Mobile Internet is the most popular media for social networking and picture and video sharing. Mobile phones with multimedia as the core are seizing the market share of mobile phones with call as the main part, which will lead to the development of mobile phones in the direction of larger size and higher resolution color displays. In addition to the changes of the display screen, the mobile phone is also becoming a high-quality digital camera, and it requires special lighting functions, which can take pictures and take pictures in dim lighting environments. In order to obtain better image effects, the flash function of the mobile phone camera has become increasingly important.

But we all know that flash lamps actually consume a lot of power, and when the flash lamp is turned on, the battery current and power will suddenly increase. Mobile phone batteries have strict peak current limits, for example, flash devices that consume too much current may cause the phone to shut down. On the other hand, as the resolution of the mobile phone camera doubles or triples, the pixel size needs to be reduced to accommodate more pixels, and lower pixel size requires more light. To get more light means that the flash must output more light, but the mobile phone battery obviously cannot supply. What should we do?

So industry experts add Farad capacitor between the battery and the load, optimize the charging of Farad capacitor, use a small drive to make the Farad capacitor work, and use the Farad capacitor device to provide flash current.

In this way, the mobile phone will not shut down due to the sudden increase of current and power when the flash light is turned on.

In addition to LED flash, there are a few high-end camera phones that use xenon flash technology. However, for the increasingly compact mobile phone market, the thin and light characteristics of the Farad capacitor have proved to be more attractive than the heavy xenon camera module. Xenon flash can generate high light power in a short time, while farad capacitor can generate less light power in a long time. In terms of light output or light energy, the two technologies are comparable in capturing high-quality images.

The growing mobile phone video recording function requires the use of a separate xenon flash LED module, so that video can be recorded in dim light conditions, while the Farad flash driver can use the same flash LED to provide video lighting. The Farad capacitor LED flash driver does not need a high-voltage trigger to start flashing, nor does it need to store a lot of energy in a large electrolytic capacitor. This electrolytic capacitor is close to the human ear during mobile phone calls. All these advantages make it a safer alternative to xenon technology. Even so, people in the industry always believe that the photo effect of xenon flash is much better than LED flash.

Although we deal with mobile phones every day and turn on flash to take photos when necessary, I didn't expect that there would be so much knowledge in it.

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