LTC-5677KD-J LED Display Datasheet - 0.52-inch Digit Height - Hyper Red - 2.6V Forward Voltage - English Technical Document

1. Product Overview

The LTC-5677KD-J is a triple-digit, seven-segment LED display module designed for numeric readout applications. It features a digit height of 0.52 inches (13.2 mm), providing clear and legible characters suitable for a variety of electronic equipment. The device utilizes advanced AS-AlInGaP (Aluminum Indium Gallium Phosphide) epitaxial layers grown on a GaAs substrate to produce a Hyper Red emission. The visual presentation is characterized by a gray face with white segments, offering high contrast for improved readability. Its core advantages include low power consumption, excellent character uniformity, high brightness, and a wide viewing angle, making it ideal for applications in instrumentation, consumer electronics, and industrial control panels where reliable numeric indication is required.

1.1 Key Features

• 0.52 inch (13.2 mm) digit height.
• Continuous uniform segments for consistent appearance.
• Low power requirement.
• Excellent character appearance and high contrast.
• High brightness output.
• Wide viewing angle.
• Solid-state reliability.
• Luminous intensity is categorized (binned).
• Lead-free package compliant with RoHS directives.

1.2 Device Identification

The part number LTC-5677KD-J specifies a Common Anode, Hyper Red (AlInGaP) display with a right-hand decimal point configuration.

2. Mechanical and Package Information

The display follows a standard through-hole DIP (Dual In-line Package) form factor. Critical dimensional tolerances are ±0.20 mm unless otherwise specified. Key mechanical notes include a pin tip shift tolerance of ±0.4mm, limits on foreign material and ink contamination on the segment surface, restrictions on reflector bending, and bubble size within segments. The recommended PCB hole diameter for the pins is 1.30 mm. The module is marked with the part number (LTC-5677KD-J), a date code in YYWW format, the manufacturing country, and a bin code for luminous intensity categorization.

3. Electrical Configuration and Pinout

3.1 Internal Circuit Diagram

The device has a common anode configuration. Each of the three digits shares a common anode pin (pins 8, 9, and 12 for digits 3, 2, and 1 respectively). The individual segment cathodes (A through G, and DP for the decimal point) are connected to separate pins, allowing for multiplexed driving.

3.2 Pin Connection Details

• Pin 1: Cathode E
• Pin 2: Cathode D
• Pin 3: Cathode DP (Decimal Point)
• Pin 4: Cathode C
• Pin 5: Cathode G
• Pin 6: No Connection
• Pin 7: Cathode B
• Pin 8: Common Anode (Digit 3)
• Pin 9: Common Anode (Digit 2)
• Pin 10: Cathode F
• Pin 11: Cathode A
• Pin 12: Common Anode (Digit 1)

4. Absolute Maximum Ratings and Characteristics

4.1 Absolute Maximum Ratings (Ta=25°C)

• Power Dissipation per Segment: 75 mW
• Peak Forward Current per Segment (1 kHz, 10% duty cycle): 100 mA
• Continuous Forward Current per Segment: 25 mA
• Forward Current Derating from 25°C: 0.28 mA/°C
• Operating Temperature Range: -35°C to +105°C
• Storage Temperature Range: -35°C to +105°C
• Solder Condition: 1/16 inch below seating plane for 5 seconds at 260°C.

4.2 Electrical & Optical Characteristics (Ta=25°C)

• Average Luminous Intensity per Segment (I_V): Min. 5400, Typ. 10000 μcd @ I_F=10mA
• Peak Emission Wavelength (λ_p): 650 nm @ I_F=20mA
• Spectral Line Half-Width (Δλ): 20 nm @ I_F=20mA
• Dominant Wavelength (λ_d): 640 nm @ I_F=20mA
• Forward Voltage per Segment (V_F): Typ. 2.0V, Max. 2.6V @ I_F=20mA
• Reverse Current per Segment (I_R): Max. 100 μA @ V_R=5V (Note: for test only, not for continuous operation)
• Luminous Intensity Matching Ratio (Similar Light Area): Max. 2:1 @ I_F=10mA
• Cross-talk Specification: ≤ 2.5%

Note: Luminous intensity is measured using a sensor/filter approximating the CIE photopic eye-response curve.

5. Typical Performance Curves

The datasheet includes typical characteristic curves which graphically represent the relationship between forward current and luminous intensity, forward voltage versus forward current, and the variation of these parameters with ambient temperature. These curves are essential for designers to optimize drive current for desired brightness while ensuring reliable operation within thermal limits. The forward voltage shows a typical value around 2.0V at 20mA, with a positive temperature coefficient. Luminous intensity increases with forward current but designers must adhere to the absolute maximum ratings for continuous and pulsed operation to prevent accelerated degradation.

