When to Choose ESR vs. Ripple

[bgavin]

When choosing a motherboard cap, which is most crucial to the choice, ESR or RIPPLE?

Given: KG7 board populated with TEAPO 10x25 3300uF SM series craps.
ESR=16
Ripple=3290

The Samxon GD has a lower ESR=12, but also a lower Ripple=2800.

My inclination is to choose the lower ESR cap, but my question is about choosing a cap with a reduced ripple spec.

Thoughts?

[PCBONEZ]

Re: When to Choose ESR vs. Ripple

The problem is you have the Teapo data wrong:


The GD is superior for both ESR and Ripple.

[Big Pope]

Re: When to Choose ESR vs. Ripple

Given: KG7 board populated with TEAPO 10x25 3300uF SM series craps.
ESR=16
Ripple=3290

Where you get this Teapo SM datasheet?

[kc8adu]

Re: When to Choose ESR vs. Ripple

doesnt look right.
lower esr=higher ripple handling capability.

[PCBONEZ]

Re: When to Choose ESR vs. Ripple

See link in my above post for correct Teapo SM specs.

bgavin,
I think you have a bum Teapo data sheet or maybe a data sheet for some SM series that is not Teapo.

[Big Pope]

Re: When to Choose ESR vs. Ripple

See link in my above post for correct Teapo SM specs.

bgavin,
I think you have a bum Teapo data sheet or maybe a data sheet for some SM series that is not Teapo.

Agree, there is many brands have SM series.

[zandrax]

Re: When to Choose ESR vs. Ripple

The datasheet seems the rigth one, but bgavin read the 3900 uF specs - for 3300 uF caps Esr is 18 mOhm and Ripple is 2770. So the Samxon is better for both Esr and [slightly] Ripple.

Zandrax

[davmax]

Re: When to Choose ESR vs. Ripple

It is best to focus on the Samxon GC as a replacement, far better and more readily availablethan the GD.

ESR= 9 mohm Ripple 3190mA

[PCBONEZ]

Re: When to Choose ESR vs. Ripple

zandrax
That doesn't follow completely either. - The 3900 is 13x30 mm

This is the second I've seen a wrong number for Teapo SM pulled up recently.
I think both times were bgavin. (May have been the same cap too... don't remember.)
I think he mentioned he made a database for cap specs and possibly he entered something wrong. Easy to do after looking at data sheets too long.

I'm only pointing it out so he can fix whatever the glitch is and avoid future confusion when he's looking things up.

.

[bgavin]

Re: When to Choose ESR vs. Ripple

This is the second I've seen a wrong number for Teapo SM pulled up recently.
I think both times were bgavin. (May have been the same cap too... don't remember.)
I think he mentioned he made a database for cap specs and possibly he entered something wrong. Easy to do after looking at data sheets too long.

I'm only pointing it out so he can fix whatever the glitch is and avoid future confusion when he's looking things up.

Without a tone of voice on the internet, it is difficult to tell if I'm getting spanked or corrected. I ask you this question because your tone is borderline spanking.

I enter thousands of data points in my data library, so it is very easy to have a typo. It is also very easy for you to sit in the armchair and criticize any error I make. I don't pointedly rub your nose in your erroneous posts, so don't do it to me.

I am annoyed with the non-contributory bandwidth wasted on making sure I "avoid future confusion." It would be a lot easier to just answer the question. I don't need anybody pontificating at my expense.

So, are we spanking or contributing?

The TEAPO data sheet PDF is 4/28/2004, SM series.
My database is correct, my error was looking at 3900uF for a different board, and crossing my input to the post.

I would still like to know if ESR or RIPPLE is the determining factor for choosing between two caps with similar specs.

[zandrax]

Re: When to Choose ESR vs. Ripple

Without a tone of voice on the internet, it is difficult to tell if I'm getting spanked or corrected. I ask you this question because your tone is borderline spanking.

I enter thousands of data points in my data library, so it is very easy to have a typo. It is also very easy for you to sit in the armchair and criticize any error I make. I don't pointedly rub your nose in your erroneous posts, so don't do it to me.

I am annoyed with the non-contributory bandwidth wasted on making sure I "avoid future confusion." It would be a lot easier to just answer the question. I don't need anybody pontificating at my expense.

So, are we spanking or contributing?

Don't get mad: nobody want to spank or judge you for a mistake because everone makes mistakes.
I read PCBONEX' post as an indent, a hint: correct quickly your datasheet before forgetting about it, so you can avoid the same mistake in future.
If your datasheet is correct and you simply read the wrong specs, be more carefull next time.

The TEAPO data sheet PDF is 4/28/2004, SM series.
My database is correct, my error was looking at 3900uF for a different board, and crossing my input to the post.

I would still like to know if ESR or RIPPLE is the determining factor for choosing between two caps with similar specs.

According to kc8adu it's the same: lower esr means usually higher ripple handling, so a better cap under both points of view.
If you are forced to choose between two caps which specs are almost identical, my common sense suggests to choose the lower esr one.

Zandrax

[gdement]

Re: When to Choose ESR vs. Ripple

Doesn't a lower ripple rating imply that the cap is more likely to fail under stress? Seems that if the ESR is adequate, then higher ripple would make a safer substitute, especially given that the original presumably was under some stress.

[PCBONEZ]

Re: When to Choose ESR vs. Ripple

bgavin
-
Just trying to assist really.
I tried before and you missed it.
Some other posters were confusing what I was trying to get across.
I got loud so you wouldn't miss it again.
Maybe too loud. Sorry. (I do that..)

Just wanted you to know there was a mistake so you can fix your DB if that's what the problem was.

---

You want ripple equal to or higher.
You want ESR equal to or lower.

They tend to go hand in hand.
As ripple rating gets higher the ESR gets lower.
-
I think if you had a case where one was 'out' and the other was 'in' the caps would be so close overall that it wouldn't matter.

ESR relates to how effective/easily the cap can filter ripple out of the circuit.
Ripple relates to how much heat builds up in the cap while doing it.
[Lower resistance (ESR) -> less heat internally -> can handle more ripple... U C?]

If I can't get them both close to or better than the original I'll choose another series of cap. - I will not go less than the original for either unless it's a TINY bit.
-
The reason is to be SURE it's actually safe to go below I'd have to do a circuit analysis and a bunch of math and 1) I don't have time and 2) I'm too lazy.
It's easier to just find a better replacement.

.

[Big Pope]

Re: When to Choose ESR vs. Ripple

Now everything is clear, everybody take it easy.

[bgavin]

Re: When to Choose ESR vs. Ripple

The TEAPO data sheet PDF is 4/28/2004, SM series.
My database is correct, my error was looking at 3900uF for a different board, and crossing my input to the post.

I don't know how to make it any more clear: the database is not the problem.

It was a human problem of looking at one line, and thinking of another.

[PCBONEZ]

Re: When to Choose ESR vs. Ripple

Well yeah,,,
I know that NOW....
I didn't when I wrote the remark that started all this.
-
I'm sorry for trying to help.
Can we drop this part now?
.