7.62mm Reddish-Orange Seven Segment Display Datasheet - Size 19.0x13.2x8.0mm - Forward Voltage 2.0V - Power 60mW - English Technical Document

1. Product Overview

This document details the technical specifications for a 7.62mm (0.3-inch) digit height, seven-segment alphanumeric display. The device is designed for through-hole mounting (THT) and utilizes AlGaInP chip technology to emit a reddish-orange light. It features white light-emitting segments against a gray background surface, which enhances contrast and readability, particularly in bright ambient lighting conditions. The product is categorized for luminous intensity and is compliant with Pb-free and RoHS environmental standards, making it suitable for a wide range of electronic applications requiring reliable numeric or limited alphanumeric readouts.

1.1 Core Advantages and Target Market

The primary advantages of this display include its adherence to an industrial standard footprint, ensuring compatibility with existing PCB layouts and sockets designed for this common size. Its low power consumption is a key benefit for battery-operated or energy-efficient devices. The gray surface resin significantly improves contrast by reducing reflected ambient light, making the illuminated segments stand out more clearly. The device is primarily targeted at applications requiring durable, legible, and cost-effective numeric displays, such as consumer home appliances, industrial instrument panels, and various digital readout systems.

2. Technical Parameter Deep-Dive

The following sections provide a detailed, objective analysis of the device's electrical, optical, and thermal specifications as defined in the datasheet.

2.1 Absolute Maximum Ratings

These ratings define the stress limits beyond which permanent damage to the device may occur. Operation under or at these limits is not guaranteed and should be avoided in reliable design.

• Reverse Voltage (V_R): 5V. Exceeding this voltage in reverse bias can cause junction breakdown.
• Continuous Forward Current (I_F): 25mA. This is the maximum DC current recommended for continuous operation.
• Peak Forward Current (I_FP): 60mA. This is permissible only under pulsed conditions (duty cycle ≤ 10%, frequency ≤ 1kHz) and must not be used for DC bias.
• Power Dissipation (P_d): 60mW. This is the maximum power the package can dissipate at an ambient temperature (T_a) of 25°C. The power derating curve must be consulted for higher temperatures.
• Operating Temperature (T_opr): -40°C to +85°C. The device is guaranteed to function within this ambient temperature range.
• Storage Temperature (T_stg): -40°C to +100°C.
• Soldering Temperature (T_sol): 260°C for a maximum duration of 5 seconds, which is typical for wave or hand soldering processes.

2.2 Electro-Optical Characteristics

These parameters are measured at a standard ambient temperature of 25°C and define the device's performance under normal operating conditions.

• Luminous Intensity (I_v): The typical value is 17.6 mcd per segment when driven at a forward current (I_F) of 10mA. The minimum specified value is 7.8 mcd. A tolerance of ±10% applies to the luminous intensity. Designers should use the minimum value for worst-case brightness calculations.
• Peak Wavelength (λ_p): 621 nm (typical). This is the wavelength at which the spectral emission is strongest.
• Dominant Wavelength (λ_d): 615 nm (typical). This wavelength describes the perceived color of the light and is more relevant for human vision than the peak wavelength.
• Spectrum Radiation Bandwidth (Δλ): 18 nm (typical). This indicates the spectral purity; a smaller bandwidth means a more monochromatic color.
• Forward Voltage (V_F): 2.0V typical, 2.4V maximum at I_F=20mA. The tolerance is ±0.1V. This parameter is crucial for designing the current-limiting circuitry.
• Reverse Current (I_R): Maximum 100 µA at V_R=5V. This is the leakage current when the device is reverse-biased.

3. Binning System Explanation

The datasheet indicates that the devices are \"Categorized for luminous intensity.\" This implies a binning or sorting process post-manufacturing.

• Luminous Intensity Binning: The primary binning criterion is luminous intensity (I_v). Devices are tested and grouped into specific intensity ranges or \"CAT\" codes (as referenced in the packing label). This ensures consistency in brightness within a single production batch or order. Designers specifying this part should be aware that brightness may vary between different CAT codes.
• Color/Wavelength: While not explicitly mentioned as a binned parameter, the typical values for peak (621nm) and dominant wavelength (615nm) are provided. For most applications using AlGaInP for reddish-orange, the color variation is typically tight, but critical color-matching applications should verify with the supplier.
• Forward Voltage: The specified tolerance is ±0.1V, which is relatively tight. While not necessarily a formal bin, this tight tolerance simplifies driver design by reducing the variation in voltage drop across the display.

4. Performance Curve Analysis

The datasheet provides typical characteristic curves which are essential for understanding device behavior under non-standard conditions.

4.1 Spectrum Distribution

The spectral output curve shows a characteristic emission peak around 621 nm, confirming the reddish-orange color. The 18nm bandwidth indicates a reasonably saturated color. The curve shape is typical for AlGaInP materials.

