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Need help identifying capacitor value ??

C

cordless89

Junior Member
I beleive its a polarized cap, surface mount with the markings "B4U" with a dot beneath the 4. Value and/or any info needed.

Pic

Thanks in advance.
 

Are you sure thats a capacitor? Don't they usually have a voltage or value printed on them like '10u' or '10u16V' or something? It could be a SMT diode with the line indicating cathode. Identifying these tiny components is almost always difficult. Using a multimeter with capacitance measurement is probably the only way to know for sure.
 
No, I am not sure what it is. I just took at as a polarized cap. I found some literature on smt markings and the B=1.1 and 4=10-4 but the U is ??? Or maybe this is not a cap. Thanks.
 
That looks like a diode... they're usually black.

Capacitors are usually tan (ceramics), green/blue (polyester or mica), or yellow and sometimes black (tantalum).

The leads are a sure giveaway, though - surface mount caps usually have leads under the ends of the device to reduce inductance for decoupling.
 
Did a capacitance test with a Fluke and nothing registered so I am guessing you are right. If its a diode, what do you think the markings mean? Anyhow, thanks for the help.
 
The line would be cathode (negative side): current flows toward the line only.

Otherwise, it could be any kind of diode. Manufacturers don't have room for much so they have markings for parts in the same series.

If you want to replace it, you'd probably be fine getting as high of a voltage Schottky you could find in that package, though if you had the circuit I could figure out more specifically what was needed.
 
I rec'd a tape of 50 from Digikey by mistake. They were supposed to be some DIP motor drivers but they were in the package instead. CS said go ahead and keep them as they didn't what they were either. Just trying to figure out what they are so I can give them away. I don't do smt.
 
You're very good. Did a search on OnSemi's site and found it.

SCHOTTKY BARRIER
RECTIFIER
0.5 AMPERES, 40 VOLTS
SOD-123 Power Surface Mount Package

B4 is the Product Code
U is the Date Code
. is Pb Free Code

If anyone needs some of these (49) let me know. FREE
 
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