## Technical Overview of HLMP-CE27-R0C00 The **HLMP-CE27-R0C00** is a high-performance, precision optical performance T-1 ¾ (5mm) Cyan LED manufactured by Broadcom (formerly Avago Technologies). It is part of a series designed for high light output and reliability in outdoor and industrial applications. --- ### 1. Key Technical Specifications | Parameter | Specification | | :--- | :--- | | **Color** | Cyan (Blue-Green) | | **Dominant Wavelength** | 505 nm | | **Luminous Intensity (Iv)** | 1150 – 1500 mcd (typical) | | **Viewing Angle** | 23° | | **Forward Voltage (Vf)** | 3.2V (Typical) / 4.0V (Max) | | **Forward Current (If)** | 30 mA (Recommended) | | **Package Type** | T-1 ¾ (5mm) Round Through-hole | | **Lens Type** | Untinted / Non-diffused (Clear) | --- ### 2. Electronic Characteristics & Design #### Optical Performance * **Cyan Spectrum:** The 505 nm wavelength is specifically chosen for applications requiring high visibility and color distinction, often used in traffic signaling or decorative lighting where standard green or blue is not optimal. * **Narrow Beam:** The 23-degree viewing angle concentrates the light, making it suitable for directional indicators and long-distance visibility. #### Electrical Constraints * **InGaN Technology:** The chip uses Indium Gallium Nitride (InGaN) technology, which provides superior efficiency and high brightness compared to older LED technologies. * **Thermal Management:** The device is rated for an operating temperature range of **-40°C to +80°C**. Proper current limiting (using resistors) is essential to prevent thermal runaway. * **Reverse Voltage:** The device has a maximum reverse voltage of **5V**. Designers must ensure the LED is not subjected to high reverse transients. --- ### 3. Common Applications * **Traffic Signals:** Used in pedestrian and vehicle signal heads due to its high brightness and specific color compliance. * **Commercial Signs:** High-intensity backlighting for outdoor advertising. * **Variable Message Signs (VMS):** Used in highway and informational displays. * **Industrial Indicators:** Status lights that must remain visible under high ambient light (sunlight). --- ### 4. Implementation Circuit Example To drive the HLMP-CE27-R0C00 from a 5V DC source at 20mA, you can use the following calculation for the current-limiting resistor ($R$): ```python # R = (V_source - V_forward) / I_forward # R = (5V - 3.2V) / 0.020A # R = 1.8V / 0.020A = 90 Ohms ``` *Recommended Resistor: **91 or 100 Ohms** for safety.*