Driver boards for IPS screens

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Hello- I’m trying to put together a project with a 5" IPS digital display connected to a Rpi 4. All the assembled screens that I have found are either TFT or have the wrong form factor for our project. So am thinking of trying to find a separate screen and driver board to get the combination needed.

I found a few things that are close but have a couple of questions…

Will this display driver board work with a smaller screen? (connected via LVDS)

or

will this driver board work on IPS screens? or is it just for TFT?

thanks!
Greg

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The driver board has to be compatible with screen, and there are a fair few different interface designs so it’s usually easiest to get a driver and display that are designed to work together.

According to the datasheet, the TFP401 only supports TFT or DSTN panels:

The Pimoroni driver board has been designed specifically to work with the 8 and 10 inch displays from their PiCade kits. Looking at the closeup photos, it looks like it’s based on a Realtek RTD2660H chip:
image

Googling “RTD2660H Datasheet”, I found this:

Which says it can output both TTL and LVDS, so it’s probably technically capable of supporting a good range of displays, but you’d be a bit on your own trying to do it with anything other than the Pimoroni displays.

Adafruit also sell a few driver boards based on the RTD2660H - They’ve got a huge guide here, with a list of all their driver and display combinations:

If Adafruit still sells it, there’s a good chance we could get it in if it’s not already on our site :slight_smile:

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Thanks very much Oliver! super helpful information.
Trawled through the Ada fruit site and it seems that they only have driver boards for TFT in the 5" size (more options in 7" and up) HDMI 4 Pi: 5 Display (no Touch) w/Mini Driver - 800x480 HDMI : ID 1928 : $59.95 : Adafruit Industries, Unique & fun DIY electronics and kits even though it has that RTD2660H
Feel like I might be chasing a unicorn…

thanks again!!

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Hi Greg,

Hmm, what is the form factor you’re after?

Waveshare makes a 5 inch IPS display:
https://www.waveshare.com/5inch-lcd-for-pi.htm

We don’t have it set up with a listing on our site, but we order from Waveshare regularly so we could probably get one in for you.

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Hi Oliver,
I came across that waveshare unit but i think we need the cable from the screen (or control board) to be a HDMI & USB as it is routed through a tight assembly to the Rpi which is about 1metre from the screen. The ribbon cable would be difficult to make work in the assembly and had concerns about the durability and run length.
The Pimroni setup seems perfect except for the question around compatibly with a different screens.

Sorry- i understand that i’m being difficult with our very specific requirements :grimacing:

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Hey Greg,

No worries, makes life interesting! It’s worth making a post over on the Pimoroni Forums about using a different screen with their driver board - just to see what they have to say:

Otherwise, it might be time to consider relaxing your requirement for IPS (TFT displays can be gorgeous - Pimoroni’s Hyperpixel displays are spectacular tbh), or rolling your own DSI - HDMI adapter:

Here’s an older topic about a similar situation:

And some other info I’ve found:
https://forums.raspberrypi.com/viewtopic.php?p=1023780#p1023780

I did find these two displays online made by Elecrow, but I don’t have any experience with them (and they aren’t one of our suppliers) so can’t vouch for their quality at all:

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