Power pack for battery-powered devices

This circuit provides a regulated output voltage ranging from 5 V to 15 V DC, which can be adjusted using a preset resistor. The current output can reach up to approximately 350 mA. An integrated circuit is utilized to regulate the output voltage; although the IC (7805) is typically employed for a fixed voltage supply of 5 V DC, it is configured here for variable output voltage.

The circuit utilizes the 7805 voltage regulator integrated circuit, which is primarily designed to deliver a stable output voltage of 5 V. However, in this application, it is adapted for variable voltage regulation. The key components include the 7805 IC, a preset resistor (potentiometer), input and output capacitors, and a heat sink if necessary, depending on the power dissipation.

The input voltage to the circuit should be higher than the maximum output voltage, typically by at least 2-3 V to ensure proper regulation. The preset resistor allows for fine-tuning of the output voltage within the specified range of 5 V to 15 V. The output current capability of up to 350 mA makes this circuit suitable for various low-power applications.

To ensure stability and reduce noise, decoupling capacitors are placed at the input and output terminals of the 7805 IC. A common configuration includes a 0.33 µF capacitor at the input and a 0.1 µF capacitor at the output. These capacitors help filter any high-frequency noise and provide a stable voltage output.

When designing the circuit, it is essential to consider the thermal performance of the 7805, especially at higher output currents. A heat sink may be required to dissipate heat generated during operation, thus preventing thermal shutdown of the regulator.

In summary, this circuit effectively converts a higher DC voltage to a regulated output voltage adjustable between 5 V and 15 V, making it versatile for various electronic applications while ensuring stable operation and adequate current supply.This circuit gives a regulated output of between 5 V and 15 Vdc, adjusted and set by a preset resistor. Current output up to about 350 mA An integrated circuit regulates the output voltage and although this IC (the 7805) is normally used in a fixed-voltage (5 Vdc) supply it is for a variable output voltage.