LTS-6760JD LED Display Datasheet - 0.56-inch Digit Height - Hyper Red - 2.6V Forward Voltage - English Technical Document

1. Product Overview

The LTS-6760JD is a single-digit, seven-segment alphanumeric display designed for applications requiring clear, bright numeric readouts. Its primary function is to visually represent the digits 0-9 and some letters using individually addressable LED segments. The device utilizes advanced Aluminium Indium Gallium Phosphide (AlInGaP) semiconductor technology for its light-emitting elements, specifically in a Hyper Red color. This material system is grown on a non-transparent Gallium Arsenide (GaAs) substrate, which contributes to its optical performance. The display features a gray faceplate with white segments, a combination chosen to enhance contrast and readability under various lighting conditions. It is categorized by luminous intensity, allowing for selection based on brightness requirements.

1.1 Core Advantages and Target Market

The LTS-6760JD offers several key advantages that make it suitable for a range of electronic products. Its low power requirement is a significant benefit for battery-operated or energy-efficient devices. The display provides excellent character appearance due to its continuous, uniform segments, which create a cohesive and professional-looking numeral. High brightness and high contrast ensure the display is easily legible even in brightly lit environments. A wide viewing angle allows the readout to be seen clearly from various positions, which is crucial for instrumentation and consumer electronics. The solid-state reliability of LEDs, with no moving parts and long operational life, makes it ideal for applications where durability and maintenance-free operation are priorities. Typical target markets include test and measurement equipment, industrial control panels, medical devices, automotive dashboards (for auxiliary displays), consumer appliances, and any embedded system requiring a simple, reliable numeric indicator.

2. Technical Parameter Deep-Dive

This section provides a detailed, objective analysis of the key electrical and optical parameters specified in the datasheet, explaining their significance for design engineers.

2.1 Photometric and Optical Characteristics

The optical performance is central to the display's function. The Average Luminous Intensity (Iv) is specified with a minimum of 340 \u00b5cd, a typical value of 700 \u00b5cd, and no stated maximum, measured at a forward current (I_F) of 1mA. This parameter, measured in microcandelas, quantifies the perceived brightness of the light emitted by a segment as seen by the human eye (using a CIE-matched filter). The 1mA test condition indicates suitability for low-current designs. The Peak Emission Wavelength (\u03bb_p) is 650 nm, which falls within the deep red portion of the visible spectrum, defining the \"Hyper Red\" color. The Dominant Wavelength (\u03bb_d) is 639 nm, which is the single wavelength perceived by the human eye to match the color of the light. The Spectral Line Half-Width (\u0394\u03bb) is 20 nm, indicating the spectral purity or the spread of wavelengths emitted around the peak; a narrower width would indicate a more monochromatic light. The Luminous Intensity Matching Ratio (I_V-m) of 2:1 is critical for uniform appearance; it means the dimmest segment will be no less than half as bright as the brightest segment under the same drive conditions, ensuring consistent illumination across the digit.

2.2 Electrical Parameters

The electrical specifications define the operating limits and conditions for the device. The Forward Voltage per Segment (V_F) has a typical value of 2.6V at I_F=20mA, with a maximum of 2.6V. This is the voltage drop across an LED segment when it is conducting current. Designers must ensure the driving circuit can provide this voltage. The Reverse Current per Segment (I_R) has a maximum of 100 \u00b5A at a Reverse Voltage (V_R) of 5V. This is the small leakage current that flows when the LED is reverse-biased; exceeding the 5V reverse voltage can cause damage. The Continuous Forward Current per Segment is rated at 25 mA at 25\u00b0C, with a derating factor of 0.33 mA/\u00b0C. This means the maximum safe continuous current decreases as ambient temperature rises above 25\u00b0C. For example, at 85\u00b0C, the maximum current would be approximately 25 mA - (0.33 mA/\u00b0C * (85-25)\u00b0C) = 5.2 mA. The Peak Forward Current is 90 mA but only under very specific conditions: a 1/10 duty cycle and a 0.1ms pulse width. This allows for brief over-driving to achieve higher instantaneous brightness, commonly used in multiplexed display circuits.

3. Thermal Characteristics and Absolute Maximum Ratings

These ratings define the stress limits beyond which permanent damage may occur. The Power Dissipation per Segment is 70 mW. At the typical V_F of 2.6V and I_F of 20mA, power dissipation is 52 mW (2.6V * 0.02A), which is within the limit. The Operating and Storage Temperature Range is from -35\u00b0C to +85\u00b0C. This wide range makes the device suitable for harsh environments. The Solder Temperature specification is crucial for assembly: the device can withstand a maximum temperature of 260\u00b0C for a maximum of 3 seconds, measured 1.6mm (1/16 inch) below the seating plane. This guides reflow soldering profile settings.

