the zener diode D2 is operating in the breakdown region and the voltage across it is unchangeable. But having a 3-prong plug is better because ground provides better against possible electric fires. Therefore, we lower the very high voltage that we get from the mains outlet from the wall into a smaller voltage. A step-down transformer is a great device for lowering voltage from a mains AC voltage line.
First, it serves to further smooth out the fluctuating signal, so that it's a perfectly smoothing DC signal.

This potentiometer decides how much voltage is output, just like how you turn the knob of a professional-made DC power supply. If you require further details regarding the transaction data, please contact the supplier directly.
Resistor R1 provides the base current for Q1 and also keeps the zener diode D2 in the active region. This decrease in VBE increases the collector emitter resistance  of Q2 and so the output voltage (Vout) gets reduced accordingly. This reduces the collector emitter resistance of Q2 and so the output voltage gets increased accordingly. By connecting 2.2k 3watt wire wound potentiometer in parallel with the zener diode and connecting the slider of the potentiometer to base of Q1 base will make it a simple variable bench supply, which is still in service with me. However, if the potentiometer is set to near 0?, the regulator outputs approximately 1.25V.
This is the reason why professional DC power supplies always have large heat sinks in the back of them. Additional series pass transistors have to be added to the 7805 based regulator circuit for improving their current capacity. Illuminated rocker switch, 3-wire grounded 60 inch (152cm) power cord.We also carry more Power Supplies.