The Precautions Of Driver Circuit Design Matters

 Because LED is a constant current driven electronic component, it is known from the characteristic curve of LED I-V that when the voltage changes slightly, the current passing through the LED will change greatly, which may cause the uneven current flowing into LED. Therefore, LED circuit design is not allowed to use the constant voltage way to drive. If the constant voltage drive is unavoidable, it is best to use the following (B) circuit. Because the difference in the positive voltage of each LED in the (A) circuit may cause the current flowing into the Ultraviolet LED Lamp Chips to be uneven. In addition, it is necessary to measure whether the current through the LEDs is within the working current range of the standard specifications during product design and trial production.

1.Please use forward current to drive Ultraviolet Light Emitting Diode. Do not apply voltage to the product in the positive or negative direction when the product is not in use. In particular, do not apply voltage to the product continuously in the negative direction. This may lead to ion migration and damage to the LED. If the product is not used for a long time, in case of emergency, the main power supply should be turned off.

2.Because the test current of LED with different power will be inconsistent, it is necessary to read the product specification in detail when using Ultraviolet LED, and it is advisable to use the standard not exceeding the scope of specification identification. Because LED is an electronic component, the internal resistance of LED is caused by the change of ambient temperature. Therefore, the specifications and parameters of our company’s related products are tested under the condition of 25 ℃ at room temperature.

3.(i.e. AC to DC product). In the current conversion process, there may be a pulse signal, high voltage pulse signal will cause damage to the UV LED P/N junction, resulting in the LED failure. Therefore, the voltage fluctuation we allow is within 2%.

4.When test power supply is used for spot measurement and inspection of semi-finished products, the no-load voltage of the test power supply should be paid attention to. In general, the no-load voltage is required to be lower than actual demand voltage of the load, so as not to damage the UV LED Light Beads due to the high no-load voltage of the power supply and any over-voltage of the load at the moment of point measurement.

5.Different voltage products can not be applied to the same parallel circuit, which will increase the LED voltage drop difference and lead to a large difference in the current passing through a single LED, which will affect the radiation flux and reliability of Ultraviolet LED Light Chips, and will cause burnout and failure in serious cases.

(Note: current limiting measures are necessary, otherwise a slight voltage change will cause a large current change, which may cause LED failure.)

UV LED Storage Precautions

 1.When the product is heated during welding, it may cause the moisture absorbed in the package to evaporate and expand, thus causing the interface of the outer package to crack and affecting the optical properties of the lamp bead. Therefore, in order to control the moisture absorption before welding installation in the minimum, our company adopts moisture-proof packaging.

2.After opening the aluminum moisture-proof product bag, it must be kept under the storage condition (after opening the aluminum moisture-proof product bag) until the welding installation is completed. If there is product surplus must be kept in a desiccant sealed container, etc., it is beat to reseal preservation.

3.If the shelf life is exceeded, the Ultraviolet LED Light Beads must be baked.

4.The electrode of this product is gold-plated. If it is exposed to the environment containing corrosive gas, the gold-plated surface may deteriorate, which affect the welding strength. This product must be kept in a sealed container after opening.

5.Do not use materials containing sulfur in products (gasket, adhesive, etc. may contain sulfur). Abnormal coating surface may lead to poor contact, affecting the power of the product. If you need to use gaskets, it is best to use silicone gaskets. Note, however, that low molecular siloxane may cause poor exposure.

6.This product should be stored in a place with little temperature change, because condensation may occur in places where temperature changes are dramatic.

7.Do not store in dusty environment.

8.Prolonged exposure to the environment that may be exposed to direct or higher than room temperature is prohibited.

Condition		Temperature	Humidity	Time limit
Storage	Before opening the aluminum moisture-proof product bag	Under 30°	Under 80% RH	One year after delivery
	After opening the aluminum moisture-proof product bag	Under 30°	Under 60% RH	168 hours
Bake		65±5°	-	Over 24 hours

What should we pay attention to when using UV LED?

1.When using this product, attention should be paid to water (water vapor / condensate), dust, harmful volatiles (such as sulfur, halogen, etc.) and other pollutants.

2.The glass parts of UV Light Emitting Diode are fragile. Please do not press the glass parts.

3.After the product is welded, rework should be avoided as far as possible, which may lead to the performance degradation or even failure of the product.

4.Avoid pressing the product during welding.

5.If it is necessary to use flux, the flux shall comply with ROHS, and halogenated flux shall not be used.

6.This product should not directly contact with water or some chemical substances, such as oil, organic solvents, etc., otherwise it will cause rust or failure of the product. In particular, when the product is in use, it should be guaranteed that the product and the substrate are dry without condensation water. When cleaning is required, use a dust-free cloth dipped in alcohol to gently wipe the product.

7.If customer does not have alcohol and need to use other chemicals to clean this product, he/she must ensure that these chemicals will not dissolve or corrose the product.