4. Binning System Explanation

The datasheet indicates the device is \"Categorized for Luminous Intensity.\" This implies a binning system is in place, although specific bin codes are not listed here. In manufacturing, LEDs are tested and sorted (\"binned\") based on key parameters like luminous intensity and forward voltage. This ensures consistency within a production batch. For the LTS-6760JD, the primary binning criterion is likely the Average Luminous Intensity (I_V). Devices would be grouped into bins with tight I_V ranges (e.g., 500-600 \u00b5cd, 600-700 \u00b5cd). There may also be a secondary binning for Forward Voltage (V_F) to ensure uniform brightness when driven by a constant voltage source. Designers should consult the manufacturer for specific bin availability to guarantee the required brightness uniformity across multiple displays in a product.

5. Performance Curve Analysis

While the datasheet references \"Typical Electrical / Optical Characteristic Curves,\" the specific graphs are not provided in the excerpt. Typically, such curves for an LED display would include: I-V (Current-Voltage) Curve: This shows the relationship between forward voltage and forward current for a segment. It is non-linear, with a sharp increase in current once the forward voltage exceeds a threshold (around 2.1V for this device). Luminous Intensity vs. Forward Current (I_V vs. I_F): This curve shows how brightness increases with drive current. It is generally linear at lower currents but may saturate at higher currents due to thermal effects. Luminous Intensity vs. Ambient Temperature: This shows how brightness decreases as the junction temperature of the LED increases. For AlInGaP LEDs, luminous output typically decreases with rising temperature. Spectral Distribution: A graph plotting relative intensity against wavelength, showing the peak at 650nm and the 20nm half-width. Understanding these curves allows designers to optimize drive current for desired brightness and predict performance under different thermal conditions.

6. Mechanical and Package Information

The LTS-6760JD is a through-hole display with 10 pins on a 0.1-inch (2.54 mm) pitch, a standard for such components. The package dimensions are provided in a drawing (not fully detailed in text). Key features include a digit height of 0.56 inches (14.22 mm). The overall package dimensions would determine the cutout required in the front panel. The gray face and white segments are part of the package molding. The pin length and seating plane are designed for standard through-hole PCB mounting. Polarity is clearly indicated by the pin connection diagram and the internal circuit, which shows a common anode configuration.

6.1 Pin Connection and Internal Circuit

The device has a Common Anode configuration. This means the anodes (positive terminals) of all LED segments are connected internally and brought out to two pins (Pin 3 and Pin 8), which are tied together. Each segment's cathode (negative terminal) is brought out to an individual pin (Pins 1, 2, 4, 5, 6, 7, 9, 10 corresponding to segments E, D, C, DP, B, A, F, G). To illuminate a segment, the common anode pin(s) must be connected to a voltage source higher than the segment's V_F, and the corresponding cathode pin must be connected to a lower voltage (typically ground) through a current-limiting resistor. The right-hand decimal point (DP) is included as a separate segment. This configuration is common and simplifies driving with microcontroller I/O ports configured as current sinks.

7. Soldering and Assembly Guidelines

For through-hole components, wave soldering is the typical process. The critical parameter provided is the maximum solder temperature: 260\u00b0C for a maximum of 3 seconds, measured 1.6mm below the seating plane. This must be adhered to during wave soldering to prevent damage to the LED chips or the plastic package. Preheating is recommended to minimize thermal shock. For manual soldering, a temperature-controlled iron should be used, and contact time with each pin should be minimized. After soldering, the display should be cleaned according to standard PCB cleaning procedures, ensuring no flux residue remains on the optical surface. During handling, care should be taken to avoid mechanical stress on the pins and the display face.

8. Packaging and Ordering Information

The base part number is LTS-6760JD. In a full datasheet, additional suffixes might denote specific bins for luminous intensity or other variations. The device is likely supplied in anti-static tubes or trays to protect the pins and prevent electrostatic discharge damage during shipping and handling. Standard quantities per tube/tray would be specified by the manufacturer. The label on the packaging should include the full part number, quantity, date code, and possibly bin code information.

9. Application Suggestions

9.1 Typical Application Circuits

The most straightforward drive method uses a microcontroller. The common anode pin(s) are connected to the positive supply rail (e.g., +5V). Each cathode pin is connected to a separate I/O pin of the microcontroller via a current-limiting resistor. The resistor value is calculated as R = (V_supply - V_F) / I_F. For a 5V supply, V_F=2.6V, and I_F=10mA: R = (5 - 2.6) / 0.01 = 240 Ohms. The microcontroller sinks current to ground to turn a segment on. For multiplexing multiple digits, a transistor or dedicated driver IC can be used to switch the common anode of each digit sequentially at a high frequency, while the cathode patterns are updated synchronously.

