Anonymous
Anonymous asked in Science & MathematicsEngineering · 9 years ago

# How I turn a DC current on and off really fast?

I want to make a DC current (from a battery) oscillate between full voltage and zero voltage (not negative) really quickly, at least 30 Hz.

I tried using an electromechanical switch, but the current from the battery is too low to produce any appreciable electromagnetism, so the switch didn't work.

I tried using a transistor circuit, but it didn't work either. Again, I think it's because the current is too low to use with the transformer that's used to regulate the transistors.

Anyone else have a solution? I'd rather have it be solid-state, but if the solution needs moving parts that's fine, as long as it works.

Relevance
• Anonymous
9 years ago

Hi My Friend,

You may pick an oscillator circuit, either using 7414 or 555 to generate the ON/OFF potential. And apply this ON OFF signal to a Solid State Relay (SSR).

It can build a super fast ON OFF switch in the DC world.

OSCILLATOR:

http://www.vishay.com/docs/81646/vo14642a.pdf

SSR:

http://www.vishay.com/docs/81646/vo14642a.pdf

Hopefully, it helps you to create the circuit!

• Anonymous
9 years ago

Depends upon the battery voltage, but a simple circuit that would work for most batteries, 12 V or less would be to use a 555 multivibrator chp (and a resistor and a capacitor for timing) driving a simple transistor. The transistor would be selected based upon required current.

• 9 years ago

What you need is a transistor switch. If current required is less than 200mA, (an important point that you have not indicated), a 555 is a good solution. If higher current is required, you can drive the load with a transistor used as a switch, driving its base through a resistance from 555 output.