Newhaven Display Forum

Newhaven Products => TFTs => Topic started by: dfansler on February 24, 2015, 08:59:11 AM

Title: NHD-7.0-800480EF-20 Controller Board
Post by: dfansler on February 24, 2015, 08:59:11 AM
I recently purchased  NHD-7.0-800480EF-20 Controller Board to go with a 480x800 touch panel from NHD.  A couple of questions about the board that I did not see in the docs:
1.  What voltage does the back light require?
2 . Is there a separate ground for the back light?  Using a low-side driver to control the brightness is much easier than using a high-side driver.
3.  How does one use the Display On Signal?  Is it as simple as 3.3v turns on the display and 0v turns it off?
Kind regards,
david
Title: Re: NHD-7.0-800480EF-20 Controller Board
Post by: Retheesh_M on February 24, 2015, 12:18:25 PM
1. The controller board will supply the required voltage for the backlight.  So you don't need to supply it with a separate power source.

2. There is not.  The board uses a common ground for the backlight and the display.  Pin 3(backlight enable) of J2 can be used to toggle the backlight on/off or modulate the brightness with PWM.

3. Yes, you can turn the display on with 3.3V and off with 0V on Pin 19 (Display On Signal).
Title: Re: NHD-7.0-800480EF-20 Controller Board
Post by: dfansler on February 24, 2015, 03:08:20 PM
Thanks for the quick reply!
David
Title: Re: NHD-7.0-800480EF-20 Controller Board
Post by: dfansler on February 26, 2015, 09:05:04 AM
OK - I have run into another problem with the board.  I am running the controller board from a custom interface board.  The connector on my custom board is a 20 pin bottom contact 1mm pitch yet the controller board has a 22 pin top contact 1mm pitch connector.  The cable is a 20 pin 1mm pitch.  So what connector do you sell do I need to purchase to interface my custom board to the controller board?
Kind regards,
David
Title: Re: NHD-7.0-800480EF-20 Controller Board
Post by: Retheesh_M on February 26, 2015, 10:23:12 AM
Even though the controller board has 22 pads the FFC connector has 20 pins only.  The last two pads on the controller board are not connected nor are they required.  You should be able to use the 20-pin flex cable to connect to your custom interface board.  Please refer to page 4 on the datasheet for more information. 
Title: Re: NHD-7.0-800480EF-20 Controller Board
Post by: dfansler on February 26, 2015, 11:04:50 AM
I realize I can use the 20 pin flex cable and that the connector on the NHD controller is 22 pin - my question is what NHD connector do I need on my custom board to interface to the 20 pin cable?
Thanks,
David
Title: Re: NHD-7.0-800480EF-20 Controller Board
Post by: Retheesh_M on February 26, 2015, 11:49:49 AM
The connector on the NHD controller board is in fact 20 pin, 1mm.  You can take a look at the note on the bottom of page 4 of the controller board specification sheet.  Since your custom board has the same number of pins and same pitch, you should be able to use a 20-pin FFC connector.

So you can either keep the same connector that you have currently installed on your custom interface board and use a cable with opposite side contacts on both ends or change your 20 pin connector to a top contact and use a cable with contacts on the same side on both ends.