ELT-512SURWA/S530-A3 0.56\

1. Product Overview

The ELT-512SURWA/S530-A3 is a through-hole mounted, seven-segment alphanumeric display module. It features a standard industrial footprint with a digit height of 14.22mm, equivalent to 0.56 inches. The device is constructed with brilliant red AlGaInP (Aluminum Gallium Indium Phosphide) semiconductor chips, which are encapsulated within a white diffused resin to enhance light emission and viewing angle. The external surface of the display is finished in gray, providing a neutral and professional appearance suitable for various panel designs.

This display is categorized as a low-power consumption component, making it ideal for applications where energy efficiency is a consideration. It is fully compliant with Pb-free (Lead-free) and RoHS (Restriction of Hazardous Substances) directives, ensuring its suitability for use in products marketed globally with strict environmental regulations.

The primary design goal of this display is to deliver excellent reliability and readability even in bright ambient light conditions. Its standard size and through-hole packaging make it a versatile choice for both prototyping and volume production, easily integrated into printed circuit boards (PCBs) using conventional soldering techniques.

1.1 Core Advantages and Target Market

The core advantages of the ELT-512SURWA/S530-A3 stem from its material selection and design. The use of AlGaInP technology for the LED chips provides a high-efficiency brilliant red output with good color purity. The white diffused resin helps in scattering the light evenly across each segment, reducing hotspots and ensuring uniform illumination, which is critical for user readability.

The device's target markets are broad, encompassing any application requiring a clear, reliable numeric or limited alphanumeric readout. Its robustness and standard interface make it a go-to component for engineers designing systems that need to present data simply and effectively to an end-user.

2. Technical Parameter Deep Dive

A thorough understanding of the device's specifications is crucial for proper circuit design and ensuring long-term reliability. The parameters are defined under standard test conditions at an ambient temperature (Ta) of 25°C.

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 normal use.

• Reverse Voltage (V_R): 5V. Exceeding this voltage in reverse bias can cause immediate junction breakdown.
• Continuous Forward Current (I_F): 25mA. This is the maximum DC current that can be applied continuously.
• Peak Forward Current (I_FP): 60mA. This is permissible only under pulsed conditions with a duty cycle of 10% or less and a frequency of 1kHz.
• Power Dissipation (P_d): 60mW. The maximum power the device can dissipate as heat.
• Operating & Storage Temperature: -40°C to +85°C (operating), -40°C to +100°C (storage).
• Soldering Temperature (T_sol): 260°C for a duration not exceeding 5 seconds, which is compatible with standard wave or reflow soldering processes.

2.2 Electro-Optical Characteristics

These characteristics describe the device's performance under normal operating conditions. The typical values are provided for design guidance, but designers should account for the minimum and maximum limits.

• Luminous Intensity (I_v): 7.8mcd (Min), 17.6mcd (Typ) at I_F=10mA. This is the average light output per segment. A ±10% tolerance applies to this parameter.
• Peak Wavelength (λ_p): 632nm (Typ) at I_F=20mA. This is the wavelength at which the spectral emission is strongest.
• Dominant Wavelength (λ_d): 624nm (Typ) at I_F=20mA. This is the wavelength perceived by the human eye, defining the color as \"brilliant red.\"
• Spectral Bandwidth (Δλ): 20nm (Typ) at I_F=20mA, indicating the range of wavelengths emitted.
• Forward Voltage (V_F): 2.0V (Typ), 2.4V (Max) at I_F=20mA. Designers must ensure the driving circuit can provide sufficient voltage. A ±0.1V tolerance applies.
• Reverse Current (I_R): 100µA (Max) at V_R=5V.

3. Binning System Explanation

The datasheet indicates that the luminous intensity is \"categorized.\" This refers to a binning process where manufactured displays are sorted based on their measured light output. Devices within a specific bin (or \"CAT\" as noted on the label) will have luminous intensities falling within a defined range around the typical value (e.g., 17.6mcd ±10%). This allows designers to select displays with consistent brightness for their applications, ensuring a uniform appearance across multiple units in a product. The forward voltage is also controlled to a tight tolerance (±0.1V), which simplifies current-limiting resistor calculation and ensures consistent power consumption and thermal behavior across a batch of devices.

