DIY Power Bank with Plasma Lighter

A power bank with a built-in plasma lighter. It charges phones from a rechargeable battery and also produces a flameless plasma arc for lighting candles or stoves.

Rechargeable battery and 12 V power adapter / step-down transformer supply the circuit; a regulator gives the controller and sensors a steady 5 V. The Arduino Uno R3 reads the inputs, runs the decision logic written in C/C++ and drives the outputs. The LEDs indicate status.

The Uno uses the ATmega328P: 8-bit, 16 MHz clock, 32 KB flash, 2 KB SRAM, 14 digital I/O pins (6 PWM) and 6 analog inputs with a 10-bit ADC.

It limits the current to a safe value (about 10–20 mA). Without it, the LED would draw too much current and burn out. R = (supply voltage − LED voltage) ÷ current.

Backup time (hours) ≈ battery capacity (Ah) × voltage × 0.8 efficiency ÷ load power (W). For example, 12 V 7 Ah at 20 W gives about 3.3 hours.

A transformer steps down the voltage, a bridge rectifier converts AC to pulsating DC, a capacitor smooths it and a 7805 regulator gives a steady 5 V.

Using P = V × I for each load, adding a margin of 20 to 25%. Battery capacity is the energy needed per day divided by the battery voltage and allowable depth of discharge.

A fuse against short circuit, relays or optocouplers to isolate the control side from the power side, flyback diodes across inductive loads such as relays and motors, and software limits that cut off on over-current or over-voltage.

Efficiency = output power ÷ input power × 100. We measured input and output voltage and current with a multimeter at different loads and tabulated the results in the report.

The input section senses the real-world quantity, the Arduino Uno R3 processes it according to the program, and the output section displays the result and drives the actuators. The power supply section feeds every block.