Choosing a transistor

[The Master]

Ok, so china has contaminated milk powder. Are you saying not to trust the transistor with chinese in the datasheet incase its substandard or did i completely miss the point?

"Will be the transitor better than the baby milk?"
Erm, i guess it will be because i dont think baby milk will turn LEDs on

[rmteo]

Get the manufacturer's datasheet here:
http://www.fairchildsemi.com/ds/MP/MPSA13.pdf

[The Master]

So the one that Luciano origionally linked to is for both of the 2 and says 500mA for the Collector Current. Ive just had a look at that datasheet and the one for MPSA14 from the same site and both of those say the Collector Current is 1.2A.

Have these transistors been upgraded at some point and rapid still has an old datasheet?

[skimask]

It has chinese in it.

Are you sure that's chinese? Or is it a manufacturer's logo?

[The Master]

Im not sure exactly. It could be japanese kanji. The datasheet Luciano linked to didnt have any of that. It says its for both but the second one has a completely different datasheet. Now the datasheets from www.fairchildsemi.com are completely different to both of them :O

[Luciano]

Hi,

If the quality of the datasheet reflects the quality of the product....
http://www.rapidonline.com/netalogue/specs/47-5512.pdf

Compare the above datasheet with the datasheet of the MPSA14 made by Philips Semiconductors.
http://www.nxp.com/acrobat_download/...s/MPSA14_7.pdf

* * *

Make sure you know who are the makers of the components you use.

Best regards,

Luciano

[The Master]

That makes sense.

So can you get the same component (with the same number) from more than one company then? I thought each company had their own numbering system even if they make components that do the exact same thing

[rmteo]

It varies from manufacturer to manufacturer. The Fairchild one is rated at 1.2A. This one from On Semiconductor is rated at 500mA:
http://www.onsemi.com/pub_link/Collateral/MPSA13-D.PDF

[Luciano]

Hi,

"Tru Semi" is Rapid Electronics which is not a semiconductor maker.
Try the URL www.trusemi.com and you will be linked to Rapid Electronics.

Is the quality OK?
Can Rapid Electronics test the quality of these products?
Does Rapid Electronics know the real makers of these semiconductors?

* * *

Is that a commercial project or just for your personal use?

Best regards,

Luciano

[The Master]

I found something similar when i went to the truopto site. All the datasheets linked to the rapid site.

I was hoping to sell these lights if they work well. The ones im making at the moment are just test versions and will only be for personal use as will the next few versions untill im confident they are working properly

I know rapid cant test the quality of all their products but they do tend to sell good quality components. If anyone complained about anything im sure they would investigate it straight away. I suppose the only real way is to buy a few and test them. Before selling any of these lights i will leave some turned on for a week or 2 constantly. Some doing PWM and some with all 4 colors on full brigthness. Might even leave some running in extreme conditions like hot/cold/wet etc

[Luciano]

Hi,

The only problem I can see is that your LED modules will
have to produce the same light intensity. This is going to be
important when the LED modules are mounted close to each
other and therefore you can compare the intensity of the light.
The quality of the used LEDs and components will make the difference.
Life duration of high efficiency LEDs is an important consideration.

Best regards,

Luciano

[The Master]

I think ill probably keep one of them turned off then and compare it with the ones ive been testing. Rapid say the LEDs im thinking about are very good quality, last a long time and are bright so i guess all i can do is test them to be sure.