Complete Guide to Applying for LED Lamp Bead Samples: How to Apply, What to Apply for, and What to Test After Receiving the Sample

Almost all lamp bead manufacturers claim "free samples", but there are not many engineers who can actually use samples - someone applied for 10 pieces of each of three to five colors, and when they light up and look "pretty bright", they place bulk orders. It was only during mass production that color differences and dead lights were discovered, and not a single problem that should have been exposed during the sample stage was exposed.

This article clarifies three things:What information should be provided when applying for samples, what specifications should be applied for, and how to test after receiving the samples.

1、 Prepare these 5 pieces of information before applying for samples

The more specific the information given to the manufacturer, the closer the samples obtained are to mass production status:

1. Packaging and SizeFor example, 0805 patch/5mm straight insertion round head

2. Color and wavelengthDon't just say 'green', should you say 'pure green 520-525nm' or 'plain green 568nm'

3. Brightness requirementsIt is best to have a target value (such as ≥ 400mcd @ 20mA), otherwise it indicates that the application scenario requires the manufacturer to recommend the gear

4. Quantity and purposeSample verification: Generally, 50-100 pieces per model are sufficient (leaving enough for aging testing losses)

5. Special requirementsAnti sulfurization, low power consumption of 2mA, wide temperature range, vehicle specifications, etc., to be clearly stated at the time of application

One sentence template: "0805 pure green 520-525nm, brightness 400mcd level, used for industrial equipment indicator lights, requires narrow bin, apply for 100 pieces for verification. When manufacturers see such a demand, they will directly produce samples according to mass production standards.

2、 Sample list suggestion: Don't just apply for the "target model"

The smart way to apply ishorizontal comparison：

• Target Model+Adjacent brightness levelsOne copy each (to verify the effectiveness of reducing usage)
• Target color+Easy to confuse colorsOne copy each (such as pure green and plain green, orange and red, compared side by side with the naked eye)
• Application for dual color LED beadsOne copy each for co yin and co yang(Wiring verification polarity)
• When suspecting that the incoming material channels are chaoticIn suppliesAlso sent for testing and comparison together

Hongcheng Optoelectronics' sample policy: Regular models are free of charge, with 50-100 pieces per model and sent out within 1-2 days; Customized products (special wavelengths, special colloids) are evaluated before sampling, with a cycle of 3-7 days.

3、 After receiving the sample: 6 actual test items list

1. Lighting consistency (most importantly)

Randomly select 20 pieces, use the same board and 20mA driver, and light them up side by side: visually observe whether the brightness is uniform and the color is consistent. The light beads in the same bin should not show individual differences.

2. Sampling measurement of photoelectric parameters

Conditional use of an integrating sphere to measure IV and dominant wavelength; If there are no conditions, use a regulated power supply and a multimeter to measure the VF distribution. The VF dispersion of the same batch should be ≤ 0.1V.

3. Low current performance

Adjust to 2-5mA to light up: Poor quality LED chips light up unevenly or show dark spots under low current, while high-quality LED chips remain uniform. This must be tested for battery powered projects.

4. Welding tolerance

Perform reflow soldering (260 ℃/10s) or soldering with a soldering iron (320 ℃/3s) according to your actual process, and retest after soldering. There should be no dead lights, dimming, or yellowing of the gel.

5. High temperature lighting (mandatory for industrial projects)

The rated current should be continuously lit for 72-168 hours in an environment of 60-85 ℃, with a light attenuation of ≤ 2% and no yellowing of the colloid.

6. Static sensitive items (blue/green/white light must be tested)

Simulate human static contact with pins and retest - a regular test requires an ESD gun. The simple method is to rub synthetic clothing in a dry environment, touch the pins, and then light them up to observe if there are any hidden injuries or darkening.

4、 After confirming the sample, don't forget to lock two things

• Lock Bin fileAsk the manufacturer to include the corresponding grading parameters (wavelength Bin, brightness Bin, VF level) of the samples in the quotation, and mass production will be shipped according to the same grading
• Sample preservation and sealingBoth parties shall keep one sample for signature and sealing, which will serve as the benchmark for future receipt and acceptance

5 FAQ

Q: Is the sample free? Who will bear the shipping cost?

Regular model samples are free of charge, and shipping fees are generally paid on delivery or borne by the manufacturer (policies vary among factories, and both our regular model samples and shipping fees are free).

Q: Will the quality of samples and mass production be different?

Non standardized manufacturers do indeed engage in "sample selection and mass production water release". Identification method: The sample is required to be randomly selected from the normal production batch and the spectral data of that batch is requested.

Q: Do I need to provide company qualifications to apply for samples?

Legitimate manufacturers may simply register company information to avoid peer sampling, but do not require complex qualifications. Please provide the project name and application scenario.

6、 Summary

The correct posture for sample application:Apply with specific parameters, compare horizontally across multiple levels, conduct 6 actual tests upon receipt, and lock the bin for sample retention after confirmationThe sample stage takes three days, and the mass production stage saves three months.

Hongcheng Optoelectronics' full range of indicator light beads support free sample application (regular 50-100 pieces/type, sent out within 1-2 days), and a spectral grading data sheet is provided with the sample. Application method: 139 2571 4318 (same WeChat account), sales@led-hc.com Or simply report "Package+Color+Brightness+Quantity".