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I use 30 inch monitor Samsung 305t that uses 16 CCFL lamps as a direct backlight. The driver consists of 8 HV transformers, each of them running 2 lamps in series. Some info about the lamps:

enter image description here

As you can see the voltage is about 1700 volts with typical current of 6mA.

The problem is the backlight is too bright. In fact I own 2 of these monitors. One of them is very bright and the other a bit dimmer but still very bright. I would like to dim the backlight by stealing some current from the lamps but I am not sure if this is possible?!? Dimming the backlight would allow me to use higher PWM %, which produces less flicker. The PWM is fixed to 254Hz. Question: Can I add some resistors to steal some of the current that goes into the lamps? Are they still going to strike successfully? I would be happy to redirect 1/2 of the current into a 5W resistors. Any other ideas that can limit the amount of light?

Komental
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    So why not just reduce the brightness using the PC? – Dirk Bruere Jul 16 '21 at 17:08
  • @DirkBruere I have 2 reasons. 1 - it's not enough 2- changing the settings in PC is changing the image quality but I do graphics on this monitor and this is unacceptable. Changing the brightness setting changes the gamma of the monitor. IDK if you understand gamma but in simple words, when you change brightness in software you loose detail in shadows. – Komental Jul 16 '21 at 19:20

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