LED Flashlight with Rechargeable Capability

A high intensity red jumbo LED is being used on this project as the rechargeable flashlight provides a moderate source of light that will always be available without the need to replace batteries of change light bulbs.

The device may be left plugged in a 110 VAC wall outlet and be ready for use but when the flashlight is not plugged in an AC outlet, the current flow from battery B to Q1 is prevented by the diode D4. The negative terminal of the battery B is directly connected to the emitter of transistor Q2 while the base is positively polarized via R5. The base-emitter junction of the transistor is directly polarized in this way, which turns ON the collector-emitter junction and the current is allowed to flow from battery B to main LED.

The charging LED indicator is ON while the main LED is OFF when the flashlight is plugged and charging. One feature of this flashlight is that no bulb will ever burn while the rechargeable NiCd battery may be of the camera type with a size a little bit bigger than the regular AA batteries which run for 3-5 hours.

Rest of the project