A stun gun is a device that produces a high voltage, low current signal and is primarily used as a weapon to stun or shock a target in order to weaken or immobilise it. However, while designing the circuit, keep in mind that stun guns are illegal in several countries. Because this is a lethal weapon capable of rendering a person psychologically incapacitated. A 9V battery is commonly used to power it. We’ll make a stun gun circuit with a 555 Timer to generate a current fluctuation signal, a voltage multiplier with a transformer, and a multi-stage arrangement of voltage doublers with capacitors and diodes.
- Stun Gun Circuit Operating Principle:
- Stun Gun Circuit Diagram:
- Stun Gun Circuit Design:
- How to Operate Stun Gun Circuit?
- Stun Gun Applications:
- Limitations of Stun Gun Circuit:
Stun Gun Circuit Operating Principle:
The stun gun circuit works on the same idea as a traditional stun gun. The frequency of an oscillating signal generated by a 555 Timer is determined by the external passive elements connected to the Timer. A step up transformer converts the low current electric pulses into a high voltage signal, which is then amplified by a voltage multiplier circuit. The voltage multiplier circuit is made up of several voltage doubler stages, each with two diodes and two capacitors. The Villard doubler method is used in the voltage doubler circuits. The number of stages has a direct relationship with the output voltage.
Stun Gun Circuit Diagram:
Stun Gun Circuit Design:
In fact, two phases of design are required here: astable multivibrator design and voltage multiplier design.
The output voltage must be determined first while designing the circuit. Our goal is to generate a 10KV DC voltage from a 1000V input power.
The result of the equation is
Where S is the number of stages, Vout = (2Vin + 1.414)S.
It would take around 5 stages of voltage doubling to get a voltage of 10KV.
We create a 5-stage voltage multiplier circuit that generates a 10KV output voltage. Each capacitor should have a voltage rating of at least 1000V because the input voltage is around 1000V. We need a 2500V, because the working frequency is low, on the order of Hertz.
We use a 555 Timer to design the astable multivibrator circuit. Passive external components must be chosen while designing a 555 Timer in astable mode.
We compute R1 to be around 1.44K, R2 to be around 720 Ohms, and C1 to be around 10uF, assuming a maximum operating frequency of 50Hz and a duty cycle of 75%. We’ll use a 2K potentiometer, 720 ohm resistor, and a 10uF capacitor in this example. A MOSFET IRF530 is employed because this is a low frequency operation.
How to Operate Stun Gun Circuit?
The astable action of the 555 Timer begins as soon as the switch S1 is pressed. A low-current pulsing electric signal is generated, which is stepped up to a voltage of roughly 1000V using a step up transformer. A MOSFET switch receives the signal from the Timer.
- Capacitor C3 charges through forward biassed diode D1 during the first positive half cycle. The charge is stored since the capacitor has no discharge channel. At the end of a half cycle, the voltage is equal to the AC input peak value.
- Diode D2 is forward biassed during the negative half cycle, while capacitor C4 charges through C3 and D2. A voltage equal to twice the input AC voltage at the end of the cycle.
- Diode D3 is forward biassed again during the following positive half cycle, and capacitor C5 charges. Diode D4 is forward biassed again during the following half cycle, and capacitor C6 charges. At point 2, a voltage equal to 4 times the input peak voltage is obtained at the end of the cycle.
- The same procedure applies for other two stages and finally a voltage equal to 10 times the input voltage is obtained at point 5.
Stun Gun Applications:
- It can be used for security purpose for individuals from intruders.
- It can be used as protection from animals.
- It can be used as modern warfare equipment.
Limitations of Stun Gun Circuit:
- The circuit is dangerous since it produces high voltage pulses, and it should be built on hardware with extreme caution.
- Because this high voltage, low current signal can send shock waves through the body, upsetting the neurological system, it should not be touched with bare hands.
- Factors like as corona discharge and stray capacitance are not taken into account while constructing the circuit, which could damage the output.
- This circuit should never be used in the company of people who have heart problems.
- It’s actually to build a 9:1000 step up transformer at low frequency, and it’s rather complicated.