help identify a component on star pcb

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robostud5000
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help identify a component on star pcb

i found some inexpensive warm white xp-e's on ebay, but the star board has a component on it that i don't recognize.  here is the link: 

http://www.ebay.com/itm/10pcs-Cree-XPE-Q3-LED-3-2-3-6V-Warm-White-for-Camping-Light-LED-Bulb-/180838096840

does anyone know what that component on the right side of the board is?

HKJ
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Looks like a capacitor and it looks like it is parallel with the led.

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robostud5000
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would you know what it is for?  would it be better to take it off or just leave it on there?  would it be better to transfer the emitter to a standard pcb?

HKJ wrote:

Looks like a capacitor and it looks like it is parallel with the led.

kramer5150
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I have never seen that before on a Cree emitter board... maybe a current limiting resistor?  I have seen some cheap 3AAA direct drive lights with SMT resistors  on the board to throttle current going into the LED.  thats the only thing I can think of.

Microa
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It is a ceramic capacitor to smooth off the pulse current from the output of the driver. Usually it is placed on the driver board instead of placing it on the star MCPCB. No harm done to keep it there unless you find it affact the response of the PWM of your driver.

PilotPTK
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Yup, Exactly right.  Ceramic cap, probably a few uF..

Unless you're using a REALLY fast switching regulator/PWM, it's not hurting anything at all.  Of course, as long as you're using a decent driver, it's not really doing anything good either...

 

PPtk

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lyonn
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That component looks like an MLCC capacitor. It was apparently added to aid in filtering ripple from the driver and perhaps to control RF interference.

PilotPTK
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lyonn wrote:

That component looks like an MLCC capacitor. It was apparently added to aid in filtering ripple from the driver and perhaps to control RF interference.

Multi Layer Ceramic Capacitor.. Yep, Kind of like we all said..

I am currently extremely busy with work. Please do not expect a response from me quickly. I will be dropping in as time permits, but the amount of time I can dedicate to responding to topics and PMs is very limited.

robostud5000
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thank you everybody.  i guess i'll go ahead and order them.