Need help with identifying this component 9jl

[AdrianM55]

Hello
Can anyone help me identifying this component please?

[bluebunny]

What's the board from?

[AdrianM55]

Boss RC -5

[Kevin Mitchell]

Can't find the service manual/schematic.
Seeing how they're near Q1, I'd assume they're rectifier diodes as Q1 is often the transistor used for dropping voltage in these boss pedals.
This is only speculation, but is likely the case IMO.

What they are specifically is beyond me. You can reverse engineer it a bit to see if they are used to rectify the AC input.

[Rob Strand]

The PCB designators are marked Cxxx so they are likely to be caps.   They look polarized so probably tantalums.

I haven't tried to decipher the marking code into a value + voltage, if that's even possible.  The marking style doesn't ring any bells regarding the brand.

Not the right parts but you can see a marking scheme.  Your caps use a different and more obscure scheme.
https://www.farnell.com/datasheets/1750764.pdf

[AdrianM55]

I am absolutely puzzled as I was convinced that I'm looking at rectifying/zener diodes but it can be a cap. Btw it's  shorted and appear to be heating up. I'll desolder it and see if short is away.

[Rob Strand]

I am absolutely puzzled as I was convinced that I'm looking at rectifying/zener diodes but it can be a cap. Btw it's  shorted and appear to be heating up. I'll desolder it and see if short is away.

If you are convinced those parts are heating up then it is possible they have shorts.  More often than not tantalum caps fail short - it's quite common, especially when they are put across power supplies which can dump large amounts of current through them.  (smaller packages don't help either)

[Rob Strand]

Btw it's  shorted and appear to be heating up. I'll desolder it and see if short is away.

Don't power it up though.  You could fry a lot of stuff with the cap pulled.


Another weird thing is there's more caps than designators!  What goes with what?

[Kevin Mitchell]

I am absolutely puzzled as I was convinced that I'm looking at rectifying/zener diodes

Personally, I've yet to see a chip capacitor encased in plastic.
Who's to say those capacitor designations belong to those locations? We only have a small preview of the board to go from after all.

[Rob Strand]

I am absolutely puzzled as I was convinced that I'm looking at rectifying/zener diodes

Personally, I've yet to see a chip capacitor encased in plastic.
Who's to say those capacitor designations belong to those locations? We only have a small preview of the board to go from after all.

It's not a chip cap it's a tantalum.  They have many package styles.

https://www.made-in-china.com/showroom/hbjessie/product-detaildqanUuZynXcE/China-Tantalum-Capacitor-TEESVA0J476M8R-.html

[Kevin Mitchell]

It's not a chip cap it's a tantalum.  They have many package styles.

https://www.made-in-china.com/showroom/hbjessie/product-detaildqanUuZynXcE/China-Tantalum-Capacitor-TEESVA0J476M8R-.html

Well played, Rob. You win this one 

[Rob Strand]

Well played, Rob. You win this one 

Only putting forward what is most likely.   The SMD stuff can be confusing, it bugs me too.   I wouldn't be overly shocked if they did turn out to be diodes.

[Rob Strand]

Looking at the pics the marking code is probably:  gJ1

I found this, see PDF p9 (doc p10), but it's a case of close but no cigar, as it is 3 digit,
https://www.tokin.com/english/product/pdf_dl/neocapacitor_e.pdf

gJ7 = 22uF 4V, gJ8 = 220uF.
A different manufacturer could assign a completely different meaning.

Like this one, Samsung, p16, if we drop the 1, we have one of gj Gj and GJ,  but the capital letter makes a difference!
http://www.kaien-hk.com/upfile/20100707101220771.pdf

gj = 0.22uF 4V, Gj = 2u2 4V,  GJ = 22uF 4V

but for Vishay, Page 2, gJ,  22uF 4V,
https://www.vishay.com/docs/40176/tmcj.pdf

Where I really suspect the g should be G!

Got no hope without working out the manufacturer from the style of the marking.

After some pondering:

First digit is likely to be voltage:  g, G = 4V
Second digit relates to the capacitance value:  j, J = 0.22u, 2.2u, 22u
However exactly what value depends on the case of the first and second digits,
and possibly a third digit!

Best guess so far gJ = 2.2uF 4V,   but is the last digit (1, L, l) significant?

[duck_arse]

from my point of squint, those four cap spots are in parallel. two empty spots for two caps, and one designator for the two-fitted-to-make-one cap. is that sensible?

[AdrianM55]

Looking at the pics the marking code is probably:  gJ1

I found this, see PDF p9 (doc p10), but it's a case of close but no cigar, as it is 3 digit,
https://www.tokin.com/english/product/pdf_dl/neocapacitor_e.pdf

gJ7 = 22uF 4V, gJ8 = 220uF.
A different manufacturer could assign a completely different meaning.

Like this one, Samsung, p16, if we drop the 1, we have one of gj Gj and GJ,  but the capital letter makes a difference!
http://www.kaien-hk.com/upfile/20100707101220771.pdf

gj = 0.22uF 4V, Gj = 2u2 4V,  GJ = 22uF 4V

but for Vishay, Page 2, gJ,  22uF 4V,
https://www.vishay.com/docs/40176/tmcj.pdf

Where I really suspect the g should be G!

