Electronic Starter for Fluorescent Tube

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First you should understand that a starter is old technology. It is used mostly with magnetic ballasts and its purpose is to pre-heat the coils inside the fluorescent lamp prior to ignition voltage being applied. The device is a type of thermal switch which is in parallel with the fluorescent lamp so that before the lamp is started, it will turn on and heat a bi-metallic switch causing it to close, thereby completing a circuit consisting of a lump of inductor and two lamp coils in series. While the bi-metallic switch closes, it extinguishes the plasma in its little bottle and the bi-metallic cools and opens the circuit. Up to this point, the process can be implemented in solid state without a problem.

But, when the bi-metallic strip opens the above mentioned circuit, it interrupts current flow through the inductor. In doing so, a very high voltage is impressed across the lamp (easily a 1000 volt spike) which is enough to begin current flow through a 4 foot tube of mercury laden atmosphere with a noble gas buffer.

So if a high voltage spike will start a lamp (with an initial resistance of several megaohms) then your electronic component would have to be able to survive the same spike since it is in parallel with the lamp. The problem is that most electronic components have transistors and other components contained in a very small space and the electrical spike will just burn another path right through your component. Not good for repeat business......if you know what I mean.

New ballast technology uses a fairly high open circuit voltage to begin the process of ionization of the gas inside a fluorescent lamp at rest. In addition, they use a high frequency drive that changes frequency as the lamp turns on. The resistance of the lamp causes the resonant frequency of the oscillating circuit to shift (variable Q) as it comes up to full current. These new electronic ballasts save about 4 watts per fluorescent lamp circuit. They are the only future in fluorescent lamp technology.