9.2 Design Considerations

• Current Limiting: Always use a series resistor for each segment or a constant-current driver. Never connect an LED directly to a voltage source.
• Heat Dissipation: While power dissipation is low, ensure adequate spacing and possibly ventilation if operating at high ambient temperatures or near the maximum current.
• Viewing Angle: Position the display in the product enclosure so the wide viewing angle is oriented towards the expected user line-of-sight.
• ESD Protection: Although not explicitly stated as sensitive, handling with standard ESD precautions is recommended during assembly.
• Optical Interface: The gray/white finish provides good contrast. Ensure the protective window or overlay material does not introduce glare or color shift.

10. Technical Comparison

Compared to older technologies like incandescent or vacuum fluorescent displays (VFDs), the LTS-6760JD offers significantly lower power consumption, longer lifetime, and higher shock/vibration resistance due to its solid-state nature. Compared to other LED technologies: vs. Standard GaAsP or GaP Red LEDs: The AlInGaP Hyper Red offers higher brightness and efficiency, and a more saturated, deeper red color. vs. High-Efficiency Red (HER) LEDs: Similar technology, but the \"Hyper Red\" designation often indicates a specific, longer wavelength for optimal brightness perception. vs. Contemporary Options: Modern surface-mount (SMD) seven-segment displays offer smaller size and easier automated assembly, but through-hole displays like the LTS-6760JD remain relevant for prototyping, repair, and applications requiring robust mechanical mounting.

11. Frequently Asked Questions (Based on Technical Parameters)

Q: Can I drive this display with a 3.3V microcontroller system?

A: Yes. With a V_F of 2.6V, a 3.3V supply is sufficient. The current-limiting resistor value would be smaller: e.g., for 10mA, R = (3.3 - 2.6) / 0.01 = 70 Ohms.

Q: Why are there two common anode pins (3 and 8)?

A> This is a common design practice to improve current distribution and reliability. Internally, they are connected. You should connect both to the positive supply for best performance.

Q: What is the difference between peak wavelength and dominant wavelength?

A: Peak wavelength is the single wavelength where the emission spectrum is strongest. Dominant wavelength is the single wavelength of monochromatic light that would appear to have the same color to the human eye. They are often close but not identical, especially if the spectrum is not perfectly symmetric.

Q: How do I achieve uniform brightness if the segments have different V_F?

A: The luminous intensity matching ratio (2:1) accounts for this variation. Using a constant current drive (instead of a constant voltage with a resistor) is the best way to ensure uniform brightness, as it automatically compensates for small V_F differences.

12. Practical Use Case

Case: Designing a Simple Digital Voltmeter Readout. A designer is building a benchtop power supply unit that needs a 3-digit voltage display. They choose three LTS-6760JD displays. The microcontroller (e.g., an ATmega328) is programmed to read an analog voltage via its ADC, convert it to a decimal number, and drive the displays. To save I/O pins, they use a multiplexing technique: the common anodes of the three digits are connected to three separate microcontroller pins via NPN transistors. The eight segment cathodes (A-G, DP) are connected to eight microcontroller pins, each with a 220-ohm resistor. The software rapidly cycles through each digit, turning on its transistor and outputting the segment pattern for that digit's value. The persistence of vision makes all three digits appear continuously lit. The high brightness and contrast of the display ensure readability in a well-lit lab environment.

13. Operating Principle

The LTS-6760JD is based on the principle of electroluminescence in a semiconductor p-n junction. The active region uses an AlInGaP multi-quantum well structure. When a forward voltage exceeding the junction's built-in potential is applied, electrons from the n-type region and holes from the p-type region are injected into the active region. There, they recombine, releasing energy in the form of photons. The specific composition of the AlInGaP alloy determines the bandgap energy, which directly corresponds to the wavelength (color) of the emitted light--in this case, approximately 650 nm (red). The non-transparent GaAs substrate absorbs any downward-emitted light, improving contrast by preventing light from escaping through the back of the chip. The light from the tiny LED chips is coupled into the plastic package, which is molded into the shape of seven segments plus a decimal point. The gray face absorbs ambient light to improve contrast, while the white segment areas diffuse and transmit the red light evenly.

14. Technology Trends

While through-hole seven-segment displays like the LTS-6760JD remain in use, the industry trend has strongly shifted towards surface-mount device (SMD) packages for most new designs, enabling smaller, thinner products and fully automated assembly. For the underlying LED technology, AlInGaP remains a dominant material for high-efficiency red, orange, and yellow LEDs. Ongoing development focuses on improving internal quantum efficiency (more photons per electron) and light extraction efficiency (getting more of those photons out of the chip). There is also a trend towards higher brightness and lower operating voltages. In display applications, integrated driver circuits and smart displays with serial interfaces (like I2C or SPI) are becoming more common, reducing the microcontroller I/O and software burden compared to direct segment driving. However, the basic seven-segment form factor and its utility for numeric readouts ensure its continued relevance across many industries.