Pocket white-LED torch is power efficient

12,956

Circuit Image

This single white LED torch can be housed in an empty glue stick tube and has a long rechargeable battery life.

The proposed circuit design features a compact LED torch that utilizes a single white LED as the primary light source. The housing for this device is derived from a repurposed glue stick tube, which provides a lightweight and portable structure. The design incorporates a rechargeable battery, ensuring extended usage without the need for frequent replacements.

The circuit consists of several key components:

1. **LED**: A single white LED is selected for its efficiency and brightness. The LED operates at a forward voltage of approximately 3.0-3.2V and requires a current of around 20mA for optimal performance.

2. **Power Supply**: A rechargeable lithium-ion battery, typically rated at 3.7V, is employed to power the LED. This battery type is favored for its high energy density and ability to be recharged multiple times.

3. **Resistor**: To limit the current flowing through the LED and prevent damage, a current-limiting resistor is included in the circuit. The value of this resistor can be calculated using Ohm's Law: R = (V_battery - V_LED) / I_LED. For example, with a 3.7V battery and a 3.2V LED at 20mA, the resistor value would be approximately 25 ohms.

4. **Switch**: A simple on/off switch is integrated into the circuit to allow the user to control the operation of the torch easily.

5. **Charging Circuit**: To facilitate recharging of the lithium-ion battery, a charging circuit can be included. This may consist of a microcontroller or dedicated charging IC that manages the charging process, ensuring safety and efficiency.

The entire assembly can be encased within the glue stick tube, with the LED positioned at one end to provide illumination. The other end can be sealed or fitted with a cap that allows access to the charging port, ensuring that the torch remains functional while maintaining a sleek and compact design.

This design not only promotes sustainability through the reuse of materials but also offers a practical solution for portable lighting needs.This single white-LED torch can be housed in an empty glue-stick tube and has a long rechargeable-battery life.. 🔗 External reference