The 1-Digit 7-Segment Green Colour 4-inch Common Cathode LED Display is a large-format numeric display module engineered for high-visibility visual readouts in industrial automation, commercial signage, and outdoor electronic timing systems. Featuring an oversized 4.0-inch (101.6mm) character height with vibrant green GaP/InGaN LED illumination, this display integrates multiple LED dies wired in series per segment to ensure uniform light distribution, sharp contrast, and long-range legibility up to 100 meters away. Encapsulated in a rugged epoxy resin package with a high-contrast black face and white diffused segment bars, the common cathode configuration ties all negative LED terminals together to a common ground rail while individual segments (A through G and Decimal Point) are driven via high-side source driver circuits. It is widely used in queue management token systems, production line counters, industrial scoreboards, large digital clocks, and weighbridge indicators.

Specifications

• Part Number / Model: 40011BG / 40101BG (Standard 4.0-inch 1-Digit 7-Segment Series)
• Display Type: 1-Digit 7-Segment Numerical LED Display with Decimal Point (DP)
• Digit Height: 4.0 Inch (101.6 mm)
• Module Dimensions: 122.0 mm (Height) × 90.0 mm (Width) × 15.0 mm (Thickness) ±0.5 mm
• Circuit Polarity: Common Cathode (CC - Shared Negative / Ground Rail)
• Emitted Light Color: Pure Green / Yellow-Green
• Dominant Wavelength (λd): 520 nm to 570 nm (Peak Wavelength λp ≈ 565 nm)
• Die Configuration per Segment: 4 to 5 LED dies in series per segment (A–G); 2 LED dies in series for Decimal Point (DP)
• Forward Voltage Drop per Segment (VF - Segments A to G): Typ. 8.0V to 10.0V / Max. 12.0V (at IF = 20mA)
• Forward Voltage Drop for Decimal Point (VF - DP): Typ. 4.0V to 4.4V / Max. 5.0V (at IF = 20mA)
• Continuous Forward Current per Segment (IF): 20 mA (Continuous) / Max. 30 mA
• Peak Pulse Forward Current (IFP): Up to 100 mA (Duty ratio 1/10, 0.1ms pulse width)
• Reverse Breakdown Voltage per Segment (VR): 15V to 25V (Segments A–G) / 10V (DP)
• Luminous Intensity (Iv): 60 mcd to 120 mcd per segment (at IF = 20mA)
• Face & Segment Color: Black Surface Face with White Diffused Translucent Segment Lenses
• Power Dissipation per Segment (Pd): Up to 250 mW (Segments A–G) / 100 mW (DP)
• Operating Ambient Temperature (Topr): -25°C to +85°C
• Storage Temperature Range (Tstg): -30°C to +85°C
• Pinout Configuration: Standard 10-Pin Through-Hole DIP Header (Pins typically arranged top/bottom: Common Cathode pins, Segments A, B, C, D, E, F, G, and DP)

Features

• Large 4.0-Inch Digit Profile: Massive character height provides clear readability and visual impact from long distances in bright industrial bays or outdoor display panels.
• Uniform Green Illumination: High-efficiency green LED dies emit bright, even illumination across all segments with low power consumption and long operational lifespan.
• Common Cathode Architecture: Simplifies high-side switching using high-voltage source driver ICs (such as UDN2981 / MIC2981), high-side P-channel MOSFETs, or PNP transistor arrays.
• Multi-Die Series Configuration: Built with matched series-connected internal LED dies per bar to eliminate hot spots and ensure consistent brightness across the entire digit.
• High-Contrast Industrial Housing: Matte-black front panel combined with milky-white diffused lenses maximizes readability under ambient light and direct sunlight.

Common Applications

• Queue Management & Token Displays: Customer numbering systems and counter callout screens in banking halls, airports, and clinics.
• Factory Production Tally Boards & Scoreboards: Real-time unit counters, target vs. actual production monitors, and sports timing scoreboards.
• Fuel Dispenser & Price Signage: High-visibility price boards and volume readout panels in fuel stations.
• Truck Scale & Weighbridge Displays: Large remote weight indicators for industrial weighbridges, platform scales, and crane monitors.
• Large-Format Digital Clocks & Timers: Public gym workout timers, countdown clocks, and race lap time displays.

Usage Tips

• High-Voltage Drive Supply (+12V Rail): Segments A–G contain 4 to 5 LED dies in series requiring a forward voltage drop of 8.0V to 10.0V. **Do not power segments directly from 3.3V or 5V logic rails**; use a regulated +12V DC power source.
• High-Side Driver Selection: Since this is a Common Cathode display, drive segment anodes from a 12V rail using high-side source driver ICs like the **UDN2981 / MIC2981** or P-channel MOSFET / PNP transistor arrays triggered by 3.3V/5V microcontroller outputs (Arduino, ESP32, STM32).
• Separate Resistor Sizing for DP: The Decimal Point (DP) contains only 2 LED dies in series (~4.0V to 4.4V drop) compared to segments A–G (~9.0V drop). Always calculate and use a higher resistance value for the DP series resistor to prevent overdriving the DP segment.
• Current-Limiting Resistor Calculation: For Segments A–G powered from +12V at 20mA: R_seg = (12V - 9.0V) / 0.02A ≈ 150Ω (rated for 1/4W). For the Decimal Point (DP): R_dp = (12V - 4.2V) / 0.02A ≈ 390Ω.
• Common Ground Connection: Ensure the Common Cathode pins are securely grounded to the system power ground plane to handle the combined return current of all lit segments (up to ~160mA continuous when displaying '8.').

Datasheet