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Brownish Tint on 0805 components

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#62249

Brownish Tint on 0805 components | 14 July, 2010

This has come up in the past, but I am ready to find an answer. A collegue immediately chalked it up to overheating the components. A check of that found otherwise. Not to mention it isn't all of them. For instance all the 104's 514's and 224's have the tint, however all the 102's 103's and 471's dont. So it isn't every component.

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#62257

Brownish Tint on 0805 components | 14 July, 2010

So, tell us more ... * Is this at in-bound inspection? Where do you observe this? * Does this affect the whole component, just terminations, ... * Could the 'brownish' be interpreted to be 'purplish'? * How wide-spread is this [eg, multiple products, lots, etc]?

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#62266

Brownish Tint on 0805 components | 16 July, 2010

After reflow, is where this is noticed.

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#62276

Brownish Tint on 0805 components | 19 July, 2010

Agreed, on some components we have seen a "brownish tint" after reflow it doesn’t happen on all of our resistors it only appears to be on the leads, and have also seen the purpleish tint on some other 2512 components

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#62278

Brownish Tint on 0805 components | 20 July, 2010

Normal.

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#62279

Brownish Tint on 0805 components | 20 July, 2010

Overheating

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#62280

Brownish Tint on 0805 components | 20 July, 2010

Negative.

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#62281

Brownish Tint on 0805 components | 20 July, 2010

> So, tell us more ... * Is this at in-bound > inspection? Where do you observe this? * Does > this affect the whole component, just > terminations, ... * Could the 'brownish' be > interpreted to be 'purplish'? * How wide-spread > is this [eg, multiple products, lots, etc]?

I will check in bound components.

The issues are only on the leads. I have seen several instances where the same component turns brown located directly next to another that does not.

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#62291

Brownish Tint on 0805 components | 21 July, 2010

Could be metalization or leaching as well.

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#62293

Brownish Tint on 0805 components | 21 July, 2010

Bingo!!!

Craig: You say, "I have seen several instances where the same component turns brown located directly next to another that does not."

What's the difference between the two?

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#62356

Brownish Tint on 0805 components | 2 August, 2010

My problem is that a 10k 0805 chip looks fine next to a 100k 0805 that is brown.

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#62360

Brownish Tint on 0805 components | 2 August, 2010

Right. Put thermal couples on both of them and determine what the blank is different.

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