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SMD LED 黃綠光 120度視角 - 封裝尺寸 - 順向電壓 2.0V 典型值 - 功耗 72mW - 繁體中文技術規格書

一款採用擴散式透鏡的黃綠光 SMD LED 技術規格書,詳細說明發光強度、視角、順向電壓、分級代碼、封裝尺寸及建議焊接溫度曲線等規格。
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PDF文件封面 - SMD LED 黃綠光 120度視角 - 封裝尺寸 - 順向電壓 2.0V 典型值 - 功耗 72mW - 繁體中文技術規格書

1. 產品概述 本文件詳細說明一款採用表面黏著技術 (SMD) 的發光二極體 (LED) 規格。此元件使用擴散式透鏡及 AlInGaP (磷化鋁銦鎵) 半導體材料來產生黃綠光輸出。該元件專為自動化印刷電路板 (PCB) 組裝製程設計,適用於大量生產。其緊湊的外型尺寸及與標準 SMD 貼裝設備的相容性,使其能滿足各電子領域中空間受限的應用需求。

1.1 核心特性與優勢

法規符合性: 產品符合相關環境法規 (例如:RoHS)。

2. 深入技術參數分析 以下章節提供對定義元件性能範圍的關鍵電氣、光學及熱參數的詳細客觀解讀。

2.1 絕對最大額定值 這些額定值定義了可能導致元件永久損壞的應力極限。為確保可靠性能,不建議在接近或達到這些極限的條件下操作。

光譜線半高寬 (Δλ): 約 15 nm (典型值)。這表示光譜純度;15nm 的數值是基於 AlInGaP 的黃綠光 LED 之特徵。

順向電壓 (VF): 2.0V (典型值),在 20mA 時最大值為 2.4V。這是在指定電流下操作時 LED 兩端的電壓降。對於設計限流電路至關重要。

逆向電流 (IR): 在逆向電壓 (VR) 5V 下,最大值為 10 μA。此參數僅供測試用途;元件並非設計用於逆向偏壓下操作。

3. 分級系統說明 為確保量產的一致性,LED 會根據性能進行分級。這讓設計師能選擇符合其應用特定最低標準的元件。

分級 R2: 140.0 – 180.0 mcd

每個亮度分級的公差為 ±11%。

料袋間距: 在載帶尺寸中定義。

每捲盤元件數量: 2000 個。

缺件: 根據規格,最多允許連續兩個空料袋。

包裝符合 ANSI/EIA-481 元件包裝標準。

注意: 確切的溫度曲線必須針對特定的 PCB 組裝件進行特性分析,需考慮電路板厚度、元件密度及使用的錫膏。

6.2 手工焊接 若必須進行手工焊接,必須極度小心:

烙鐵溫度: 最高 300°C。

8. 應用備註與設計考量

8.1 限流設計 務必使用串聯電阻或恆流驅動器將順向電流設定為所需值 (例如:20mA)。電阻值可使用歐姆定律計算:R = (電源電壓 - LED_Vf) / 期望電流。為進行保守設計,應使用規格書中的最大 Vf (2.4V),以確保即使使用低 Vf 的 LED,電流也不會超過限制。

8.2 熱管理 雖然功耗較低 (72mW),但在 PCB 上進行有效的熱管理有助於維持性能和壽命,特別是在高環境溫度環境下或以較高電流驅動時。確保 LED 焊墊與 PCB 銅箔之間有良好的熱連接,有助於散熱。

Tolerance for each wavelength bin is ±1 nm.

. Performance Curve Analysis

While specific graphs are referenced in the datasheet, their implications are critical for design.

.1 Current vs. Voltage (I-V) Characteristic

The I-V curve for an LED is exponential. The typical forward voltage (2.0V) is specified at 20mA. Designers must use a current-limiting resistor or constant-current driver to ensure the operating point remains stable, as a small change in voltage can cause a large change in current, potentially exceeding maximum ratings.

.2 Luminous Intensity vs. Forward Current

Luminous intensity is approximately proportional to forward current within the operating range. Operating above the recommended DC current (20mA) may increase brightness but will also increase junction temperature, potentially reducing lifespan and causing color shift.

.3 Temperature Dependence

LED performance is temperature-sensitive. Typically, forward voltage decreases with increasing temperature, while luminous intensity also decreases. Operating at the upper limit of the temperature range (85°C) will result in lower light output compared to operation at 25°C.

. Mechanical and Packaging Information

.1 Device Dimensions and Polarity

The LED package has specific physical dimensions critical for PCB footprint design. The datasheet includes a detailed dimensional drawing. Polarity is indicated by a cathode mark (typically a notch, green dot, or other marking on the package). Correct orientation is essential for circuit operation.

.2 Recommended PCB Pad Design

A land pattern (footprint) is provided for the PCB. Adhering to this recommended pad layout is crucial for achieving reliable solder joints during reflow soldering, ensuring proper mechanical attachment and thermal dissipation.

