Electronic Stethoscope

[UH3455]

Hi all,


            I have been working in the Electronic stethoscope 2. I would like to get the transfer function of this schematic, but I have not been able to get it. I get stuck at the non-inverting terminal of the LM386 power amp. Can any one tell how to solve from there?


Thanks,

UH3455

 

[audioguru2]

Hi UH,
The LM386 is a linear non-inverting power amplifier with built-in negative feedback for a voltage gain of 20. It also has built-in internal biasing so that its inputs work at ground which is its negative supply voltage. Its datasheet is here:

LM386.pdf

 

[UH3455]

Thanks for the data sheet.


            I was trying to get the transfer function so I can put it in my formal report for my class. I have an experimental bode plot that I measured, but the plot only tells me where the poles and zero are  located.


UH3455