8.When the product is in working condition, the pin / pad temperature of the product should be measured, and the pin / pad temperature should be controlled below 55 ° to ensure that the product works in a safe junction temperature. If the pin / pad temperature is excessive, it will result in failure of the product.

What are the Consideration for UV LED packaging?

1. Ultraviolet light emitted by UV LED Lamp Beads has a great impact on some materials, such as rubber materials, which will damage to a certain extent. In long-term irradiate process, can accelerate the aging of wire. The light emitted by UV LED is transferred into heat after being absorbed by the material, and will even scorch the rubber, which may cause a short circuit. This requires us when designing, must undertake protection to wire part. Above all, we should choose fireproof material to serve as the outer protection of wire, wire must be protected when designing next, avoid to be irradiated by ultraviolet light. The assembly materials should be used as little as possible with polyethylene and other organic materials.

2. In the process of cutting the circuit board after the circuit board is installed, the bending of the circuit board may cause the outer package to break. Therefore, when deciding the LED configuration, the LED stress in the circuit board winding and twisting should be minimized as far as possible.

3. In the circuit board cutting, the mechanical stress of UV LED Lights is related to its installation position, so when equipped with LED, the LED should be in the position where it is least susceptible to mechanical stress.

4. Avoid manual operation in circuit board cutting.

5. If the aluminum circuit board is used for installation, make sure that the tin crack will not occur due to the thermal stress in use.

How Does UV LED Prevent Static Electricity?

 1. The product is sensitive to static electricity and surge voltage, and the chip may be damaged under the impact of static electricity and surge voltage, which will affect the reliability of the product. Therefore, the following anti-static countermeasures should be used in operation.

Use antistatic bracelet, conductive clothing, conductive shoes, conductive floor, etc. to remove the charge

Ground the devices, tools, etc. in the operating area to remove the charge

Working tables and warehouse shelves made of conductive materials, etc.

2. Properly ground all tools, equipment, fixture, etc. that need to be grounded in the operating area. In addition, the module or product after installation of this product also needs to implement surge voltage countermeasures.

3. If there are insulators such as glass or plastic used in tools and devices, the following anti-static measures shall be used.

Use conductive materials to conduct electricity

Humidification to prevent static electricity

Use an ion generator to neutralize charge

4. It is better to check whether the static damage is carried out when the product is installed in the characteristic inspection after the template is installed.

5. In a good electrostatic safety area, the relative humidity condition should be 50% ± 10%, and the humidity in general factory operation area should not be lower than 40%. If less than 40%, using ion neutralization equipment or humidifier can be considered.

6. The table equipment and tools are grounded, and the antistatic table / shelf cushion is made of conductive materials.

7. Before using this product, the customer should confirm whether the product has been damaged by static electricity in the following methods : using a small forward current (e.g. 1mA) to test the forward voltage of the product. If the detected voltage value is lower than the voltage value corresponding to the detected current in the IV curve of the product, the product is likely to be damaged by static electricity.

Eye safety

1.Before trying to light up the product, please take protective measures for eyes, such as wearing sunglasses. Ultraviolet light has irreversible damage to the human eyes. Please do not gaze directly at the ultraviolet light with naked eyes.

2.Don’t look at ultraviolet light for a long time even if you are wearing UV protective glasses.

Take You To Know PCB Substrate

 High performance hard organic PCB substrate usually consists of dielectric layer (epoxy resin, glass fiber) and a high purity conductor (copper foil). We evaluate the parameters related to the quality of printed circuit board substrate, mainly including glass transition temperature Tg, thermal expansion coefficient CTE, heat-resistant decomposition time and decomposition temperature Td of substrate, electrical performance, PCB water absorption, electrical mobility CAF and so on.

Generally printed circuit board substrate can be divided into two types : rigid substrate materials and flexible substrate materials. The important type of general rigid substrate material is copper clad plate.

According to PCB board reinforcement materials are generally divided into the following types :

1.Phenolic PCB Paper Substrate

Because this PCB is composed of paper pulp, wood pulp, etc., it is sometimes also known as cardboard, V0 board, flame retardant board, 94HB, etc. Its main material is wood pulp fiber paper, through the phenolic resin pressure and synthesis of a PCB board.

Characteristics : don’t fireproof, can be punched processing, low cost, cheap price, relatively small density.

2.Composite PCB Substrate

This is also known as powder board, with wood pulp fiber paper or cotton pulp fiber paper as the reinforcing material. Glass fiber cloth is also used as the surface reinforcement material. Both materials are made of flame retardant epoxy resin.

There are single-side semi-fiberglass 22F, CEM-1 and double-side semi-fiberglass CEM-3, among which CEM-1 and CEM-3 are the most common composite substrate copper clad panels at present.

3.Glass Fiber PCB Substrate

Sometimes it is also called epoxy board, glass fiber board, FR4, fiberboard, etc. It is made of epoxy resin as a binder and glass fiber cloth as a reinforcing material.

