Half rule broken

[Fir3Chi3f]

Re: Half rule broken

Although it's a little late, I found a thread on the exact monitor I've been working on. https://www.badcaps.net/forum/showth...?t=7900&page=2 In it mouser and Toasty both recommend replacement caps... I don't think I order one in common with the two.

Moving on, here is what I've ordered for each replacement:

Originals:
All CapXon GL

47uF 50v 11x6.3mm Ripple: 240-250 ESR: 0.44-0.65
680uF 25v 16x10mm Ripple: 920 ESR: 0.074
330uF 25v 13x10mm Ripple: ~722 ESR: ~0.095 (My own guessdimasion)
820uF 25v 10x20mm Ripple: 1280 ESR: ~0.052 (If I understood PCBONEZ correctly)

Replacements:

Rubycon 33uF 35V 5mm ZL Series Ripple: 250 ESR: 0.30
Samxon 470uF 25v 10mm GT Series Ripple: 1050 ESR: 0.069
Rubycon 220uF 25v 8mm ZLG Series Ripple: 1000 ESR: 0.036
Rubycon 680uF 16v 8mm ZL Series Ripple: 1250 ESR: 0.041

Value ranges are based off of data sheet estimates as the specific value wasn't listed. I don't think I'm going to replace those darn taicons just yet as I couldn't find any data sheets on them (although I'm sure someone here can prove me otherwise).

[PCBONEZ]

Re: Half rule broken

Research the Samxon GT.
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There are a couple of older Samxon series that are problematic.
I don't recall what they are for sure but GT sounds familiar.
[Or someone that remembers can pipe-up.]

[momaka]

Re: Half rule broken

I don't think I'm going to replace those darn taicons just yet as I couldn't find any data sheets on them (although I'm sure someone here can prove me otherwise).

What particular series are you looking for?
If I remember correctly, most of the Taicon series should correspond directly to Nichicon series since Taicon claims to be a subdivision of the Nichicon family. Not sure how much of that is true, but their series names do match indeed. For example, both Taicon and Nichicon have HD, PM, PW, and HE series. I do remember a discussion somewhere on this forum about Taicon and Nichicon and now their series were equivalent. Of course, Taicon is made in Taiwan and China so the quality is obviously not the same.

But in any case, if you just use Rubycon ZL for those, everything should be fine. At least from my experience, it seems that most LCD monitor PSUs don't seem to care that much what caps you put in them, as long as their ESR is the same or better than the original ones. That's why your poly caps didn't cause a problem. In computer PSUs, however, the ESR must be the same or at least very close.

There are a couple of older Samxon series that are problematic.
I don't recall what they are for sure but GT sounds familiar.

Samxon GF have been problematic. I remember seeing them in quite a few threads here in the past. I don't recall anything about GT, though.
Searching for Samxon GF shows quite a few threads where they were bad.
Searching for Samxon GT doesn't.
Plus, I doubt Topcat would be selling bad caps. Otherwise I'm sure one of his customers would have complained by now.

[PCBONEZ]

Re: Half rule broken

Yes, Taicon is in cahoots with Nichicon.
So if you see a Taicon series name and there is a Nichicon with the same series name you can look at the Nichicon data sheet.
- I do not mean to imply that their quality is the same. It isn't.
Their specs & design are the same but Taicon uses cheap Chinese materials and Nichicon uses Japaneses materials.

I also remember a Saxon GL that had issues.
Think those are obsolete so no data.
I didn't know TC sold Samxon GT.
Only Samxon I buy often are the RS series for PSUs.
.

[Fir3Chi3f]

Re: Half rule broken

I finally posted the tutorial, I'm still adding more - Including some direct quotes and shout-outs to a few of you here that have helped me out. Word of warning though, I've embedded most of the pictures into the thread and I know that annoys some.

http://www.overclock.net/monitors-di...l#post14362120

Let me know what you think!

[PCBONEZ]

Re: Half rule broken

Interesting style you have there.

You might wanna add RS Components as a source of parts for those folks across the big pond.
.

[Fir3Chi3f]

Re: Half rule broken

Interesting style you have there.

You might wanna add RS Components as a source of parts for those folks across the big pond.
.

Thanks PCBONEZ, gotta keep things interesting

Thanks for the suggestion, source has been added.

[momaka]

Re: Half rule broken

Awesome pictures, Fir3Chi3f. It made the tutorial quite enjoyable to read .

In your tutorial, though, I wouldn't say that the caps should be chosen mostly based on ESR and ripple current. It's better to keep the capacitance and voltage rating the same as the original caps. In fact, it's not recommended to go down in voltage (unless you've checked the circuit voltage already and you know the new lower-voltage caps are rated higher than that circuit voltage). Capacitance you can vary, but try to stay to within one level of the original caps, which is %20 (going %20 higher is usually better than going %20 lower). With all that said, ESR and ripple rating are still very important, but don't go *just* by those. Also, for the replacement caps, you can go with whatever can size you want (as long as ESR and ripple current match the original caps) - just make sure you can fit them on the circuit board and that the monitor lid can close properly afterwards.

[PCBONEZ]

Re: Half rule broken

In SMPS Filters:
In so far as filtering out Ripple Frequencies the ESR and Ripple are more important.
In so far as Transient Response (keeping the DC voltage steady with load changes) the uF is more important.
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As the frequency needing filtered goes up [as in filters for EMI instead of SMPS Ripple] at some point the uF becomes more important but there is an area in between [roughly over 100 kHz to about 1Mhz] where ESR and uF share the 'responsibility' [as it were].
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This is because at 100kHz the Z = ESR but, as Frequencies go up, the ESR goes up and the Xc goes down. The one with the most affect on Z is the one that is lowest at the Frequency being filtered.
.
.
If you don't know exactly what the circuit is up to then it's best to stick to the original values.
.