.3 Tape and Reel Packaging Specifications

The device is supplied in embossed carrier tape with a protective cover tape, wound onto 7-inch (178mm) diameter reels. Key specifications include:

. Soldering and Assembly Guidelines

.1 IR Reflow Soldering Profile (Pb-Free)

A suggested temperature profile compliant with J-STD-020B is provided for lead-free solder processes. Key parameters include:

Note:The exact profile must be characterized for the specific PCB assembly, considering board thickness, component density, and solder paste used.

.2 Hand Soldering

If hand soldering is necessary, extreme care must be taken:

.3 Cleaning

If post-solder cleaning is required, only specified solvents should be used to avoid damaging the LED's plastic lens and package. Recommended agents include ethyl alcohol or isopropyl alcohol. The LED should be immersed at normal temperature for less than one minute.

. Storage and Handling Cautions

.1 Moisture Sensitivity

The LED package is moisture-sensitive. Prolonged exposure to ambient humidity can lead to popcorn cracking during reflow soldering.

.2 Drive Method

LEDs are current-operated devices. To ensure uniform brightness when connecting multiple LEDs, they should be driven with a constant current source. Connecting LEDs directly in parallel with a single voltage source and resistor is not recommended due to variations in forward voltage (Vf) between individual devices, which can lead to significant differences in current and, consequently, brightness. A series connection with an appropriate current-limiting resistor or the use of individual resistors for each parallel LED is preferred.

. Application Notes and Design Considerations

.1 Current Limiting

Always use a series resistor or constant-current driver to set the forward current to the desired value (e.g., 20mA). The resistor value can be calculated using Ohm's Law: R = (Vsupply - Vf_LED) / I_desired. Use the maximum Vf from the datasheet (2.4V) for a conservative design to ensure the current does not exceed limits even with a low-Vf LED.

.2 Thermal Management

While the power dissipation is low (72mW), effective thermal management on the PCB can help maintain performance and longevity, especially in high ambient temperature environments or when driving at higher currents. Ensuring a good thermal connection from the LED pads to the PCB copper can help dissipate heat.

.3 Optical Design

The 120-degree viewing angle and diffused lens provide a wide, soft light emission. This makes the LED suitable for applications requiring even illumination over an area or where the indicator needs to be visible from a wide range of angles, without the need for secondary optics like light pipes in many cases.

. Frequently Asked Questions (Based on Technical Parameters)

.1 What is the difference between Peak Wavelength and Dominant Wavelength?

Peak Wavelength (λP) is the physical wavelength at the highest intensity point in the LED's emission spectrum. Dominant Wavelength (λd) is a calculated value based on human color perception (CIE coordinates) that represents the single wavelength of the perceived color. For design purposes, especially regarding color matching, the Dominant Wavelength and its binning are more relevant.

.2 Can I drive this LED at 30mA continuously?

While the Absolute Maximum Rating for DC Forward Current is 30mA, the Electro-Optical Characteristics are specified at 20mA. Operating at 30mA continuously will generate more heat, potentially reducing luminous efficiency and lifespan. For reliable long-term operation, it is advisable to design for a current at or below the typical test condition of 20mA.

.3 How do I interpret the binning codes when ordering?

You must specify the desired bin codes for Vf, Iv, and Wd based on your application's requirements for voltage consistency, brightness level, and color point. For example, an order might specify bins D3 (Vf), R1 (Iv), and D (Wd) to get parts with medium voltage, high brightness, and a specific yellow-green hue.

. Operational Principles and Technology Context

.1 AlInGaP Semiconductor Technology

This LED uses an Aluminum Indium Gallium Phosphide (AlInGaP) semiconductor material. This material system is highly efficient for producing light in the amber, yellow, and green regions of the visible spectrum. Compared to older technologies, AlInGaP LEDs offer higher brightness, better efficiency, and improved temperature stability.

.2 Diffused Lens Function

The diffused (non-clear) lens contains scattering particles that mix the light emitted from the small semiconductor chip. This process broadens the viewing angle (to 120 degrees) and creates a more uniform, softer appearance by eliminating the bright "hot spot" typically seen in LEDs with clear lenses. This is ideal for applications where the LED is viewed directly.

