Hi. Looking to make a toy megaphone, powered by 3V. It will be wimpy performing but wondering if there is a single chip solution to build such?
1 Watt is OK. Do you know ?
Not really, a megaphone requires a preamp and a power amplifier, easy to do with a couple of chips - however, there are numerous LM386 circuits put there, which 'may' work for a toy, such as this one:
This LM386 audio amplifier circuit can be used as “Small mic and loudspeaker system” for a small space like a room. This circuit can also be used in many applications like portable music players, intercoms, radio amplifiers, TV sound systems, Ultrasonic drivers etc.
circuitdigest.com
Main issues are mechanical rather than electrical.
Thank you. The LM386 may not work at 3V; but wishing for a modern equivalent for lower voltage operation... How far from reality is this, to connect a microphone directly and obtain reasonable loudness ? It claims a gain of almost 400... not enough ?
Only thing to do is try it and see - you don't need as much gain as you might think, as you're basically so close to the microphone. If you need a bit more you could always add a single transistor preamp.