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 DC battery. The maximum current consumption allowed by this circuit is 0.8 amps.

Transformerless Power Supply Circuit We will use a zener diode among other elements to acheive the Transformerless Power Supply circuit. This  means that our power supply will give a limited range current value (it will be a maximum and a minimum posible current that the power supply circuit can deliver). This power suply must be permanently connected to the circuit as a whole unit. […]

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.

There are times when the amount of current that is required of a power supply exceeds its potential.

If the current demand is very high, the pass transistor of the voltage regulator may be damaged. On these cases it is necessary that the circuit has an overcurrent protection.

Transistor – Zener diode Voltage regulator circuit

This circuit delivers an output voltage established by the voltage of the zener diode less 0.7 volts. The 0.7 volts is the average voltage drop between the base and the emitter of a transistor. (Vbe)

Transistorized Voltage Regulator Using a half and a full-wave rectifier we can convert an AC voltage in a DC one. This converted voltage is unregulated, because the output DC voltage does not remain constant. The output voltage of a power supply may vary due to changes in the load value. To reduce these variations we connect a […]

Voltage regulator classification a) Linear voltage regulators Linear voltage regulators control the output voltage, continuously adjusting the voltage drop in a power transistor that is connected in series between the unregulated input and the load. Since an electric current must flow through the transistor all the time, the transistor have to operate in its linear region. Although they are simpler […]