TFT-LCD Backlight (6x Series LEDs) Driver

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I have been looking around for a bit now, and I cannot find a suitable DC converter for my application. I am in need of a high-efficiency buck-boost converter that can take my 7.4v LiPo output and output 1.8v, 3.3v, 5v, and a suitable voltage to drive 6x LCD backlight series LEDs.

I would like to know what you guys have used successfully in the past.. Most suitable buck-boost converters I see around have a max Vin of 5.5v...

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Ok nevermind, finally found a suitable 20v output converter, for those interested it's a LM27313...

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Another question, related...

How do you folks usually go around sequencing the power supplies for a TFT panel? The datasheet for most of them seems to indicate that each rail has to startup and shutdown in order, for example:

Startup
1- DVDD (3.3v)
2- AVDD (5v)
3- Delay 200ms
4- TFT Backlight (20v)

Shutdown
1- TFT Backlight (20v)
2- Delay 200ms
3- AVDD (5v)
4- DVDD (3.3v)

I imagine it is fairly safe to activate DVDD and AVDD at the same time, but I do not know how to delay 200ms before activating the backlight or after deactivating it... I have looked the major suppliers for power sequencers, but none of them can handle 20v. I do have a shutdown line on the DC converter, if held low will shutdown the rail, but I am unsure how to hold it low until the other rails have started, then delay 200ms before putting it high again.. That's not even mentioning the shutdown sequence..

I would appreciate the help here, it's my first project involving a TFT... :)

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What are you using to control the TFT?

Could you use some spare I/O from that to do sequencing (and allow you to turn the backlight off as needed)?