4. Performance Curve Analysis

The datasheet provides typical curves that illustrate the relationship between key parameters. These are essential for understanding behavior under non-standard conditions.

4.1 Spectrum Distribution

The spectral distribution curve shows the relative intensity of light emitted across different wavelengths. For the ELT-512SURWA/S530-A3, this curve would be centered around 632nm (peak) with a typical bandwidth of 20nm, confirming the narrow, pure red emission characteristic of AlGaInP technology. This results in high color saturation.

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

This curve depicts the non-linear relationship between the current flowing through the LED and the voltage drop across it. Initially, very little current flows until the forward voltage reaches a threshold (around 1.8-2.0V for this device). Beyond this point, the current increases rapidly with a small increase in voltage. This is why LEDs are always driven with a current-limiting mechanism (resistor or constant-current driver) and not directly with a voltage source.

4.3 Forward Current Derating Curve

This is a critical curve for reliability. It shows how the maximum allowable continuous forward current (I_F) must be reduced as the ambient operating temperature increases. As temperature rises, the LED's internal efficiency drops and its ability to dissipate heat decreases. To prevent overheating and accelerated degradation, the driving current must be lowered accordingly. For example, while 25mA is allowed at 25°C, a significantly lower current would be the maximum safe value at an ambient temperature of 85°C.

5. Mechanical and Package Information

The device uses a standard through-hole DIP (Dual In-line Package) format. The package dimension drawing provides all critical mechanical measurements for PCB layout, including:

• Overall height, width, and depth.
• Pin spacing (pitch) and diameter.
• Segment window dimensions and placement.
• Recommended PCB pad size and spacing.

Tolerances for these dimensions are typically ±0.25mm unless otherwise specified. The internal circuit diagram shows the common-cathode or common-anode configuration of the seven segments and the decimal point (if present), which is essential for designing the correct drive circuitry. The pinout identifies which pin controls each segment (A-G and DP).

6. Soldering and Assembly Guidelines

The device is suitable for standard soldering processes. The absolute maximum rating for soldering temperature is 260°C for up to 5 seconds. This aligns with typical wave soldering or hand-soldering profiles. It is crucial to avoid excessive thermal stress by not exceeding this time/temperature combination. Preheating the board is recommended to minimize thermal shock. After soldering, the device should be cleaned according to standard PCB cleaning procedures, ensuring no flux residue remains that could affect long-term reliability.

7. Packaging and Ordering Information

The device follows a specific packing flow to protect it during shipping and handling.

• Unit Packaging: 13 pieces are packed in an anti-static tube.
• Intermediate Packaging: 63 tubes are packed into a box.
• Master Carton: 4 boxes are packed into a shipping carton, totaling 3,276 pieces per carton (13 x 63 x 4).

The label on the packaging contains key information for traceability and identification:

• CPN: Customer's Part Number (if assigned).
• P/N: Manufacturer's Part Number (ELT-512SURWA/S530-A3).
• QTY: Quantity contained in the package.
• CAT: Luminous Intensity Rank (Binning category).
• LOT No: Manufacturing Lot Number for traceability.

8. Application Suggestions

8.1 Typical Application Scenarios

As listed in the datasheet, primary applications include:

• Home Appliances: Display for timers, temperature settings, or status codes on ovens, microwaves, washing machines, and air conditioners.
• Instrument Panels: Readouts for test equipment, industrial controls, automotive aftermarket gauges, and medical devices.
• Digital Readout Displays: Any device requiring numeric output, such as clocks, counters, scales, or simple data loggers.

8.2 Design Considerations

• Current Limiting: Always use a series resistor or constant-current driver. Calculate the resistor value using R = (V_supply - V_F) / I_F. Use the maximum V_F from the datasheet to ensure sufficient current at worst-case conditions.
• Multiplexing: For multi-digit displays, a multiplexing technique is commonly used to control many segments with fewer I/O pins. Ensure the peak current in this multiplexed scheme does not exceed the I_FP rating.
• Viewing Angle: The white diffused resin provides a wide viewing angle. Consider the intended user's position relative to the display during mechanical design.
• ESD Protection (Electrostatic Discharge): The LEDs are sensitive to ESD. Implement handling procedures (grounded workstations, wrist straps) during assembly. In the end product, consider adding transient voltage suppression on input lines if they are exposed to the user or external environment.

