LTW-C235DSKF-5A Dual-Color SMD LED Datasheet - White and Orange Light - 20-30mA - 72-75mW - Technical Documentation

1. Product Overview

This document details the specifications of a high-performance dual-color Surface-Mount Device (SMD) LED. The component integrates two independent LED chips within a single package: one emitting white light and the other emitting orange light. This design is specifically intended for applications requiring multiple indication states or color-coded signaling from a compact space.

Wannan LED yana amfani da kayan semiconductor na ci-gaba. Farin haske yana fitowa daga guntu na tushen InGaN (Indium Gallium Nitride), yayin da hasken orange ya samo asali daga guntu na tushen AlInGaP (Aluminum Indium Gallium Phosphide). Wannan haɗin yana amfani da cikakken inganci da haske na tsarin kayan biyu.

Muhimman fa'idodin wannan samfurin sun haɗa da bin umarnin RoHS (Restriction of Hazardous Substances), an ayyana shi azaman samfurin kore, da kuma dacewa da tsarin samarwa na yau da kullun na yawan jumla. Yana amfani da kunshe na kayan murɗa da ya dace da na'urorin haɗawa ta atomatik, kuma an ƙididdige shi don dacewa da tsarin haɗa IR (Infrared) reflow, shine zaɓi mai kyau na layin haɗa PCB na zamani.

2. Cikakken Bayanin Ƙayyadaddun Fasaha

2.1 Matsakaicin Ƙimar Ƙididdiga

Yin aiki fiye da waɗannan iyakoki na iya haifar da lalacewa ta dindindin. An ƙayyade ƙididdiga a yanayin zafin muhalli (Ta) na 25°C.

• Amfani da Wutar Lantarki:White light: 72 mW, Orange light: 75 mW. Wannan ma'auni ya ayyana matsakaicin ƙarfin wutar lantarki da LED zata iya ɓarke a matsayin zafi a ƙarƙashin aiki na ci gaba.
• Kololuwar kwararar gaba:White light: 100 mA, Orange light: 80 mA. Wannan shine matsakaicin ƙarfin igiyar bugun jini da aka yarda (1/10 aikin cikakken lokaci, faɗin bugun 0.1ms), yana dacewa don ƙyalli mai ƙarfi na ɗan lokaci.
• Kwararar gaba ta DC:White light: 20 mA, Orange light: 30 mA. Wannan shine shawarar matsakaicin ci gaba da kwararar gaba don aiki na dogon lokaci mai aminci.
• Ƙarfin lantarki na baya:Duk launuka biyu 5 V ne. Yin amfani da ƙarfin lantarki na baya fiye da wannan ƙima na iya lalata LED junction. An hana aiki na ci gaba da ƙarfin lantarki na baya.
• Kewayon zafin jiki:Operating temperature: -20°C to +80°C; Storage temperature: -30°C to +100°C. These define the environmental limits for functionality and non-operational storage.
• Infrared soldering conditions:Withstands 260°C for 10 seconds, which defines its compatibility with standard lead-free reflow soldering profiles.

2.2 Halaye na Lantarki da na Gani

These are typical performance parameters measured at Ta=25°C and a test current (IF) of 5mA, unless otherwise specified.

• Luminous intensity (Iv):A measure of perceived light output. White: Min. 45.0 mcd, Typ. (unspecified), Max. 180.0 mcd. Orange: Min. 11.2 mcd, Typ. (unspecified), Max. 71.0 mcd. Intensity is measured using a sensor filtered to match the photopic response of the human eye (CIE curve).
• Viewing angle (2θ1/2):Both colors are approximately 130 degrees. This is the angle at which the luminous intensity drops to half of its peak value, defining the spread of the light beam.
• Forward Voltage (VF):The voltage drop when the LED is conducting. White light: typical 2.85V, maximum 3.15V. Orange light: typical 2.00V, maximum 2.40V. This is crucial for circuit design and current-limiting resistor calculation.
• Peak Emission Wavelength (λP):For the orange LED, the typical value is 611 nm. This is the wavelength at which the spectral power distribution is highest.
• Dominant Wavelength (λd):For the orange LED, the typical value is 605 nm. This is the single wavelength perceived by the human eye as representing that color, derived from the CIE chromaticity diagram.
• Spectral Line Half-Width (Δλ):For orange LEDs, typically 20 nm. This indicates the spectral purity or bandwidth of the emitted light.
• Chromaticity coordinates (x, y):For white LEDs, typical values on the CIE 1931 diagram are (0.3, 0.3). A tolerance of ±0.01 applies. These coordinates precisely define the color point of the white light.
• Reverse current (IR):At VR=5V, maximum 10 μA for both colors, indicating the extremely small leakage current when the device is reverse-biased within its limits.