Characteristics : high working temperature, little environmental influence, often used in double-sided PCB board.

4.Other PCB Substrate

In addition to the three commonly seen above, there are also metal substrates and BUM.

Sub-base material technology and production, has experienced half a century of development, the world’s annual output has reached 290 million square meters. This development moment is driven by the innovation and development of electronics complete machine products, semiconductor manufacturing technology, electronics installation technology and printed circuit board technology.

China’s substrate material industry after 40 years of development, has formed an annual output value of about 9 billion yuan of production scale. In 2000, the total output of China’s mainland copper clad plates has reached 64 million square meters, creating an output value of 5.5 billion yuan. Among them, the output of paper-based copper-clad plate has ranked third in the world. But in the technical level, product variety, especially in the development of new substrate, there is a considerable gap with foreign advanced countries.

Solidified Camera Module, Installed Surveillance Camera

 Some camera module manufacturers used UV lamp irradiation curing before, the time is longer. In addition, the surface temperature of the camera assembly is higher after irradiation, which seriously affects the quality of their products. Therefore, they found us, Shenzhen Deshengxing Electronics Co., Ltd., to conduct special product testing.

We knew that, in the production process of the security surveillance camera module, we need to use UV glue to fix the filters, lenses, CMOS components, etc. Because of using UV glue bonding, and the requirements of camera module is relatively high, it needs to use matched UV LED curing light source for curing and drying. And, because the volume of camera module is relatively small, we have given priority to choose Shenzhen Deshengxing Electronics Co., Ltd. UV LED Spot Light Source Equipment for product testing.

(overall / individual control)

After a series of comparative tests, the customer choose a custom UV LED spot light source equipment here for the curing UV glue. According to the test results, the surface temperature of the UV glue does not rise more than 5 ℃ after 5-10 seconds of UV irradiation, and the use of ordinary natural cooling irradiation head can meet the use requirements. Combined with actual using situation, we chose 1+4 UV LED spot light source curing machine to test. LED UV Curing Machine from Shenzhen Deshengxing Electronics Co., Ltd. not only greatly saves the curing time, but also the temperature of the camera module parts does not change basically. The curing effect of the UV glue is particularly good, which effectively solves the problems encountered by customers and achieves long-term cooperation opinions.

(1) medical products  (2) electronics  (3) components fixed

(4) LCD pre cured  (5) camera module

(1) DVD/CD lens bonding irradiation

(2) lens and filter bonding irradiation

(3) digital lens IC bonding irradiation

(4) lens scoring bonding irradiation

(5) LCD/DLP optical

(6) liquid crystal main inlet seal and OLB enhancement

(7) small prism bonding

(8) hard disk, magnetic head bonding irradiation

(9) after core-adjusting, fiber optic connector parts bonding irradiation

(10) optical fiber color bonding irradiation

(11) photo-electric switch/special shaped parts bonding irradiation

(12) earphone voice coil bonding irradiation

(13) miniature motor parts bonding irradiation

(14) medical products bonding irradiation

(15) injecting needle fixation bonding irradiation

(16) compound bonding irradiation

Portable 5W 395nm UV Flashlight Curing Lamp USB Charging Detection Light

 USB Chargeable UV Flashlight 395nm is made with 5W high power UV LED light beads, which the lifetime can reach 100000 hours. This kind of 395nm UV LED Flashlight is simple operation, small and easy to carry. It not only can be used in curing glue, also can be used in detection and discrimination.

Parameters : 

Brand : DSXUV

Name : UV Flashlight Curing Lamp

Type : DSXUV-9200395

Material : aluminum alloy, waterproof and moisture-proof

Light source : UV LED Lamp Beads

Wavelength : 395nm

Size : 93*26mm

Charge : USB charge

Type : strong light, weak light, flash light

Weight : 70g

Telescopic focusing design (adjust the irradiation range according to the use requirements)

Stretch the lamp head forward manually

Compatible with various charging modes : 

1. Charging by charger

2. Notebook charging

3. Charge the battery

Fast, stable and convenient, built-in high capacity battery

USB plug direct charge, hidden plug

Usage : 

1.Prepare the objects to be bonded, shadowless glue, and ultraviolet flashlight curing light

2.Drop the glue on the sticky material (2-3 drops)

3.Fit the glass sheet onto the aluminum sheet with the glue dripping, and press it flat

4.Shine UV light for about 3 seconds, and make preliminary positioning

5.Check whether the position is correct, if not, it needs to be re-bonded

6.For a good position, use UV flashlight curing lamp until curing

7.Wide up the spilled glue with a wet towel

8.Bonding finished

Suitable for testing a variety of items : 

1. Check the authenticity of the bill

2. All kinds of stealth security code

3. Fluorescent detection

4. According to the jade

5. Grasp the scorpion

6. Green oil and UV glue curing

7. Famous anti-counterfeiting

8. Tobacco security

9. Jade anti-counterfeiting