Free Circuit Diagram

Many new computers now only has USB port, and this serial to USB adapter might be the only help for old devices that provides only RS232/COM Port. This serial adapter uses FT232 USB-RS232  converter IC from FTDI (Future Technology Devices International).  The main features of this USB serial adapter chip are: 384 [...]

This low drop out (LDO) voltage regulator need only few components, with very low noise and very low drop-out voltage. The circuit illustrated in the schematic diagram below gives a fixed 2.77 volt output, but this output voltage can be adjusted using two additional resistors. This circuit capable to supply 300 mA load [...]

Using this circuit, you can measure the actual output power of your amplifier.  You can put this circuit in a box as a measurement instrument, or you can integrate it inside your power amplifier to get real power display. The circuit’s schematic diagram is shown in the figure below. This  circuit would be [...]

This is an audio amplifier circuit which has power of 18W. It is very simple but it has a high quality. This circuit does not require pre amplifier. It can be directly connected to tuners, tape recorders, and CD players. It produces 18 Watt RMS into 8 Ohm (1KHz sine wave) output.this circuit has a [...]

This testing instrument provide two alternate fuction: signal injector and signal tracer.  This audio signal tracer/injector is very helpful in trouble shooting audio circuits, when you need to test a circuit by injecting a signal and observe the output (by watching the oscilloscope or by hearing the loudspeaker for example), or by tracing some points [...]

This is an audio line driver circuit using a TSH22. The advantages of this circuit are low distortion, exhibits a wide bandwidth and an output current sufficient to drive medium impedance loads at a high level modulation. Here is the circuit : This circuit uses two TSH22 that is used in [...]