Electrostatic Discharge (ESD) Precautions:LEDs are sensitive to electrostatic discharge. Proper ESD precautions, such as using grounded wrist straps, anti-static mats, and equipment, must be taken during handling to prevent potential or catastrophic damage.

3. Bayanin Tsarin Rarrabawa

Don tabbatar da daidaito a cikin samarwa mai yawa, ana rarraba LED bisa aikin su. Ana yiwa takamaiman rukunin rukunin kwayar alama akan marufinsa.

3.1 Rarrabawar Ƙarfin Lantarki na Gaba (VF) na LED mai haske Fari

Ana rarraba LED bisa ƙarfin lantarki na gaba a lokacin IF=5mA. Kowane matsayi yana da ƙimar sallama na ±0.1V.
- Mataki A: 2.55V - 2.70V
- Mataki B: 2.70V - 2.85V
- Mataki C: 2.85V - 3.00V
- Mataki D: 3.00V - 3.15V

3.2 Rarrabawar Ƙarfin Haskakawa (Iv)

White LED (at IF=5mA, each bin tolerance ±15%):
- Bin P: 45.0 mcd - 71.0 mcd
- Bin Q: 71.0 mcd - 112.0 mcd
- Bin R: 112.0 mcd - 180.0 mcd

Orange LED (at IF=5mA):
- Bin L: 11.2 mcd - 18.0 mcd
- Bin M: 18.0 mcd - 28.0 mcd
- Bin N: 28.0 mcd - 45.0 mcd
- Bin P: 45.0 mcd - 71.0 mcd

3.3 Rarrabawar Launi (Kala) na LED mai haske Fari

The white light color point is graded according to its chromaticity coordinates (x, y) on the CIE 1931 diagram at IF=5mA. Six grades (S1 to S6) are defined by specific quadrilateral regions on the chromaticity diagram. A tolerance of ±0.01 applies to the (x, y) coordinates within each grade. This ensures visual color consistency across different production batches.

4. Bincike kan Lakatunan Aiki

The datasheet references typical characteristic curves to graphically represent device behavior. Although the specific charts are not reproduced in the text, they typically include:

• Relative Luminous Intensity vs. Forward Current:Shows how light output increases with current, typically in a sublinear relationship, highlighting efficiency changes.
• Forward Voltage vs. Forward Current:Illustrates the diode's I-V characteristics, which are crucial for thermal management and driver design.
• Relative Luminous Intensity vs. Ambient Temperature:It illustrates that light output decreases as junction temperature increases, which is a critical factor in thermal design.
• Spectral Power Distribution:For an orange LED, this curve will show the light intensity emitted at each wavelength, centered at 611 nm with a half-width of 20 nm.

These curves are crucial for designers to predict performance under non-standard conditions (different currents, temperatures) and to optimize application circuits.

5. Bayanin Injiniya da Kunshewa

5.1 Lambar Kaya da Rarraba Fil

Part Number:LTW-C235DSKF-5A
Lens Color:Yellow (affects light diffusion and appearance when off).
Emitting Color and Pin Assignment:
- InGaN white LED chip: Connected to pins 1 and 2.
- AlInGaP orange LED chip: Connected to pins 3 and 4.
This 4-pin configuration allows independent control of the two colors.

5.2 Girman Kunshewa

This LED conforms to the EIA (Electronic Industries Alliance) standard SMD package outline. All dimensions are in millimeters, with a standard tolerance of ±0.10 mm unless otherwise specified. The datasheet includes a detailed dimensional drawing showing the package length, width, height, lead pitch, and other key mechanical features critical for PCB pad design.

5.3 Girman Fil ɗin Gwangwani da Ake Shawarwari

Recommended PCB pad layout is provided to ensure reliable solder joint formation during reflow soldering. Adhering to these dimensions aids in proper solder fillet formation, mechanical stability, and thermal relief.

6. Soldering, Assembly, and Handling Guidelines

6.1 Soldering Process

This device is fully compatible with infrared (IR) reflow soldering processes. A recommended reflow profile is provided, with a peak temperature condition of 260°C for 10 seconds, meeting common lead-free solder requirements. Following the recommended profile is crucial to prevent thermal damage to the LED package or die.