9. Technical Comparison and Differentiation

Compared to older technologies like GaAsP (Gallium Arsenide Phosphide) red LEDs, the AlGaInP used in this display offers significantly higher luminous efficiency, resulting in brighter output for the same drive current. The \"brilliant red\" color is also more saturated and visually distinct compared to standard red. The through-hole package provides superior mechanical strength and thermal conduction to the PCB compared to surface-mount devices (SMDs) in high-vibration or high-reliability applications, though it requires manual or wave soldering and takes up more board space.

10. Frequently Asked Questions (Based on Technical Parameters)

Q: Can I drive this display directly from a 5V microcontroller pin?
A: No. The typical forward voltage is 2.0V. Connecting it directly to 5V would cause excessive current to flow, destroying the LED. You must use a current-limiting resistor in series. For example, with a 5V supply, a target I_F of 10mA, and using max V_F=2.4V for safety: R = (5V - 2.4V) / 0.01A = 260Ω. A 270Ω standard resistor would be appropriate.

Q: What does \"common cathode\" or \"common anode\" mean for this display?
A: The internal circuit diagram specifies the configuration. In a common-cathode display, all the cathodes (negative sides) of the segment LEDs are connected together to a common pin. You drive a segment by applying a positive voltage to its individual anode pin. In a common-anode display, the anodes are common. You must check the datasheet's internal diagram to design the correct driver circuit (sourcing vs. sinking current).

Q: Why is there a peak forward current rating (I_FP) higher than the continuous rating (I_F)?
A> LEDs can handle short pulses of higher current without overheating, as there is time for the junction to cool between pulses. This allows for brighter display multiplexing or pulsed operation. The 1/10 duty cycle and 1kHz frequency are the defined safe conditions for this peak current.

11. Practical Design and Usage Case

Case: Designing a Simple Digital Voltmeter Readout
An engineer is building a 0-30V DC voltmeter. The analog-to-digital converter (ADC) outputs a BCD (Binary-Coded Decimal) signal. This BCD data needs to be converted to the 7-segment format using a decoder/driver IC (like a 7447 for common-anode displays). The ELT-512SURWA/S530-A3 display would be connected to the outputs of this driver IC. The engineer must:
1. Verify the driver IC's output current capability matches the display's I_F requirement (e.g., 10-20mA per segment).
2. Calculate and place current-limiting resistors between the driver IC outputs and the display pins if the driver does not have built-in current limiting.
3. Design the PCB layout according to the package dimensions, ensuring correct pin alignment.
4. Consider adding a dimming feature by using PWM (Pulse Width Modulation) on the driver's blanking or intensity control pin, which would modulate the duty cycle of the segments to control brightness without changing the current.

12. Principle Introduction

A seven-segment display is an assembly of seven rectangular LED elements (segments), arranged in a figure-eight pattern. By illuminating specific combinations of these segments, all decimal digits (0-9) and some letters (like A, C, E, F) can be formed. Each segment is an individual LED. In the ELT-512SURWA/S530-A3, these LEDs are made from AlGaInP semiconductor material. When a forward voltage exceeding the diode's threshold is applied, electrons and holes recombine in the active region of the semiconductor, releasing energy in the form of photons (light). The specific bandgap of the AlGaInP material determines the wavelength (color) of the emitted light, in this case, brilliant red. The light is then diffused and shaped by the white epoxy resin encapsulation to create the visible segments.

13. Development Trends

While through-hole displays like the ELT-512SURWA/S530-A3 remain vital for repair, hobbyist, and certain industrial markets, the overall trend in electronics is strongly towards surface-mount technology (SMT). SMT displays offer smaller size, lower profile, suitability for automated pick-and-place assembly, and often better thermal performance via direct PCB attachment. For high-brightness applications, newer materials like InGaN (Indium Gallium Nitride) are used for colors like blue, green, and white. However, for standard red displays, AlGaInP remains a highly efficient and cost-effective solution. Future developments may include displays with integrated drivers and controllers, reducing external component count, and the use of advanced plastics or coatings for wider viewing angles and enhanced contrast in sunlight.