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I'm taking apart some old electronics, and I see an inductor with the following on the label:


Here's a photo:

enter image description here

I searched online but what I found was that there should be three digits: two for the μH and one for a multiplier. Eg: 432 would mean 43 μH, with a 10^2 multiplier, so 4300 μH. But I found nothing about 4 digits, or those other characters. What do they mean?

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Can you post a photo? – Oli Glaser Dec 5 '12 at 4:32
Sure. I just did. – Rob N Dec 5 '12 at 12:48
Then I guess we should have specified a focused photo. – Olin Lathrop Dec 5 '12 at 12:50
That's hard to do in my current light situation. What details are you looking for? I thought the photo did enough to show the label, and the basic shape and style of the inductor. – Rob N Dec 5 '12 at 12:56
(It's focused on the label and the back is out of the depth of field, which is small at close range.) – Rob N Dec 5 '12 at 12:59
up vote 6 down vote accepted

22µH, 2.5A inductors Coilcraft TV1415-B or Transpower Technologies, Inc. LCI-1

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+1, good detective work. – Anindo Ghosh Dec 5 '12 at 9:03
Thanks. How do I find that myself? – Rob N Dec 5 '12 at 12:59
I just copy and pasted and found it in seconds. Let me try again so see how I did it.. I tried Bing.. same thing bit.ly/TFrUiJ It was in an application note BOM 1st hit .. 10 seconds... the datasheet.com site sometimes misses, but has good resources – Tony Stewart Dec 5 '12 at 15:34
www.datasheetarchive.com rather.. I generally avoid all sites from Brokers who sell parts and use spaces where needed if there are no hits. – Tony Stewart Dec 5 '12 at 15:42
I forgot to mention, my eyes glance over and ignore almost all Google ad. hits at the top. and then ignore any date code numbers near the bottom of the part like 9842 in yyww format.. there are few more tricks I use but like magicians I forgot to tell you... comes with experience since the 70's – Tony Stewart Dec 5 '12 at 15:49

The above post is incorrect.

Since there are 4 digits the 4th digit becomes the multiplier. The letter suffix represents the tolerance a.k.a the possible deviation from the printed value.

A=+/-.05% B=+/-.1% C=+/-.25% D=+/-.5% . . . M=+/-20%

1415-B is 14,100,000 uH about 14.1H B=+/-0.1% tolerance. If it were serface-mount 14,100,000 nH about 14.1uH with same tolerance.

Tips: *Be careful that it isn't a product number. *Full sized inductors are always marked in uH (Micro-Henry) = 1/1,000,000H *SMT version of the same inductors are marked in nH (Nano-Henry) = 1/1,000,000uH

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It's hard to judge size from a photo but unless the writing is huge it looks too small for a 14.1H, plus can you find anyone that sells one with that high value and a 0.1% tolerance? – PeterJ Jun 1 '14 at 6:33
@Alex: micro = 1/1 000 000, nano = 1/1 000 000 000. – EM Fields Jun 1 '14 at 7:01
You say "be careful that it isn't a product number". If you google the "TV1415-B" you do find a datasheet where it seems to me it's mentioned as a product. Do you see that datasheet? As for size, the circular face with the writing is about half the diameter of a penny. – Rob N Jun 1 '14 at 12:36

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