6.2 Cleaning

If post-solder cleaning is required, only specified chemicals should be used. Unspecified solvents may damage the epoxy lens or package. The recommended method is immersion in ethanol or isopropyl alcohol at room temperature for a duration not exceeding one minute.

6.3 Storage Conditions

Sealed package (with desiccant):Store at ≤30°C and ≤90% relative humidity (RH). The shelf life under these conditions is one year.
Opened package:Components must be stored at ≤30°C and ≤60% RH. It is strongly recommended to complete the IR reflow soldering process within one week after opening the moisture barrier bag.
Long-term storage (opened):For storage exceeding one week, place the components in a sealed container with desiccant or a nitrogen dry cabinet.
Re-baking:LEDs stored outside the original packaging for more than one week require baking at approximately 60°C for at least 20 hours before soldering to remove absorbed moisture and prevent "popcorn" effect (package cracking) during reflow.

7. Kunshe da Bayanin Oda

7.1 Siffofin Nadar Kirtani

LEDs are supplied in embossed carrier tape with protective cover tape, wound on 7-inch (approx. 178 mm) diameter reels. This packaging complies with the ANSI/EIA 481-1-A-1994 standard.

• Quantity per reel:3000 pieces.
• Remaining Minimum Order Quantity (MOQ):500 pieces.
• Cover tape:Empty pockets in the carrier tape are sealed with cover tape.
• Missing components:The maximum number of consecutive missing components allowed on the reel is two.

The datasheet provides detailed dimensional drawings of the carrier tape (pocket size, pitch, etc.) and the reel (hub diameter, flange diameter, etc.) to ensure compatibility with automatic assembly equipment.

8. Bayanin Aikace-aikace da La'akari da Zane

8.1 Amfanin Da Ake Tsammani

This LED is designed for use in standard electronic equipment, including office automation equipment, communication equipment, and household appliances. For applications requiring extremely high reliability where failure could endanger life or health (e.g., aviation, medical systems, safety equipment), specific consultation and qualification are required prior to design adoption.

8.2 Circuit Design

• Current Limiting:Each color of LED must use an external current-limiting resistor. The resistor value (R) can be calculated using Ohm's Law: R = (Supply Voltage - VF) / IF, where VF is the forward voltage of the specific color/batch, and IF is the desired operating current (must not exceed the DC forward current rating).
• Thermal Management:Although power consumption is low, ensuring sufficient PCB copper area or thermal vias helps maintain a lower junction temperature, thereby preserving light output and lifespan.
• Parallel/Series Connection:Due to variations in VF, directly connecting LEDs in parallel is generally not recommended, as it may cause current imbalance. For uniform brightness, a series connection sharing a single current-limiting resistor is preferred.

8.3 Typical Application Scenarios

• Status Indicator:Dual-color function allows multiple statuses (e.g., white light = on, orange light = standby, dual-color = warning).
• Keyboard or icon backlight:Backlight in different colors is optional.
• Consumer electronics:Indicators for power, connection, or mode in devices such as routers, chargers, or audio equipment.
• Automotive interior indicators:(If certified for specific application environments).

9. Technical Comparison and Differentiation

This dual-color LED has distinct advantages in specific applications:

• Compared to two single-color LEDs:Saves PCB space, reduces mounting time/cost (one component vs. two), and ensures precise mechanical alignment of the two light sources.
• Material Technology:Utilizes optimized chip materials (InGaN for white light, AlInGaP for orange light) to achieve high efficiency and brightness in their respective spectra, rather than using potentially less efficient phosphor-converted orange light.
• Reverse Mount Design:Mentioning "reverse mount" indicates a package design where the primary light emission is through the substrate or a specific direction, which can be advantageous for certain optical designs compared to standard top-emitting packages.

10. Frequently Asked Questions (FAQ)

Q1: Can I drive both the white and amber LEDs at their maximum DC current simultaneously?
A1: Yes, but the total power dissipation on the package must be considered. Driving the white at 20mA (~2.85V=57mW) and the amber at 30mA (~2.00V=60mW) totals ~117mW, which exceeds their individual power ratings (72mW, 75mW). Operating at full current simultaneously may require derating or enhanced thermal management to keep the junction temperature within safe limits.

Q2: What is the difference between Peak Wavelength and Dominant Wavelength?
A2: Peak Wavelength (λP=611 nm) is the physical wavelength at which the LED emits the most optical power. Dominant Wavelength (λd=605 nm) is a perceptual metric; it is the wavelength of monochromatic light that has the same color as the LED's output for a standard human observer. They are often different, especially for saturated colors.

