LED Indication - Discrete

Part Number	Description / PDF	Quantity
LTST-C193KRKT-2A Lite-On, Inc.	LED RED CLEAR CHIP SMD	0
LTL-4231N-1 Lite-On, Inc.	LED GREEN DIFFUSED T-1 T/H	94
LTST-C155GEKT Lite-On, Inc.	LED GREEN/RED CLEAR CHIP SMD	5516
LTL-293SJW Lite-On, Inc.	LED GREEN/RED DIFFUSED T/H	2959
LTL2H3KEK Lite-On, Inc.	LED RED CLEAR T-1 3/4 T/H	11504
LTST-C191TGKT Lite-On, Inc.	LED GREEN CLEAR CHIP SMD	118795
LTST-C191KSKT Lite-On, Inc.	LED YELLOW CLEAR SMD	0
LTST-C190KSKT Lite-On, Inc.	LED YELLOW CLEAR CHIP SMD	0
LTL-307E Lite-On, Inc.	LED RED DIFFUSED T-1 3/4 T/H	0
LTST-S321KRKT Lite-On, Inc.	LED RED CLEAR 1208 SMD R/A	0
LTST-C190CKT Lite-On, Inc.	LED RED CLEAR CHIP SMD	0
LTST-S270YKT Lite-On, Inc.	LED YELLOW CLEAR SMD R/A	160
LTW-42NC5 Lite-On, Inc.	LED WHITE CLEAR T-1 T/H	15087
LTL2R3KG Lite-On, Inc.	LED GREEN DIFFUSED T-1 3/4 T/H	6702
LTST-020KGKT Lite-On, Inc.	LED GREEN CLEAR SMD R/A	2853
LTST-T680TBWT Lite-On, Inc.	LED BLUE DIFFUSED 2SMD	117870
LTST-T680KSWT Lite-On, Inc.	LED YELLOW DIFFUSED 2SMD	2205
LTST-T680KGWT Lite-On, Inc.	LED GREEN DIFFUSED 2SMD	5660
LTW-2S3D7 Lite-On, Inc.	LED WHITE CLEAR T-1 3/4 T/H	3688
LTST-S270EKT Lite-On, Inc.	LED RED CLEAR SMD R/A	20000

LED Indication - Discrete

1. Overview

Discrete Light Emitting Diodes (LEDs) are single-chip optoelectronic devices that convert electrical energy into light through electroluminescence. This product category forms the foundation of modern indication systems, offering advantages including low power consumption, long lifespan, and high reliability. Their importance spans across consumer electronics, industrial equipment, automotive systems, and communication infrastructure.

2. Major Types and Functional Classification

Type	Functional Characteristics	Application Examples
Visible LEDs	Emits light in visible spectrum (400-700nm), available in multiple colors	Indicator lamps, display backlighting, decorative lighting
Infrared LEDs	Emits 700nm-1mm wavelength radiation, invisible to human eye	Remote controls, security sensors, night vision systems
High-Brightness LEDs	Enhanced luminous intensity (>1000mcd) with advanced packaging	Automotive lighting, outdoor displays, emergency signage
UV LEDs	Ultraviolet spectrum emission (280-400nm)	Sterilization equipment, counterfeit detection, curing systems

3. Structure and Composition

Typical discrete LED construction includes:

Die: Semiconductor chip (GaN/InGaN for blue/green, AlGaInP for red)
Encapsulation: Epoxy or silicone lens for light extraction and protection
Lead Frame: Copper or iron alloy for electrical connection and heat dissipation
Phosphor Coating: Used in white LEDs for wavelength conversion
Reflective Cup: Optimizes light directionality

4. Key Technical Parameters

Parameter	Significance	Typical Range
Wavelength	Determines light color and application suitability	375nm-940nm
Luminous Intensity	Measures brightness output (mcd)	50-10,000mcd
Forward Current	Operating current rating	20-150mA
Forward Voltage	Electrical potential drop	1.8-3.6V
Viewing Angle	Light emission spread measurement	5 -120

5. Application Fields

Primary application sectors include:

Consumer Electronics: Mobile phone indicators, keyboard backlighting
Automotive: Dashboard indicators, brake light systems
Industrial: Machine status indicators, safety signage
Medical: Diagnostic equipment indicators, phototherapy devices
Telecommunications: Network equipment status lights

6. Leading Manufacturers and Products

Manufacturer	Product Series	Key Features
Cree Inc.	XLamp XP-G3	High brightness (3200mcd), 120 viewing angle
OSRAM Opto	OSTAR Projection	High-power LED for automotive lighting
Nichia Corp.	NSHU5991	UV LED (365nm) for curing applications
Everlight Electronics	LTST-C19HE8WT	Tri-color LED for RGB indication

7. Selection Recommendations

Key consideration factors:

Spectral Requirements: Match wavelength to application needs
Environmental Conditions: Temperature range (-40 C to +85 C typical)
Power Constraints: Select appropriate current/voltage ratings
Optical Design: Consider lens type and viewing angle
Reliability: Check MTTF (Mean Time to Failure) specifications

Industry Development Trends

Current technology directions include:

Miniaturization: Development of micro-LED ( LED) with dimensions <50 m
Efficiency Improvement: Targeting >300lm/W efficacy for visible LEDs
Smart Integration: Incorporating driver ICs and sensors in LED packages
Material Innovation: GaN-on-silicon substrates for cost reduction
Regulatory Compliance: RoHS/REACH compliant packaging materials