6. Binning and Categorization System

The LTC-5677KD-J employs a binning system for luminous intensity, as indicated by the "Z" bin code in the marking. This ensures consistency in brightness across different production batches. Devices are tested and sorted into specific intensity bins, allowing designers to select parts that meet precise brightness requirements for their application, thereby maintaining visual uniformity in multi-digit or multi-unit displays.

7. Reliability Testing

The product undergoes a comprehensive suite of reliability tests based on military (MIL-STD), Japanese (JIS), and internal standards. Key tests include:

• Operation Life (RTOL): 1000 hours at maximum rated current under room temperature.
• High Temperature/Humidity Storage (THS): 500 hours at 65°C/90-95% RH.
• High Temperature Storage (HTS): 1000 hours at 105°C.
• Low Temperature Storage (LTS): 1000 hours at -35°C.
• Temperature Cycling (TC) & Thermal Shock (TS): 30 cycles between -35°C and 105°C.
• Solder Resistance (SR) & Solderability (SA): Tests to ensure pin integrity during soldering processes.

These tests validate the display's robustness under various environmental and operational stresses.

8. Soldering and Assembly Guidelines

8.1 Automated Soldering

Recommended condition: Soldering at 260°C for 5 seconds, with the solder point located 1/16 inch (approximately 1.6 mm) below the seating plane of the display on the PCB. The temperature of the display body itself must not exceed the maximum storage temperature rating during assembly.

8.2 Manual Soldering

Recommended condition: Soldering at 350°C ±30°C, applied within 5 seconds, with the same 1/16 inch seating plane guideline.

Adherence to these profiles is critical to prevent thermal damage to the LED chips, internal wire bonds, or the plastic package.

9. Application Notes and Design Considerations

9.1 Typical Application Scenarios

This display is intended for ordinary electronic equipment including office automation devices, communication equipment, household appliances, instrumentation panels, and industrial controllers. Its high brightness and contrast make it suitable for applications requiring good visibility under various lighting conditions.

9.2 Design and Usage Cautions

• Absolute Maximum Ratings: Operation beyond the specified absolute maximum ratings for current, voltage, power, or temperature may cause permanent damage, severe light output degradation, or catastrophic failure.
• Current Limiting: External current-limiting resistors are mandatory for each segment or common anode line when driving with a voltage source to set the forward current (I_F) to the desired value, typically between 10-20 mA for optimal brightness and longevity.
• Multiplexing Drive: Due to its common anode, pin-per-segment architecture, the display is ideally driven using a multiplexing technique. This involves sequentially energizing each digit's common anode while presenting the cathode pattern for that digit's segments. Proper timing and drive current must be calculated to achieve the desired average brightness without exceeding peak current limits.
• Thermal Management: While the device has a wide operating temperature range, maintaining the junction temperature as low as possible within the application's constraints will maximize luminous efficiency and operational lifetime. Ensure adequate ventilation if used in high ambient temperatures.
• ESD Precautions: Although not explicitly stated in the provided extract, AlInGaP LEDs are generally sensitive to electrostatic discharge (ESD). Standard ESD handling precautions should be observed during assembly and handling.

9.3 Comparison and Differentiation

The LTC-5677KD-J differentiates itself through its use of AlInGaP technology for Hyper Red emission, which typically offers higher efficiency and better temperature stability compared to older GaAsP-based red LEDs. The 0.52-inch digit height fills a specific niche between smaller indicators and larger panel displays. The categorized luminous intensity (binning) is a key feature for applications demanding consistent visual performance across all digits and units.

10. Frequently Asked Questions (FAQ)

Q: What is the purpose of Pin 6 marked "No Connection"?

A: Pin 6 is electrically isolated and serves no function. It is present for mechanical symmetry and alignment in the 12-pin DIP package. It should not be connected to any circuit.

Q: How do I calculate the current-limiting resistor value?

A: Use Ohm's Law: R = (V_supply - V_F) / I_F. For a 5V supply, a typical V_F of 2.0V, and a desired I_F of 10mA: R = (5V - 2.0V) / 0.01A = 300 Ω. Always use the maximum V_F from the datasheet (2.6V) for a conservative design to ensure I_F does not exceed limits.

Q: Can I drive this display with a constant current source?

A: Yes, a constant current source is an excellent way to drive LEDs as it ensures consistent brightness regardless of minor variations in forward voltage. The current should be set to the desired I_F (e.g., 10-20 mA) and must comply with the maximum continuous current rating.

Q: What does the "Z" bin code mean?

A: The "Z" code represents the specific luminous intensity bin the device belongs to. The exact μcd range for each bin code is typically defined in a separate binning specification from the manufacturer. Designers should consult this information to ensure brightness uniformity.

11. Packaging Specification

The devices are packaged in anti-static tubes or trays suitable for automated assembly equipment. The packing specification details the quantity per tube/tray, orientation, and labeling to ensure correct handling and inventory management.