LTS-6960HR 0.56-inch Red-Orange Seven-Segment LED Display Datasheet - Digit Height 14.22mm - Forward Voltage 2.6V - Power 75mW - English Technical Documentation

1. Product Overview

The LTS-6960HR is a single-digit, seven-segment alphanumeric LED display module. It is designed to provide clear, high-contrast numeric and limited alphanumeric character representation for a wide range of electronic equipment. The device features a 0.56-inch (14.22 mm) digit height, making it suitable for applications where medium-sized, easily readable characters are required.

1.1 Core Advantages and Target Market

This display offers several key advantages that make it suitable for consumer and industrial electronics. Its primary features include low power requirement, excellent character appearance with continuous uniform segments, high brightness, high contrast, and a wide viewing angle. The solid-state construction ensures high reliability. It is categorized for luminous intensity, allowing for brightness matching in multi-digit applications, and is offered in a lead-free package compliant with RoHS directives. The target market includes office equipment, communication devices, household appliances, instrumentation panels, and other applications requiring a reliable, medium-sized numeric display.

1.2 Device Description and Features

The LTS-6960HR utilizes red-orange LED chips. These chips are fabricated using GaAsP on a transparent GaP substrate or AlInGaP on a non-transparent GaAs substrate technology. The display has a red face and red segments, providing a classic indicator appearance. It is configured as a common anode device, which is a typical configuration for simplifying drive circuitry in multiplexed applications. A right-hand decimal point is included. Key features are its 0.56-inch digit height, uniform segment illumination, low power consumption, excellent visual characteristics, high brightness and contrast, wide viewing angle, high reliability, luminous intensity categorization, and RoHS compliance.

2. Technical Parameters Deep Objective Interpretation

2.1 Absolute Maximum Ratings

The device must not be operated beyond these limits to prevent permanent damage. The maximum power dissipation per segment is 75 mW. The peak forward current per segment is 60 mA, but this is only permissible under pulsed conditions (1/10 duty cycle, 0.1ms pulse width). The continuous forward current per segment is rated at 25 mA at 25°C, with a derating factor of 0.33 mA/°C above this temperature. The device can operate and be stored within a temperature range of -35°C to +85°C. The soldering temperature is specified as 260°C for 3 seconds at a distance of 1/16 inch (approximately 1.59 mm) below the seating plane.

2.2 Electrical and Optical Characteristics

These parameters are specified at an ambient temperature (Ta) of 25°C. The average luminous intensity (Iv) per segment ranges from a minimum of 870 µcd to a typical 2400 µcd at a forward current (IF) of 10 mA. The peak emission wavelength (λp) is typically 630 nm at IF=20mA. The spectral line half-width (Δλ) is 40 nm. The dominant wavelength (λd) is 621 nm. The forward voltage per segment (VF) ranges from 2.0V (min) to 2.6V (max) at IF=20mA. The reverse current per segment (IR) is a maximum of 100 µA at a reverse voltage (VR) of 5V. It is critically important to note that this reverse voltage condition is for test purposes only; continuous operation under reverse bias is not allowed. The luminous intensity matching ratio between segments is 2:1 maximum.

3. Binning System Explanation

The datasheet indicates that the device is \"Categorized for Luminous Intensity.\" This implies a binning system based on measured light output at a standard test current (typically 10mA as per the characteristics table). Binning ensures consistency in brightness across multiple displays used in the same product, preventing uneven illumination. While specific bin code details are not provided in this excerpt, designers are advised to specify or request devices from the same luminous intensity bin when assembling multiple displays in one application to avoid hue and brightness unevenness problems.

4. Performance Curve Analysis

The datasheet references \"Typical Electrical / Optical Characteristics Curves\" which are essential for detailed design. Although the specific graphs are not provided in the text excerpt, such curves typically include: Forward Current vs. Forward Voltage (IV Curve), which shows the nonlinear relationship and helps in selecting current-limiting resistors; Luminous Intensity vs. Forward Current, showing how light output increases with current; Luminous Intensity vs. Ambient Temperature, indicating the derating of light output as temperature rises; and possibly the Spectral Distribution curve, showing the concentration of emitted light around the peak and dominant wavelengths. These curves allow engineers to optimize drive conditions and understand performance under non-standard temperatures.

5. Mechanical and Package Information

5.1 Package Dimensions

The display comes in a standard through-hole package. All dimensions are provided in millimeters. The dimensional tolerances are ±0.25 mm (0.01 inch) unless otherwise specified on the mechanical drawing (not fully detailed in the text). The package includes ten pins for electrical connection.

5.2 Pin Connection and Polarity Identification

The internal circuit diagram shows a common anode configuration for all segments. The pinout is as follows: Pin 1: Cathode E; Pin 2: Cathode D; Pin 3: Common Anode; Pin 4: Cathode C; Pin 5: Cathode D.P. (Decimal Point); Pin 6: Cathode B; Pin 7: Cathode A; Pin 8: Common Anode; Pin 9: Cathode F; Pin 10: Cathode G. The presence of two common anode pins (3 and 8) is typical to distribute current and improve reliability. The decimal point is located on the right-hand side of the digit.

6. Soldering and Assembly Guidelines

The absolute maximum rating specifies a solder temperature of 260°C for 3 seconds when measured 1/16 inch below the seating plane. This is a critical parameter for wave or hand soldering processes to prevent thermal damage to the LED chips or the plastic package. The datasheet strongly cautions against using unsuitable tools or assembly methods that apply abnormal force to the display body, as this can cause mechanical damage.