Got no hope without working out the manufacturer from the style of the marking.

After some pondering:

First digit is likely to be voltage:  g, G = 4V
Second digit relates to the capacitance value:  j, J = 0.22u, 2.2u, 22u
However exactly what value depends on the case of the first and second digits,
and possibly a third digit!

Best guess so far gJ = 2.2uF 4V,   but is the last digit (1, L, l) significant?

So I was grabbing every moment today at work to find out and If I recall correctly I found something saying that it might be J type tantalum but can't find g(G) or l (L) meaning.

I haven't seen this kind of marking yet.

from my point of squint, those four cap spots are in parallel. two empty spots for two caps, and one designator for the two-fitted-to-make-one cap. is that sensible?

I think that's why I must unsolder the one that goes hot. And fingers crossed next one down is alive and ready to be "decoded".

Need to repair my ESR meter first tho.

Will report "bach" once I'll know more.

Thanks so far.

[Rob Strand]

So I was grabbing every moment today at work to find out and If I recall correctly I found something saying that it might be J type tantalum but can't find g(G) or l (L) meaning.

I went through quite a few more datasheets and there's a number of schemes in use.   Some aspects aren't consistent between the encodings but there's also common patterns.   I worked out a good deal of the patterns.    The first letter g (G) pretty much always means 4V.  The j (J) for the value is 2.2, 22 etc.

In your case the third alpha-digit is the confusing part. 

In the 3-digits schemes, like the tokin reference, 
- the first alpha-digit is the voltage, consistent with the 2-digit schemes.
- the second alpha-digit is the value digits, eg.  j, J = 2.2
- the last digit is multiplier when the value is in pF
eg.  J6 = 2.2 x 10^6 pF = 2.2uF, J7 = 2.2 x 10^7 = 22uF

Clearly a last digit of 1 doesn't make much sense for tantalums, J1 would be 2.2*10 pF = 22pF - an unrealistic value.  So in your case the 1 cannot be a multiplier.

There is another scheme with only upper case letters where a *leading* 1 and 0 is used as a multiplier for the voltage, 0E = 2.5V, 1E = 25V.   ; E = 2.5V, so 0E = 2.5V*10^0 = 2.5V and 1E = 2.5V*10^1 = 25V.  Again the
"1" in your case doesn't fit this pattern.

So the 1 in your case doesn't fit either of those cases.    It possible it has another meaning like type of tantalum or is related to the manufacturing date or factory.

Following the patterns and ignoring the third digit gives a fairly consistent estimate of 2.2uF and 4V.   Another supporting piece of the evidence is the size of the cap.   The cap size would be OK for 2.2uF 4V but it might be pushing it for say 22uF 4V, and definitely won't be 220uF 4V.   You can see examples of realistic package sizes vs capacitance + voltage in the references I gave.

[Rob Strand]

I was thinking you could measure the size of the part.  That would narrow things down and it would probably split any 2.2uF vs 22uF ambiguity.   Those zoomed in pics make it difficult for me to judge the scale of the caps.
(The reason there's still some hanging ambiguity is that one of the Vishay docs list 22uF 4V but not 2u2 4V.)

[AdrianM55]

I was thinking you could measure the size of the part.  That would narrow things down and it would probably split any 2.2uF vs 22uF ambiguity.   Those zoomed in pics make it difficult for me to judge the scale of the caps.
(The reason there's still some hanging ambiguity is that one of the Vishay docs list 22uF 4V but not 2u2 4V.)

Ok so I was having busy weekend with few ups and downs on repairs but I unsoldered this cap and indeed it was shorting the circuit.
Unfortunately when I try to measure it it's "open".
Tried to grab other one but space is so tight that I didn't wanted to risk damaging neighbouring components and gave up.
I even tried Roland but their reply was something like "we do not provide components", where I was asking for a specific value of a specific component.

So I reckon after all them great responses that this will be 22uf 4V Tantalum as I haven't seen 2.2@4V.

I will measure it tonight and post it here.

Ps.
A bit disappointed with Roland...

[Rob Strand]

So I reckon after all them great responses that this will be 22uf 4V Tantalum as I haven't seen 2.2@4V.

What you often see is different size packages offering different values.   Smaller parts offering smaller values and/or higher voltages.     Despite what you *can* get theres usually a smaller ranger of common sizes vs value + voltage.

The Samsung docs are offering both 2.2uF @4V and 22uF @ 4V in package "P" (2012) .   In another series they offer 2.2uF @ 4V in a larger package and 22uF @ 4V is larger packages still.

A bit disappointed with Roland...

They used to be extraordinarily helpful and you could by some components.  Maybe with all the cheap Chinese made stuff over the last 20 years they have had to strip-back some of their services.

It's pretty weird they didn't tell you the part value.  I'm sure they have that info.   They could have at least offered the service manual at a price.

[AdrianM55]

I was thinking you could measure the size of the part.  That would narrow things down and it would probably split any 2.2uF vs 22uF ambiguity.   Those zoomed in pics make it difficult for me to judge the scale of the caps.
(The reason there's still some hanging ambiguity is that one of the Vishay docs list 22uF 4V but not 2u2 4V.)