Positive voltage to negative voltage converter

[exxos]

Thought I would post this here as it is a interesting and simple method of generating negative voltages. There are dedicated ICs to do this kinda stuff as well.

REF : https://www.circuitstoday.com/positive- ... -converter


This circuit diagram shows how to obtain a negative voltage from a positive voltage supply. Another advantage of this circuit is that, the negative voltage together with the original positive supply can be used to simulate a dual supply. The circuit is based on timer IC NE555. The NE555 is wired as an astable multivibrator operating at around 1 KHz. The square wave output if available at pin no 3 of the IC. During the positive half of the square wave, capacitor C3 charges through diode D2.When the output of IC is at zero the C3 discharges through diode D2 and the capacitor C4 gets charged. As a result of this the voltage at the junction of the anode of D1 and cathode of C4 will be always negative with respect to the ground.

positive-to-negative-voltage-converter.png

[Badwolf]

Here's an EEVblog video on the inverting charge pump. He takes 20 mins to say the same thing. ;)



BW