NHD-0216CW-AY3 VDD and REGVDD pin && SPI example

[heijinzhai]

Hi experts,

I'm using NHD-0216CW-AY3 in our product, the spi interface is in used, can you give me some comments on these two questions?

1) pin REGVDD, VDD is the power supply for OLED and logic, by "logic" is it the control interface, which is SPI interface in my design? I'm using 3.3V now, is that mean the io standard of al control signals is 3.3V LVCMOS?

2) pin REGVDD, it is "Internal 5V I/O Regulator select signal" in datasheet, the internal regulator is used for what? In my design, I have connected VDD with 3.3V, does it mean I need to connect it with GND for the "2.8V operation"

3) I found an example code for SPI interface in the link below, which is used for NHD-0216KZW, can it also be used by NHD-0216CW-AY3 in my product?
http://www.newhavendisplay.com/app_notes.html


Thanks
Chris

[Saurabh_B]

Hello,

I am not sure if i understand your first question.
However with the logic being set at 3.3V, you will want to make sure your SPI counts 3.3V as high, and GND as low.

If you are using this display in 3.3V you will want to ground RegVDD, and in the software you will want to disable the regulator.
the KGZ code will not work for this display.

You can find the example code for this display here: https://github.com/NewhavenDisplay/NHD_US2066

[heijinzhai]

Hi Saurabh_B

Thanks for your quick response. It seems when VDD is 3.3V, RegVDD should be connected with GND.

RegVDD is an internal 5V I/O regulator select signal, can you tell me what is the "internal 5V I/O regulator" used for?

Regards
Chris

[Saurabh_B]

The OLED typically runs off 2.8-3.3V, When using 5V you would enable it so that the OLED will regulate the voltage down to the 2.8-3.3V levels.