CFL hack

bhankiii,

Did't they have beer signs for something like this, if not you may be on to something.

phoenix911

Electroman might know...he like opening up chargers and stuff..(maybe PM him, he might be having a cat nap or on hol)

Prob' is it will be dense surface mount circuitry and difficult to work out what's what.

Del

I haven't actually done any measurements inside a working CFL, But I suspect they are rather similar to the fluorescent lamps used as backlights in laptop computers. These use about 300 Volts, so they have a tiny switching power supply to step up the battery voltage. Yes, they do use high frequency in order to be able to use a very small transformer.

On the other hand, for your project, you need to reduce the voltage, not increase it. It would certainly be possible to wind the transformer to produce a step-down instead of step-up, so give it a try!

Yeah - I think that will be the plan - rewinding the transformer.

taken from an NXP app note for a CFL chip.

The steady state operating point of a 13W PLC lamp is approximately: a lamp voltage of 75 V, a lamp current of 170mA and a lamp power of 13W.

http://www.google.com.au/search?hl=en&q=cfl+app+note&btnG=Search&meta=

first link,

that particular one is not the one I was looking for as it uses a chip, the simpler solution would be to use the more common 2 transistor version 5th link in the above search, the self oscillating one.

bear in mind that these circuits are not isolated .. it should be achievable without too much hassle though since the transformer needs rewinding anyway.

Sweet - thanks for the link.