How can I simulate "Click and Pop noise" in Hspice

[wkjo82]

Hi.

My project is Class-D audio amplifier.(My circuit has BTL type, filterless. )

I have some trouble with Click & Pop.

I can't find Click & Pop in my circuit.

First of all, to see "Click & Pop", I control VDD in my whole circuit.

I mean, modulator, comparator, power stage and other circuit in my system have 0 volt at 0ms.

and then, after 0.5ms, it has VDD.

I try to see Click & Pop noise in this situation.

Is right method?

I can't certain, please tell me some information.




sorry, my eng skill is so poor

Thanks.

 

[mengcy]

Before your simulation, you have to know how the Click and Pop noise generates.

 

[wkjo82]

Re: How can I simulate "Click and Pop noise" in Hs

mengcy, thanks for your reply.

surely I know how the noise generates.

for example, power up, and down, mute-up and mute-down.

But, even though there is no suppression circuit in my system, Click & Pop is too small(around 100uV)

So, I have a doubt whether measurement method is right or wrong.

please give me some information

 

[monya11]

Re: How can I simulate "Click and Pop noise" in Hs

You need to have offset in your amp so that you can see larger pop/click. Do you simulate with an offset?

 

[wkjo82]

Re: How can I simulate "Click and Pop noise" in Hs

monya11, thanks for your reply.

I try to simulate with offset in opamp.

But, I don't kwow where be placed the offset.

I mean, place offset in front of system? or in power stage?

or place offset in output of opamp? or input?

And how offset place be in hspice?

To simulate pop noise, the input pair has ac ground.

I don't know make offset in DC voltage source.

please give me some information.

thanks

 

[monya11]

Re: How can I simulate "Click and Pop noise" in Hs

wkjo82

- It is difficult to say without seeing your architecture where would be best place to add offset.
- But as a general rule you need to add it at the input of your first amp a series voltage source with one of the inputs and you should be able to see pop at the output of your amp.