Thoughts: Expander board for Olinuxino-A20 (Multimedia deck)

[deskwizard]

Good evening,

I started work on a little expander board to connect all the peripherals I need on the same board.
I am by no means a professional, so if anyone have thoughts/spots errors I made please let me know.
I am likely going to have to have at least 5 made, so ... if anyone is interested, hit me up.

I am adding:

DS1338 RTC (like 1307 but 3.3v compatible, with battery backup) - Little 1307 breakout board from ebay, I swapped the chip

Serial GPS (going to need some play with the sources to make it work, had done it before I lost everything)

RDA5807M FM tuner breakout from ebay (cheaper than buying the chips.. go figure. Working on Tuner apk right now)

LCD with touchscreen (Kit from ebay, 1280x800 Hannstar HSD070PWW1-B01) Ditching the converter board that came with it, will connect directly on LVDS. Only model I found that works down to -20deg C.

Schematic:
http://imgur.com/nQa8viJ

If anyone has time to do a little double check, especially on the FET sections, I'd greatly appreciate.

Thanks in advance,

DW

[ebelouet]

Hi,

Have you make your board extensions for lvds board ?

Sincerely
Eric

[deskwizard]

Hi Eric,

No I have not, I suffered data loss and I have to remake everything from scratch, and sadly the LCD I was going to use can't work with the A20 (as far as I know, I couldnt make it work).

I am unsure at the moment what the final board will contain, ie if I will let go of the LVDS part and just have the audio part, only time will tell.

I'll try to keep in mind your interest and I'll share it with you if I decide to go that way.

I know Dave-at-axon was working on an LVDS board also, perhaps he could give you helping hand.

Thanks,

DW

[dave-at-axon]

Good timing guys,

I just received the PCB's and the part this week and will build and test the LVDS driver and receiver next week.

I am not going to use the LVDS output from the A20 and instead have created a small board that plugs into the A20 and has a TI LVDS driver and then I have a receiver on the LCD side that converts this back to RGB.

The reason for this is that I have timing issues when using the damn ribbon cable due to the poor location of the DOTCLK line and no protective ground on either side. With this new driver I should be able to use a 150mm cable with no issues at all.

I'll post back next week once I have it all up and working.