I am ready to build my circuit and am looking at 5mm LED's on Amazon. I would like to start with a kit with multiple colors, BUT then have the ability to buy individual colors when needed. Would prefer to NOT get the transparent LED's, ( how can you tell what color they are?). Also, do the transparent LED's produce good color?????

Any advice would be appreciated.

 

The clear case LED's I've bought from Amazon are "Super-Bright" LED's. The color is good. Here's a video of some I messed with. Some red, green and blue LED's.

 

When buying individual color LEDS:

The LTL-307 series is a solid, universal, and easily identified Through-Hole LED.

It features Colored Lens, 5mm diameter, notable cathode indentation on the plastic, as well as different lead lengths to provide additional polarity denotation.

They range around the specs a little bit, but typically fit the bill for 2 Vf, 10 mA test current LEDS.

Reverse voltage is 5V rated.

 

One possibility for you is to buy these. They are 5mm RGB LEDs with a common cathode. I purchased these and they are fine. Since you are concerned about the color, though could you explain the application? Is it for signaling, illumination, ???. It’s very hard ti help without enough information.

 

Although some people have to throw nasty comments about Tayda Electronics whenever I mention it, they have great prices on 5mm LEDs. I've always been satisfied with them and I've purchased thousands of them over the past 12 years to tutor students and help them with science fair projects. One student made an OPEN sign for his dads business and I see it at least once per week. It had about 350 LEDs and was built about 6 years ago so the LEDs do last.

No datasheets generally from Tayda but the red ones are super bright which allows them to be seen in daylight at under 5mA. They have the red or clear lens and both are the same brightness. Not bad for 2 to 3¢ each.
https://www.taydaelectronics.com/leds/round-leds/5mm-leds.html

 

Depending on your application, you may want diffused LEDs. If you're going to look at the LEDs (e.g., they are an indicator), you want diffused. Non-diffused are a point of light, projecting a cone of light that will make a spot on the wall 6' away....and leave you seeing spots if you actually look at it.

 

I am ready to build my circuit and am looking at 5mm LED's on Amazon. I would like to start with a kit with multiple colors, BUT then have the ability to buy individual colors when needed. Would prefer to NOT get the transparent LED's, ( how can you tell what color they are?). Also, do the transparent LED's produce good color?????

Any advice would be appreciated.

Whatever you buy, do some empirical checks on them.

Each LED color has different characteristics.

I bought a few boxes of these and they are great but the specs are minimal. To get a uniform brightness with several different color LEDs they each needed a slightly different series resistor, this was determined by "hand measuring" each of the colors to determine voltage/current characteristics needed to get uniformity in brightness.

I just looked at the box and can see I scribbled the current value at which reasonable brightness occurred for each color, those values cause all five colors seen together, to be perceived as approx. the same intensity by the human eye.

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From that it's easy to work out the right dropper resistor for each color when supplied from say 5v.

 

Would prefer to NOT get the transparent LED's, ( how can you tell what color they are?). Also, do the transparent LED's produce good color?????

For transparent, as in water clear, you just turn them on; either with a DVM, continuity tester, LED tester, test circuit, store them by part number, etc.

Transparent lenses, even colored, have a narrower viewing angle.

Be aware that if you buy LEDs from someone who doesn't know what they're doing, you won't get a manufacturer's part number, so won't know the exact specifications. These sellers are common on Amazon, eBay, Ali Express, etc. Even places like Tayda Electronics don't provide the manufacturer; though they do provide some specs, but not nearly enough (like whether the lens is clear or diffused).

 

A quick check at Tayda reveals that many of the LEDs do have datasheets available. You are much more likely to get a quality product from Tayda then Amazon, and when you order the same part number again, you'll receive the same parts.

 

More reputable sellers will provide all the information you need. From Jameco:

 

As does Tayda for many of their LEDs.

 

Whatever you buy, do some empirical checks on them.

Each LED color has different characteristics.

I bought a few boxes of these and they are great but the specs are minimal. To get a uniform brightness with several different color LEDs they each needed a slightly different series resistor, this was determined by "hand measuring" each of the colors to determine voltage/current characteristics needed to get uniformity in brightness.

I just looked at the box and can see I scribbled the current value at which reasonable brightness occurred for each color, those values cause all five colors seen together, to be perceived as approx. the same intensity by the human eye.

View attachment 268538
​

From that it's easy to work out the right dropper resistor for each color when supplied from say 5v.

If you obtain a datasheet for them, you can learn a lot more about their sweet spot

 

A quick check at Tayda reveals that many of the LEDs do have datasheets available. You are much more likely to get a quality product from Tayda then Amazon, and when you order the same part number again, you'll receive the same parts.

Always.... _always_ download a datasheet with any component you get, and save it. Such information can become obsolete, and if you have save it.... it's just wise. I've spent countless hours hunting down datasheets long after the fact for a purchase because the vendor no longer offers the product, or it is obsolete (yet I still have the components to use). I have thousands of datasheets now. And with every product I make, datasheets go into the engineering package with the design documentation when the engineering is done and filed.

 

More reputable sellers will provide all the information you need. From Jameco:
View attachment 268541

But ordering from Jameco yields whatever they have in stock as a Red LED today. That's why they have "Datasheet (current)" on their webpage. If you ordered last week and want the datasheet, good luck. You'll not know what 5mm LED you got last week. That has always been a problem with Jameco.

 

I recommend Tayda too. Buy from someone who actually specialized in electronics. Tayda has great prices and I'm sure you can find other stuff to spend money on. Shipping cost is low too.

 

Just to be clear, the RGB LEDs I have suggested above can be used as red, green, or blue but the cost is low enough that it doesn't matter if the other chips aren't used.

You could also set a unique color with resistors mixing R, G, and B.

 

Just to be clear, the RGB LEDs I have suggested above can be used as red, green, or blue but the cost is low enough that it doesn't matter if the other chips aren't used.

You could also set a unique color with resistors mixing R, G, and B.

But still 3x to 5x more than a single color LED from Tayda.