4.2 Forward Current vs. Forward Voltage (I-V Curve)

This curve illustrates the non-linear relationship between current and voltage. It shows that for a given forward current (e.g., 20mA), the forward voltage will typically be around 2.0V. The curve's slope represents the dynamic resistance of the LED junction. Designers use this to calculate the necessary supply voltage and series resistor value for proper current regulation.

4.3 Forward Current Derating Curve

This is one of the most critical graphs for reliable design. It shows how the maximum permissible continuous forward current must be reduced as the ambient temperature increases above 25°C. At the maximum operating temperature of 85°C, the allowable continuous current is significantly lower than the 25mA absolute maximum rating at 25°C. Ignoring this derating can lead to accelerated lumen depreciation, color shift, and catastrophic failure due to overheating.

5. Mechanical and Package Information

5.1 Package Dimensions

The display has a standard DIP (Dual In-line Package) footprint. Key dimensions from the drawing include:

• Overall Height: 8.0 mm (max)
• Body Width: 13.2 mm (nominal)
• Body Length: 19.0 mm (nominal)
• Digit Height: 7.62 mm (0.3 inches)
• Lead (Pin) Spacing: 2.54 mm (0.1 inch) standard grid.
• Lead Diameter: 0.5 mm (typical)

Tolerances are ±0.25mm unless otherwise specified. These dimensions are vital for PCB layout, ensuring proper fit in the mounting hole and correct spacing for wave soldering.

5.2 Pinout and Polarity Identification

The internal circuit diagram shows a common-cathode configuration for the seven segments. This means all segment LEDs share a common negative connection (cathode). The individual anodes for segments a through g are on separate pins. The common cathode pin must be connected to ground (or the lower voltage potential) in the circuit. The pinout diagram must be consulted during PCB design to correctly route signals to each segment. Misconnection will result in segments not illuminating or incorrect numbers/characters being displayed.

6. Soldering and Assembly Guidelines

• Soldering: The absolute maximum soldering temperature is 260°C for up to 5 seconds. This is suitable for hand soldering with an iron or wave soldering processes. Care should be taken to avoid prolonged heat exposure to prevent damage to the plastic package and internal wire bonds.
• ESD (Electrostatic Discharge) Precautions: The LED dice are sensitive to ESD. Recommended handling precautions include using grounded wrist straps, ESD-safe workstations with conductive mats, and proper grounding of all equipment. Insulating materials should be treated with ionizers or kept at a controlled humidity to dissipate charge.
• Cleaning: While not specified, standard PCB cleaning processes compatible with epoxy resin packages can be used. Consult the manufacturer for specific chemical compatibility.
• Storage: Devices should be stored within the specified storage temperature range (-40°C to +100°C) in a low-humidity, ESD-safe environment.

7. Packaging and Ordering Information

• Packaging Format: The devices are packed in tubes, then boxes, and finally cartons. The specific packing is 26 pieces per tube, 88 tubes per box, and 4 boxes per carton, totaling 9,152 pieces per carton.
• Label Information: The packing label includes critical information for traceability and identification:
  • CPN: Customer's Part Number
  • P/N: Manufacturer's Part Number (e.g., ELS-321USOWA/S530-A4)
  • QTY: Quantity in the package
  • CAT: Luminous Intensity Rank (the bin code)
  • LOT No.: Manufacturing lot number for traceability.

8. Application Suggestions

8.1 Typical Application Circuits

Being a common-cathode display, it is typically driven by a microcontroller or dedicated display driver IC (e.g., 74HC595 shift register, MAX7219). Each segment anode is connected to the driver output through a current-limiting resistor. The value of this resistor (R_series) is calculated using Ohm's Law: R_series = (V_supply - V_F) / I_F. Using the maximum V_F (2.4V) for a robust design, and a desired I_F of 10mA with a 5V supply: R = (5V - 2.4V) / 0.01A = 260 Ω. A standard 270 Ω resistor would be appropriate. The common cathode pin(s) are switched to ground by the controller to enable the digit.

8.2 Design Considerations

• Current Limiting: Always use a series resistor or constant current driver. Connecting directly to a voltage source will destroy the LED due to excessive current.
• Multiplexing: For multi-digit displays, multiplexing is common to save I/O pins. Ensure the peak current in multiplexed designs does not exceed the I_FP rating (60mA) and that the average current over time respects the I_F derating for the duty cycle used.
• Viewing Angle: The gray background improves contrast but may slightly affect the viewing angle compared to a black background. Consider the intended viewing position of the end product.
• Heat Management: In high ambient temperature environments or when driving near maximum current, ensure adequate ventilation around the display to prevent the junction temperature from exceeding safe limits.

