New Himax HX8347-A TFT and some confusion

Using Arduino Displays
1

Hello,

I just recieved a new display. The description on ebay says this about it:

Specifications:
3.2" inch TFT LCD module integrated a Himax HX8347-A TFT LCD controller and ADS7843 compatible touch screen controller as well as a SD card cage. It is suitable for embedded systems which require display high quality colorful image or video with interactive control and storage purpose. The Module interfaces to microcontrollers via a 2*20 Pin 2.54mm dual row pin header interface , can easily be connected to any microcontroller or FPGA and DSPs.

-- HX8347-A 240RGBx320 a-Si 262K color TFT controller
-- ADS7843 compatible touch panel controller
-- Standard SD card cage
-- Support 16 bit RGB565 format , can connect any 16 bit data bus
-- Onboard 3.3V regulator require a single 5V supply
-- 3.3V I/O voltage level tolerance
-- Module Size : 94(L) * 64 (W)* 14mm(h) including connector

I'm confused about the Line: "Onboard 3.3V regulator require a single 5V supply" Does this mean that it's a 3.3v device or a 5v? I'm guessing that it's a 3V device because of the line: "3.3V I/O voltage level tolerance"

Any help is greatly appreciated!

Loren

2

From the text you posted I would take it to mean the device needs a 5V supply and it has it's own 3.3V regulator to drop the voltage down. The "3.3V I/O voltage level tolerance" implies either the device needs 3.3V level for the I/O pins and connecting to 5V may/will cause damage or 3.3V I/O will work okay.
Do you have a link?

3

Here is a link to the item: http://www.ebay.com/itm/290794763628?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1497.l2649

The other thing that leads me to believe that it's a 3.3V is that pin2 lists 3.3 by it. In fact after looking at the ebay page again it says 3v right at the top.

Thoughts?

4

The site does not really help but a quick look at a datasheet for the HX8247-A and it looks like the data lines are only 3.3V tolerant

Logic voltage (IOVCC): 1.65 ~ 3.3V
Driver power supply (VCI): 2.3 ~ 3.3V

and the power supply is 3.3V

5

Cool, thanks for the help!

6

Would a voltage divider with a 1k and a 2.2k resistors work to test this?

7

also would it be possible for me to run this at 4 or 8 bit instead of 16 for testing purposes?

8

Loren:
Would a voltage divider with a 1k and a 2.2k resistors work to test this?

That would push the voltage out of recommended range (assuming the 2.2K is to ground). Maybe better to use something like 1K & 1.5K that should give about 3V. Maybe other on here have different ideas.

also would it be possible for me to run this at 4 or 8 bit instead of 16 for testing purposes?

Datasheet shows you can only use 8, 16 or 18 bit data bus, alas no 4 bit bus mode.