Q3: Why are the storage humidity requirements stricter after the bag is opened?
A3: The sealed bag contains desiccant to maintain a very low humidity level, protecting the LEDs from moisture absorption. Once opened, the components are exposed to ambient humidity. Moisture absorbed by the plastic package can rapidly expand into steam during high-temperature reflow soldering, potentially causing internal delamination or cracking ("popcorn" effect).

Q4: How to understand the binning codes when ordering?
A4: Domin don samfurin ya yi daidai, yakamata ka ƙayyade VF, Iv, da kuma rarrabawar launi da ake buƙata lokacin yin oda. Misali, za ka iya neman "LTW-C235DSKF-5A, matakin VF B, matakin Iv farin haske Q, matakin Iv lemu haske M, matakin launi S3". Wannan yana tabbatar da cewa duk LED ɗin da ke cikin rukunin samarwa suna da halayen lantarki da na gani masu kama da juna sosai.

11. Misalin Nazarin Shari'ar Zane

Yanayi:Ɗora alamar yanayi don sauya hanyar sadarwa, tana da yanayi guda uku: kashewa, aikin hanyar haɗi (farin haske) da canja wurin bayanai (lemu haske yana ƙyalkyalo).
Aiwatarwa:Amfani da LTW-C235DSKF-5A guda ɗaya. Microcontroller (MCU) yana da filayen GPIO guda biyu, kowannensu yana haɗuwa da launin LED ta hanyar resistor mai iyakancewar kwarara.
Lissafi:Amfani da wutar lantarki 3.3V, manufar kwarara ita ce 10mA, don samun kyakkyawan ganuwa da kuma adana ƙarfin wuta.
- For white light (VF~2.85V): R = (3.3V - 2.85V) / 0.01A = 45 Ω. Use a standard 47 Ω resistor.
- For orange light (VF~2.00V): R = (3.3V - 2.00V) / 0.01A = 130 Ω. Use a standard 130 Ω or 120 Ω resistor.
PCB Layout:Use the recommended pad layout. Maintain a small keep-out area under the LED to prevent solder wicking. The MCU firmware controls the pins to achieve the desired steady and blinking states.
Results:Using only a single component footprint, a compact, reliable, and clear multi-state indicator is achieved.

12. Yadda Ake Aiki

An LED is a semiconductor diode. When a forward voltage exceeding the chip's bandgap energy is applied, electrons and holes recombine in the active region, releasing energy in the form of photons (light). The color of the light is determined by the bandgap energy of the semiconductor material. InGaN material has a wider bandgap, enabling emission in the blue/violet/ultraviolet range; white light is typically generated by coating a blue InGaN chip with yellow phosphor, mixing the light to appear white. The bandgap of AlInGaP material is suitable for direct emission in the red, orange, amber, and yellow parts of the spectrum, as used in the orange chip of this device. The dual-chip package electrically isolates the two semiconductor junctions, allowing them to be controlled independently.

13. Trends na Fasaha

Optoelektronik endüstrisi sürekli gelişmektedir. Bu iki renkli LED ile ilgili trendler şunları içerir:
Verimlilik Artışı:İç kuantum verimliliği ve ışık çıkarma teknolojilerindeki sürekli iyileştirmeler, aynı veya daha düşük sürücü akımında daha yüksek ışık şiddeti (mcd) elde edilmesine yol açarak sistem enerji verimliliğini artırır.
Küçültme:Bu ürün standart paket kullanmasına rağmen, endüstri yüksek yoğunluklu elektronik ürünlere uyum sağlamak için (toplam ışık çıkışı veya ısı dağılımından ödün verme pahasına da olsa) daha küçük paket boyutlarına (örneğin 0402, 0201 metrik) doğru sürekli bir itiş göstermektedir.
Renk Tutarlılığı ve Sınıflandırma:Epitaksiyel büyüme ve üretim kontrolündeki ilerlemeler, VF ve kromatiklikteki doğal varyasyonu azaltarak daha sıkı sınıflandırma dağılımları sağlamakta, geniş sınıflandırma ihtiyacını azaltmakta veya envanter yönetimini basitleştirmektedir.
Integrated Solution:The trend of integrating LED driver ICs (constant current source, PWM controller) directly with LED packages or modules simplifies end-circuit design. This specific component remains a discrete, driverless LED.
Reliability and Lifetime:Continuous improvements in packaging materials (epoxy, silicone) and chip-attach technology enhance long-term reliability, lumen maintenance, and resistance to thermal and environmental stresses.