9. Technical Comparison and Differentiation

Compared to older technologies or smaller displays, this device offers specific advantages:

• vs. Incandescent or VFD Displays: Much lower power consumption, longer lifetime, higher shock/vibration resistance, and cooler operation.
• vs. Smaller LED Displays (e.g., 5mm or 3mm digit): The 7.62mm digit height offers superior readability at a distance, making it suitable for panel meters and appliances where the user may not be up close.
• vs. LCD Displays: LEDs are self-illuminating, providing excellent visibility in low-light conditions without a backlight. They also have a much wider operating temperature range and faster response time.
• Key Differentiator: The combination of the industrial-standard 7.62mm size, the contrast-enhancing gray surface, and the reliable AlGaInP technology for reddish-orange emission positions this display as a robust, legible, and energy-efficient choice for industrial and consumer numeric readouts.

10. Frequently Asked Questions (Based on Technical Parameters)

10.1 Can I drive this display with 20mA continuously?

Yes, but with caution. The absolute maximum continuous current is 25mA at 25°C ambient. Driving at 20mA is within spec, but you must consult the forward current derating curve if the ambient temperature is expected to rise. At 85°C, the maximum allowed continuous current is significantly lower. For reliable long-term operation, driving at 10-15mA is often a safer practice that also extends operational life.

10.2 Why is the typical forward voltage (2.0V) lower than for some white or blue LEDs?

The forward voltage is primarily determined by the semiconductor material's bandgap energy. AlGaInP, used for reddish-orange/red/amber colors, has a lower bandgap energy than the InGaN materials used for blue, green, and white LEDs. A lower bandgap requires less energy (lower voltage) for electrons to cross and emit photons.

10.3 What does \"categorized for luminous intensity\" mean for my design?

It means displays from different production batches or labeled with different \"CAT\" codes may have different brightness levels. If uniform brightness across all units in your product is critical, you should specify and procure devices from a single intensity bin (CAT code). For most applications, the variation within the specified tolerance (±10%) is acceptable.

11. Practical Design Case Study

Scenario: Designing a simple 3-digit voltmeter for a benchtop power supply, operating in an environment up to 50°C.

Design Steps:

1. Drive Current Selection: Target 10mA per segment for good brightness and longevity.
2. Current Limiting Resistor: Using a 5V microcontroller supply and the max V_F of 2.4V: R = (5V - 2.4V) / 0.01A = 260Ω. Use 270Ω (nearest standard value).
3. Multiplexing: To control 3 digits (21 segments + 3 common cathodes) with fewer pins, use multiplexing with a 1/3 duty cycle. The peak current per segment during its active time slot would be 30mA to maintain an average of 10mA (since it's only on 1/3 of the time). This 30mA peak is well below the 60mA I_FP rating.
4. Thermal Check: At 50°C ambient, the derating curve must be checked. The permissible continuous current is lower than 25mA. However, since our average current per segment is only 10mA, and the display is multiplexed (each digit is off 2/3 of the time), the junction temperature rise will be minimal, making this design thermally safe.
5. Microcontroller Interface: Use a shift register like the 74HC595 to control the segment anodes, and three GPIO pins to sink the common cathodes via transistors (e.g., 2N3904 NPN transistors).

12. Operating Principle Introduction

A seven-segment LED display is an assembly of seven individual light-emitting diodes (LEDs) arranged in a figure-eight pattern. Each LED forms one segment (labeled a through g). By selectively illuminating specific combinations of these segments, all decimal numerals (0-9) and some letters can be formed. In this common-cathode device, the cathodes (negative terminals) of all seven segment LEDs are connected internally to one or more common pins. To light a segment, a positive voltage must be applied to its individual anode pin (through a current-limiting resistor), while the common cathode pin is connected to ground, completing the circuit. The light emission itself is due to electroluminescence in the AlGaInP semiconductor chip: when forward-biased, electrons and holes recombine at the p-n junction, releasing energy in the form of photons with a wavelength corresponding to the material's bandgap (around 615-621 nm for reddish-orange).

13. Technology Trends and Context

Through-hole seven-segment displays like this one represent a mature and highly reliable technology. While surface-mount device (SMD) displays are increasingly common for automated assembly and miniaturization, through-hole displays remain popular for prototyping, educational use, repair markets, and applications where mechanical robustness and ease of hand-soldering are prioritized. The use of AlGaInP is standard for high-efficiency red, orange, and amber LEDs. Trends in the broader display market include the integration of controllers/drivers into the display module, the development of ultra-high-brightness versions for sunlight readability, and a shift towards SMD packages. However, the fundamental design and electrical interface of the standard seven-segment display have remained stable for decades, ensuring long-term availability and design familiarity.