Microphone Amp

Posted on Feb 6, 2014

This is a simple circuit that can detect sounds by using a common condenser microphone. Sensitivity is variable. The circuit`s output becomes High each time a sound is detected, otherwise it is in low level. You can use it in simple robots for sound responding (e. g. reaction -> when you clap your hands). This circuit recognize human voice as a co

Microphone Amp
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mmon sound (you can`t use it for voice recognition). The microphone stage captures the sound and converts it to electrical signal. The amplification stage amplifies the signal and the comparator changes the output level if the amplified signal is higher from the reference voltage. Also you will need a stabilized 5 Volt external power supply. You can use a 4. 5 Volt battery or even a 9 Volt battery. Be aware that with the 9 Volt battery the output level will be also at 9 Volt (not TTL logic). Attention: Vdd is the power supply (5 or 9 Volts). You can also use a 4. 5 Volt battery. You adjust the sensitivity by turning the pot. The circuit can be extremely sensitive and can detect low sounds or even whispers.

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