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Negative Ion Generator by 555

The design of the Negative-Ion Generator is fairly straightforward (see Fig. 1). The circuit is a high voltage generator. It contains a standard 555 timer that’s used to generate square-wave pulses. The pulses are applied to the base of the TIP120 NPN Darlington transistor. The Darlington provides sufficient current to the base of the 2N3055 power transistor to turn it on.

Source:http://www.uoguelph.ca/~antoon/circ/hv/niongen/niongen2.html
Thank you.

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Categories: High voltage Tags: 555, high voltage, negative voltage

100 Seconds Duration On Switch with Touch Control by 555

This is a touch control switch which keeps the circuit on about 100 seconds after touching the plate connected to the 2 numbered pin. At the end of this time duration, relay releases and the circuit gets to off position.

The impedance of the trigger input of the 555 timer IC is very high and the inductive voltage on the human body is enough to trigger it. The circuit works based on this principle. You can use a piece of metal as a plate. The circuit can be used in toy circuits, buzzers or any project that is suitable. You can adjust the duration time by changing the R1 and C1 values.

Power On Delay Circuits by 555

These circuits will delay the application of power to a second circuit using mechanical relays or transistors. Other output control devices could also be used.