SparkFun Forums

[Paul81]

After looking at one of the example schematics for the LM386N audio preamp - on the output in there's a cap and resistor pulled down to ground then the electrolyic cap and speaker's 8 ohm helps filters out unwanted frequency noise. I was a bit confused on why there was a ceramic cap and a resistor being pulled down to ground - is that to smooth out the ac frequency signal?

[Valen]

This is what I found on this page:

https://lowvoltage.wordpress.com/2011/0 ... amplifier/

The 0.05uF capacitor and 10 ohm resistor pair from pin 5 to ground turns out to be called a “Boucherot cell” or “Zobel Network” and is used to prevent high frequency oscillations.

http://en.wikipedia.org/wiki/Boucherot_cell
http://en.wikipedia.org/wiki/Zobel_network