Electronic Circuits and Diagram-Electronics Projects and Design

Sound Level Meter Circuit Description This is a one chip sound level meter that can be use for displaying sound level of an amplifier or simply the sound level from a microphone.The heart of the circuit is  IC LM 3915 Audio level IC.Even though it is a stand alone IC , a peak detector based on Transistor BC 558  and diode 1N4001  is also included for better performance. Tips Supply voltage  can be  from 3V to 20V.The input is set for  audio line voltage (1V peak to peak) and has a max  input voltage of 1.3V.   To make the circuit…

Stereo Amplifier Circuit Description Here is the circuit diagram of a  powerful and high quality stereo amplifier using IC TDA 1554.The circuit has only very few components.The circuit works best with a 4 Ohm speaker. TDA1554 is a 4 x 11 watt integrated Class-B audio amplifier from Phillips.Since the IC can be operated from 12V it finds a lot of application in car audio systems.The TDA1554 has a lot of good features like thermal protection, reverse polarity protection, load dump protection, short circuit to ground protection, excellent ripple rejection, no switch ON/OFF thud etc. The IC can be wired in…

Digital Volume Control Circuit Description This is the circuit diagram of a digital volume controller for any sort of audio amplifiers or almost any circuit where a mechanical potentiometer is there(conditions apply). Simple and low cost, the heart of the circuit is DS 1669 digital potentiometer IC from Dallas Semiconductors.The circuit has no external components other than two pushbutton switches and a capacitor. Tips S 1 increases the volume & S2 decreases. The input audio signal must be not less than -0.2 Volts. If some clipping problem occurs, use a dual power supply of +5 & -5V.( Not shown in…