Maker Pro
Maker Pro

Surface Mount Part Identification - TC

Leigh Green

Jul 10, 2017
4
Joined
Jul 10, 2017
Messages
4
I have a Part on a board which normally takes 5v DC and I accidentally supplied 12v. It looks to me to be a capacitor and based on where it sits in the circuit, namely right after a voltage regulator, but according to general terminology TC stands for TermoCouple.
Can Anyone please identify the blown Part in the image Attached:
20170710_224652.jpg I am 99% sure it is the same as the other 2 components of same size. The code on them reads as 107A 1542 - but I can't find any reference anywhere else on what these might be.
More importantly I need to get replacements ASAP to get this device back up and running (hoping of course that no other component is also fried...
 

kellys_eye

Jun 25, 2010
6,514
Joined
Jun 25, 2010
Messages
6,514
Since TC1 and TC2 are similarly notified - and they are both capacitors of 10μF - it follows that TC4 will be the same - a capacitor, the value of which is indeterminable but would likely be the same at the others.

If this is the case the you need to be aware that they are polarised and that replacement requires correct orientation too.

But you have other problems in that U3 above them is also (or appears to be) frazzled.....
 

Leigh Green

Jul 10, 2017
4
Joined
Jul 10, 2017
Messages
4
Thanks for that. Yeah i figured Tantalum at one point...but TC didn't match a pcd conponent term list I was finding...
So...ok i get 10uf that makes sense 10 and 7 zeros.
Voltage... i guess 6.3v on the basis of it being the common value for tantalum like 10v, 16v
 

Leigh Green

Jul 10, 2017
4
Joined
Jul 10, 2017
Messages
4
I think the UC caught spray from the TC blowing...but will check it anyway. Many thanks
 

kellys_eye

Jun 25, 2010
6,514
Joined
Jun 25, 2010
Messages
6,514
Could be that the capacitor being 6.3V (intended for a 5V input max) blew its guts due to the 12V application. Sure the 12V was the same polarity as the 5V though.... probably was but worth checking.
 

Leigh Green

Jul 10, 2017
4
Joined
Jul 10, 2017
Messages
4
@kellys_eye No the polarity was correct - it is two separate DC power plugs coming out of an ATX Power supply, I accidentally switched them in my hand before plugging in and turning on, so the 12v went in the wrong device and 5v into another, etc.
I have worked out the following - and wouldn't mind a confirmation:
According to what I read here: http://www.radio-electronics.com/info/data/capacitor/capacitor-markings.php
the markings for the Tantalum SMD saying 107A means it is a 10Volt, 100uf - i.e. 10 to the 7 zero multiplier
The IC appears to be similar but not identical to the other one on-board, it is an AMS1117-3.3 SOT223 - which is a 3.3v Voltage regulator, as opposed to the other similar which is adjustable - Similar to an LM317.

My bigger question now is - since I am struggling trying to find an appropriate rating Tantalum that I can get quick - can I just replace it with an Electrolytic of similar values - or the alternative which I can get hold of which is Tantalum 100uf at 16v.
I know generally the Electrolytic could have higher ESR - but will cross that bridge if and when I come to it...
 

davenn

Moderator
Sep 5, 2009
14,254
Joined
Sep 5, 2009
Messages
14,254
My bigger question now is - since I am struggling trying to find an appropriate rating Tantalum that I can get quick - can I just replace it with an Electrolytic of similar values - or the alternative which I can get hold of which is Tantalum 100uf at 16v.

yeah .... just use 10uF 16V electros in the mean time -- no problems there
 

kellys_eye

Jun 25, 2010
6,514
Joined
Jun 25, 2010
Messages
6,514
...as above.

Tants are usually used 'generically' for their compact size - except in those situations where tant capabilities are 'required' (10 times lower ESR than equivalent electrolytics) but for the DC side of a power supply (pre-chopper etc) you'll get away with practically anything that fits!

Their downfall is, as you've discovered, their spectacular failure mode!
 

(*steve*)

¡sǝpodᴉʇuɐ ǝɥʇ ɹɐǝɥd
Moderator
Jan 21, 2010
25,510
Joined
Jan 21, 2010
Messages
25,510
There is a capacitance limit for ceramic caps

Yeah, I was impressed when I saw the first 1μF SMD ceramic.

Then I was impressed when I saw 10μF.

After seeing 100μF, I had learned to expect the unexpected and vowed not to be impressed until I see 1000μF.

I'm almost impressed again.
 
Top