Diode Clipper and LM386 questions

[Yoa01]

Hi all,

I have two questions for you today. The first is about a diode clipper. I am pretty sure this design would clip a signal, but testing it in LTSpice with a sine wave running at 9v yields a constant 7.6v. Is something wrong here?


Secondly, I adapted the amplifier circuit from the LM386 datasheet and added a couple caps and a potentiometer for adjusting gain. I have seen in many 386 amp designs that those bypass or decoupling caps are used, yet the datasheet doesn't show them. Same with the caps leading into pin 3. Are they necessary?


Thank you!

 

[(*steve*)]

I have two questions for you today. The first is about a diode clipper. I am pretty sure this design would clip a signal, but testing it in LTSpice with a sine wave running at 9v yields a constant 7.6v. Is something wrong here?

Yes. It should clip.

Secondly, I adapted the amplifier circuit from the LM386 datasheet and added a couple caps and a potentiometer for adjusting gain. I have seen in many 386 amp designs that those bypass or decoupling caps are used, yet the datasheet doesn't show them. Same with the caps leading into pin 3. Are they necessary?

The best bet is to read the datasheet. They may be required under certain circumstances, or have to have certain values.

Or, they may not be required at all, and are performing a function external to the 386 amplifier.

 

[Yoa01]

I ran a real test, running a synth through it, and it did clip very well, though a bit quiet. Probably should have done that before posting, sorry...

Ok, I'll do that. Makes more sense anyway. Thanks!