LED規格術語詳解

LED技術術語完整解釋

一、光電性能核心指標

術語 單位/表示 通俗解釋 為什麼重要
光效(Luminous Efficacy) lm/W(流明/瓦) 每瓦電能發出的光通量,越高越節能。 直接決定燈具的能效等級與電費成本。
光通量(Luminous Flux) lm(流明) 光源發出的總光量,俗稱"亮度"。 決定燈具夠不夠亮。
發光角度(Viewing Angle) °(度),如120° 光強降至一半時的角度,決定光束寬窄。 影響光照範圍與均勻度。
色溫(CCT) K(開爾文),如2700K/6500K 光的顏色冷暖,低值偏黃/暖,高值偏白/冷。 決定照明氛圍與適用場景。
顯色指數(CRI / Ra) 無單位,0–100 光源還原物體真實顏色的能力,Ra≥80為佳。 影響色彩真實性,用於商場、美術館等高要求場所。
色容差(SDCM) 麥克亞當橢圓步數,如"5-step" 顏色一致性的量化指標,步數越小顏色越一致。 保證同一批燈具顏色無差異。
主波長(Dominant Wavelength) nm(奈米),如620nm(紅) 彩色LED顏色對應的波長值。 決定紅、黃、綠等單色LED的色相。
光譜分佈(Spectral Distribution) 波長 vs. 強度曲線 顯示LED發出的光在各波長的強度分佈。 影響顯色性與顏色品質。

二、電氣參數

術語 符號 通俗解釋 設計注意事項
順向電壓(Forward Voltage) Vf LED點亮所需的最小電壓,類似"啟動門檻"。 驅動電源電壓需≥Vf,多個LED串聯時電壓累加。
順向電流(Forward Current) If 使LED正常發光的電流值。 常採用恆流驅動,電流決定亮度與壽命。
最大脈衝電流(Pulse Current) Ifp 短時間內可承受的峰值電流,用於調光或閃光。 脈衝寬度與佔空比需嚴格控制,否則過熱損壞。
反向電壓(Reverse Voltage) Vr LED能承受的最大反向電壓,超過則可能擊穿。 電路中需防止反接或電壓衝擊。
熱阻(Thermal Resistance) Rth(°C/W) 熱量從晶片傳到焊點的阻力,值越低散熱越好。 高熱阻需更強散熱設計,否則結溫升高。
靜電放電耐受(ESD Immunity) V(HBM),如1000V 抗靜電打擊能力,值越高越不易被靜電損壞。 生產中需做好防靜電措施,尤其高靈敏度LED。

三、熱管理與可靠性

術語 關鍵指標 通俗解釋 影響
結溫(Junction Temperature) Tj(°C) LED晶片內部的實際工作溫度。 每降低10°C,壽命可能延長一倍;過高導致光衰、色漂移。
光衰(Lumen Depreciation) L70 / L80(小時) 亮度降至初始值70%或80%所需時間。 直接定義LED的"使用壽命"。
流明維持率(Lumen Maintenance) %(如70%) 使用一段時間後剩餘亮度的百分比。 表徵長期使用後的亮度保持能力。
色漂移(Color Shift) Δu′v′ 或 麥克亞當橢圓 使用過程中顏色的變化程度。 影響照明場景的顏色一致性。
熱老化(Thermal Aging) 材料性能下降 因長期高溫導致的封裝材料劣化。 可能導致亮度下降、顏色變化或開路失效。

四、封裝與材料

術語 常見類型 通俗解釋 特點與應用
封裝類型 EMC、PPA、陶瓷 保護晶片並提供光學、熱學介面的外殼材料。 EMC耐熱好、成本低;陶瓷散熱優、壽命長。
晶片結構 正裝、倒裝(Flip Chip) 晶片電極佈置方式。 倒裝散熱更好、光效更高,適用於高功率。
螢光粉塗層 YAG、矽酸鹽、氮化物 覆蓋在藍光晶片上,部分轉化為黃/紅光,混合成白光。 不同螢光粉影響光效、色溫與顯色性。
透鏡/光學設計 平面、微透鏡、全反射 封裝表面的光學結構,控制光線分佈。 決定發光角度與配光曲線。

五、質量控制與分檔

術語 分檔內容 通俗解釋 目的
光通量分檔 代碼如 2G、2H 按亮度高低分組,每組有最小/最大流明值。 確保同一批產品亮度一致。
電壓分檔 代碼如 6W、6X 按順向電壓範圍分組。 便於驅動電源匹配,提高系統效率。
色區分檔 5-step MacAdam橢圓 按顏色坐標分組,確保顏色落在極小範圍內。 保證顏色一致性,避免同一燈具內顏色不均。
色溫分檔 2700K、3000K等 按色溫分組,每組有對應的坐標範圍。 滿足不同場景的色溫需求。

六、測試與認證

術語 標準/測試 通俗解釋 意義
LM-80 流明維持測試 在恆溫條件下長期點亮,記錄亮度衰減數據。 用於推算LED壽命(結合TM-21)。
TM-21 壽命推演標準 基於LM-80數據推算實際使用條件下的壽命。 提供科學的壽命預測。
IESNA標準 照明工程學會標準 涵蓋光學、電氣、熱學測試方法。 行業公認的測試依據。
RoHS / REACH 環保認證 確保產品不含有害物質(如鉛、汞)。 進入國際市場的准入條件。
ENERGY STAR / DLC 能效認證 針對照明產品的能效與性能認證。 常用於政府採購、補貼項目,提升市場競爭力。