Heat Sink - Basics

As power transistor handle large currents, they always heat up during operation. Since transistor is a temperature dependent device, the heat generated must be dissipated to the surrounding in order to keep the temperature within permissible limits. Generally, the transistor is fixed on a metal sheet (usually aluminum) so that additional heat is transferred to the Aluminum sheet. The metal sheet that serves to dissipate the additional heat from the power transistor is known as heat sink.

heat sinks
Fig-1:  Heat Sink (Aluminum Sheet)

Automatic Power Off Circuit Diagram

It is an automatic power off circuit diagram.  If you need to shut-off any electronic device after a set amount of time then this circuit can do that automatically; when you are even sleeping!  For example this auto power off circuit can be used with garden/porch light, soldering iron/ glue gun or similar other devices to auto shut it off for saving electricity or save the device, or you can use it to suit your own needs.

Auto Power Off Circuit
Auto Power Off Circuit Diagram

10W Audio Amplifier Circuit by TDA2030

The amplifier circuit by ic TDA2030 described here is an powerful audio amplifier with output power of 10W. TDA2030 is a monolithic IC, used as a low frequency class AB Amplifier. It has high output current and very low distortion. This 10W audio amplifier using TDA2030 is good for home/ small room.

Circuit Diagram of '10W amplifier circuit using IC TDA2030' with power supply.

tda2030 amplifier circuit
Fig-1: Circuit Diagram of 10W audio amplifier

12v Regulated Power Supply Circuit Diagram

Here this circuit diagram is for +12V regulated (fixed voltage) DC power supply. This power supply circuit diagram is ideal for an average current requirement of  1Amp. This  circuit is based on IC LM7812. It is a 3-terminal (+ve) voltage regulator IC. It has short circuit  protection , thermal overload protection.  LM7812 IC is from LM78XX series. The LM78XX series IC is  positive voltage regulator IC for different voltage requirements, for example LM7805 IC is made for 5 volt fixed output voltage . There is LM79XX IC series for negative voltage .

Circuit diagram of 12v regulated power supply

12 volt power supply circuit
Fig: 12V power supply circuit diagram

Simple FM Transmitter Circuit Schematic

This is a simplest FM transmitter circuit schematic with a single transistor. It build with a very few numbers of components include a transistor, few capacitors, resistors and a small microphone.

Clap Switch Circuit Diagram Project

This is a simple clap switch circuit diagram project. If you are a beginner electronics learner, and love to do new project experiment then this is a great circuit for you.  This circuit can on/off a 220V electronic device like fan, lamp by the sound of clap.

Circuit diagram of clap switch