Dual-Voltage Rechargeable Torch Light

The Dual-Voltage Rechargeable Torch Light is an intermediate-level analog electronics project designed to operate from an AC mains power supply. The circuit integrates an input connector (CON1) that connects to the AC mains, utilizing two 0.82µF mylar capacitors (C1 and C2) alongside a resistor network (including R2 and R3) to drop and safely limit the alternating current. A bridge rectifier constructed from four 1N4007 rectifier diodes (D1-D4) converts this AC voltage into a pulsating DC voltage. To protect downstream components and establish a stable reference, 4.7V Zener diodes are employed for voltage regulation, while filter capacitors (C3 and C4) smooth out remaining ripples to provide a cleaner DC output. This regulated DC supply is used to charge two 3.7V 860mAh lithium-ion rechargeable batteries (BATT.1 and BATT.2) housed on the custom PCB. A DPDT switch (S1) gives the user control over the power delivery and lighting modes. For illumination, the system features a versatile lighting array containing two standard 5mm LEDs (LED1 and LED2) alongside two high-power 1-watt white LEDs (LED3 and LED4), allowing the user to switch between different brightness levels depending on their illumination requirements.