The 555 timer IC is a versatile electronics device because it can be used in different electronics circuits, from power supply, to motor control signals, to timing signal, pulses with different pulse witdth, that is PWM(pulse width modulation) signals. I had written in my earlier blog post how 555 timer can be used in building a 555 timer boost converter which takes lower input dc voltage and provides higher output dc voltage.
Here I wanted to write a note on how a 555 timer can be used to build a voltage doubler. Say for example if the input dc voltage to the 555 timer IC is Vcc then the output voltage will be 2xVcc. So if input voltage is say 5V then the output should be 10V. This is why it is called a voltage doubler circuit, because it doubles the input voltage. So this essentially is kind of boost converter because the output voltage is higher than the input voltage.
The following shows the circuit diagram of 555 timer based voltage doubler.
The input voltage in the above circuit is 5V from a battery(say). The C1 capacitor is connected between the +ve and -ve terminal(ground) of the battery in order to remove noise. The R1 and R2 forms a voltage divider whose junction is connected to discharge pin 7, trigger pin 2 as well as the threshold pin 6. The reset pin 4 and the power pin 8 are connected to the +5V rail. The output pin 3 is connected to a 10uF capacitor and two diodes 1N4148 in reversed order as shown in the diagram.
I designed the circuit in proteus software for simulation. From the simulation what I found is that the output voltage rises to 8V when the input voltage is 5V. I have to actually build this circuit on breadboard to find out if in reality the output voltage is 10V or not. That is to check whether it is the simulation which did not give 10V as expected.
The following is the video on this simulation fo the 555 timer voltage doubler circuit.