7. Storage Conditions

For long-term storage of unused devices, specific conditions are recommended to prevent pin oxidation. For standard LED displays in original packaging, the recommended storage environment is a temperature between 5°C and 30°C with relative humidity below 60% RH. For SMD-type displays (though the LTS-6960HR is through-hole, the guideline is included), once the original sealed moisture barrier bag is opened, the devices should be used within 168 hours (MSL Level 3) under the same temperature and humidity conditions. If stored longer than 168 hours after opening, baking at 60°C for 24 hours before soldering is recommended. It is generally advised to consume displays as soon as possible and avoid large long-term inventories.

8. Application Suggestions

8.1 Typical Application Scenarios

This display is intended for ordinary electronic equipment including office automation devices, communication equipment, household appliances, and instrumentation. It is suitable for applications like digital clocks, panel meters, scoreboards, appliance control panels, and industrial control readouts where a single numeric digit is required.

8.2 Design Considerations and Cautions

Drive Circuit Design: Constant current driving is recommended over constant voltage to ensure consistent luminous intensity and longevity. The circuit must be designed to accommodate the full range of forward voltage (VF: 2.0V to 2.6V) to guarantee the intended drive current is always delivered. The safe operating current must be selected considering the maximum ambient temperature of the application, factoring in the current derating of 0.33 mA/°C above 25°C.
Protection: The driving circuit should incorporate protection against reverse voltages and transient voltage spikes during power-up or shutdown, as reverse bias can cause metal migration and failure. Rapid changes in ambient temperature, especially in humid environments, should be avoided to prevent condensation on the display.
Optical Interface: If a filter or overlay is used, it should not be in direct, tight contact with the display surface, as pressure-sensitive adhesives on films may shift.
Reliability Note: The device is not recommended for safety-critical applications (aviation, medical life-support, etc.) without prior consultation, as its failure could jeopardize life or health.

9. Technical Comparison and Differentiation

Compared to smaller digit displays (e.g., 0.3-inch), the LTS-6960HR offers superior visibility at a distance or in well-lit conditions due to its 0.56-inch height. Compared to simple discrete LEDs, it provides a formed character in a single package, simplifying PCB layout and assembly. Its common anode configuration is advantageous when interfacing with microcontroller ports configured as current sinks. The use of AlInGaP/GaAsP technology provides a classic red-orange color with good efficiency. The explicit categorization for luminous intensity is a key differentiator for applications requiring uniform appearance across multiple units.

10. Frequently Asked Questions Based on Technical Parameters

Q: What is the purpose of the two common anode pins (3 and 8)?
A: They are internally connected. Using both pins helps distribute the total anode current, reduces current density in the PCB traces and the package leads, and can improve reliability. In a design, they should be connected together on the PCB.
Q: Can I drive this display with a 5V supply and a resistor?
A: Yes, but you must calculate the current-limiting resistor based on the worst-case forward voltage. Using the maximum VF (2.6V) at a desired IF (e.g., 10mA), the resistor value R = (5V - 2.6V) / 0.01A = 240 Ohms. Always verify the actual current does not exceed the maximum continuous rating.
Q: What does \"1/10 Duty Cycle, 0.1ms Pulse Width\" mean for the peak current?
A: You can briefly pulse the segment with up to 60mA, but the pulse must be no wider than 0.1 milliseconds, and the average current over time must not exceed the continuous rating. For example, a 0.1ms pulse every 1ms (10% duty cycle) gives an average of 6mA if the peak is 60mA.
Q: Why is reverse voltage testing mentioned if it's not allowed in operation?
A: The reverse current (IR) test at 5V is a quality and leakage test performed during manufacturing. It verifies the integrity of the LED junction. Applying reverse bias continuously in an application can degrade the device.

11. Practical Design and Usage Case

Case: Designing a Single-Digit Voltmeter Readout. A microcontroller's ADC reads a voltage and needs to display it on one digit (0-9). The microcontroller port pins can sink 20mA. The design uses a common anode display, so the microcontroller pins connect to the segment cathodes (through small series resistors for extra protection). The common anode pins are connected together and driven by a PNP transistor (or a PMOS FET) switched by another microcontroller pin. The firmware multiplexes the digit by turning on the transistor and sinking current through the appropriate cathode pins to illuminate the desired segments for the number. The current for each segment is set by the microcontroller's sink capability and the resistor, ensuring it stays below 25mA. The decimal point can be used for range indication.

12. Principle Introduction

A seven-segment display is an assembly of seven LED bars (segments a through g) arranged in a figure-eight pattern. By illuminating specific combinations of these segments, all decimal digits (0-9) and some letters can be formed. In a common anode configuration, all the anodes of the LEDs are connected together to a common positive voltage supply. Each segment is turned ON by applying a low voltage (ground or logic low) to its respective cathode pin, allowing current to flow through that specific LED. This configuration is often preferred when the driving logic (like a microcontroller) is better at sinking current (pulling to ground) than sourcing it.

13. Development Trends

While traditional through-hole seven-segment displays like the LTS-6960HR remain vital for many applications, trends are moving towards surface-mount device (SMD) packages for automated assembly, higher density multi-digit modules with integrated drivers (I2C or SPI interface), and displays with wider color gamuts or RGB capabilities. There is also a trend towards higher efficiency materials, like improved AlInGaP, to achieve greater brightness at lower currents. However, the fundamental simplicity, reliability, and cost-effectiveness of discrete seven-segment displays ensure their continued use in a vast array of consumer and industrial products where basic numeric output is required.