Hi, in my first post- need help or advice for designing audio amplifier circuit.
I have to design an audio amplifier circuit. We are told the impedance of the headphones and the minimum voltage they require and also the voltage source. After researching I have found that the LM386N-4 is a popular choice. According to a datasheet of LM386N-4 - https://www.icrfq.com/part/2377557-LM386N_4.html I've seen many circuit diagrams but what I don't understand is how to pick the voltage gain needed for the amplifier.
I originally thought that need to know the input audio signal voltage and when I multiplied that by the gain that would need to give the minimum voltage required by the headphones, but it appears that what matters is the current which I don't get.
And are you able to design such a circuit without knowing about the audio input signal? If you do need to know about it what is it you need to know about it and why?
I would greatly appreciate any help as I am very lost.
Thanks in advance.