12.1 Inch Display Question

Dyltone, you’re the only one – in all of the 12.1 inch display forum threads – who’s owned both the CCFL and LED-backlighted displays who’s actually written something like that. THANK YOU! Because of you, I just ordered one.

I’d like to note that there are some GREAT deals on these displays on ebay if you know how to look. This is the one I bought:

Samsung LTN121AT10 $13.00 with shipping (used by “grade A”)
http://www.ebay.com/itm/222318104781

Yes, it’s used, but you can find them new for $30 including shipping:
[link removed because forums.pimoroni.com tells me “new users can only put 2 links in post”
5 still available, but if he runs out, search ebay for LTN121AT10 or LTN121AT11-801. There are still some used LTN121AT10 “grade A” panels for under $20 from other sellers.

Both are matte finish, which I prefer. These appear to come from the Google CR-48 and Samsung XE500C Chromebooks, so you could search for screens for those, too.

Data sheets confirm the specs are correct. I’d link the data sheet PDFs here but forums.pimoroni.com is telling me that “new users can only put 2 links in post”

A lot of times ebay sellers aren’t saying if the screen is CCFL or LED backlit. In that case, look for the data sheet online by googling “model number + PDF”.

I haven’t found the controller board yet, but have asked a few ebay sellers if they can program boards for me. Many of the controller board sellers say to do this if you cannot find the exact model you need. Be sure to specify HDMI+AUDIO OUT since we get HDMI from the Pi. Some of the boards are VGA or DVI only. The HDMI ones look to be between $20-$30.

2 Likes

LTN121AT10 new for $30 including shipping (this seller has 5 available):
http://www.ebay.com/itm/SAMSUNG-LTN121AT10-LAPTOP-LCD-SCREEN-12-1-WXGA-LED-SINGLE/131656357851

Dyltone, how did you decide between the http://petrockblog.storenvy.com/products/13969704-powerblock and the ATXRaspi?

Pretty simple… as I said, I was mirroring Paul’s build I linked above. No other reason as I think they are similar in features.

I was looking closer at the panels that you linked to, be careful as they list as WXGA 1280x800 16:9 vs the XGA 1024x768 4:3 panel I purchased.

If you do have a source for http://www.panelook.com/LTN121XL01-N03_Samsung_12.1_LCM_overview_20074.html panels, please let me know as I will purchase an additional one as backup for those prices.

Just purchased one of thse from ebay for about 30 bucks with expedited shipping from new york.

It’s not LED backlit but still offers very nice viewing angles and response times (slightly better than the LTN121XL01 you listed) though the contrast and brightness aren’t as good.

I’m currently using this one

the viewing angles are crap and there’s a bright glow from the bottom of it. It’s also very dim with terrible contrast.

The only thing it has going for it over the 8" is size. I wish I’d done more research when looking for 12 inch screens, the one you have plus the driver board would have been well worth the extra 30-40 bucks.

I’m hoping this LTN121XP01 works with the driver board that came with the one I got from ebay. It appears to be the same board you listed and I already have the driver board for ccfl backlighting.

I’ll report back with results, hopefully it looks better than my current 12 inch.

Let us all know how it works out. I hope that not all CCFL’s are created equal in this case. Good Luck… May the Force be with you.

Got the new screen from ebay. PVA panel, great viewing angles, good contrast, decent brightness (more than good enough for an arcade cabinet you’ll be close to indoors) and there’s little to no light bleed at the bottom of the panel.

I had to cut off and bend some mounting lugs so it would fit, that was easy though. One set of lugs held the screen circuit board on, but having it hang loose is hardly an issue with the picade mounting bracket.

I was even able to use the driver board, button board and the power board for the ccfl from the old TN panel everyone is buying on ebay that I listed in my post above.

Here is the gallery with the pictures labeled as old and new. Pictures were taken minutes apart with the same lighting, display settings and as similar angles as I could manage. The difference is night and day, and for 30 bucks is was a worth while experiment.

New vs Old album

New

New photo by Brandon Hall (Brandito)

Old

New photo by Brandon Hall (Brandito)

Love it. You may be right that the much more expensive, non-CCFL panel is a little overkill for a cab that sits indoors 1 foot away from your face.

Great job!

I wouldn’t say that, I would have gladly bought the original picade 12" screen had I not already bought that crappy ebay model for nearly the same price. This was a good compromise on price and parts I already had. I may actually still get a new driver board that’s been programmed specifically for this display though.

I wonder how this screen compares to yours up close. The added contrasts is what I’m likely missing most with this one.

1 Like

I got your same setup and was wondering about the power supply that you used. I asked the ebay seller and he recommended one that is 12V 5A. Should I get that or would a 12V 1A work just as well? Thanks for the great info.

1 Like

5a seems super overkill. Most LCDs this size will do fine with a 2a PSU, possibly less.

Using the numbers for my panel found here http://www.panelook.com/LTN121XP01-001_Samsung_12.1_LCM_parameter_8277.html

If my math is right, typical usage from a 12v source is less than 500mA, and that’s with ccfl backlighting.

That’s 3.5 watts for the backlight and another 1.2 watts for the lcd or 4.7 watts total. So a 5v 1a source with that 12v adapter cable should just be enough, though 5v 2a would definitely be safer.

Same setup as who?

You’ll need to list what you’re powering, but yes, the 12" screen is usually ~1A and the PiCade/Pi3 is about 2.5A so if you’re powering both 5A is probably the right answer. That’s what I’m running.

Adafruit recommends and sells a 2.5A power supply for the Pi3.

Lastly, there’s an upgraded switched power source that goes up to 2.5 Amps instead of just 2 Amps - allowing your Pi to power even more powerful devices over USB ports.

Note: Our 5V 2A power supply still works great with the Pi 3. For most uses, you don’t need 2.5 amps of power and our 5V2A supply should be sufficient.

I ordered the same screen and board from jopamo’s post. I was asking about the power supply for the 12" screen. I found one at work that is 12V 3A and I think it should work fine with it.

So I got my screen yesterday and everything boots up fine but the video looks shaky and distorted. I verified all connections and everything looks good. I took a video so you guys can see what it looks like. I am no expert so I am clueless on where the issue is.
Even when the pi is not connected to the screen it looks distorted. Could it be the board?

Did you change the display mode in /boot/config.txt?

for the 12" screen at 1024x768 I use

hdmi_group=2
hdmi_mode=16

There’s a link on this page near the bottom with a list of all supported modes.

The issue happens even when the pi is not connected. I can see the distortion on the screen when no video imput is present. I just dont have a way to determine if the problem is the board or the screen.

So you’ve tried connecting it to something like a computer or maybe a blu-ray/dvd player?

It could be a power supply issue, try another if you can.

No but like I told you; even with nothing plugged in you could see the distortion on the “no video input detected screen”. I just tried with another power supply and still no go. I contacted the ebay seller that I got the board from and he wants me to send it back for testing. I just hope it’s not the screen since it would suck to send it back to Japan.