Newhaven Display Forum

Newhaven Products => Graphic LCDs => Topic started by: llb on June 18, 2017, 01:21:51 PM

Title: 1.8V IO on NHD-2.4-240320CF-CTXI-F
Post by: llb on June 18, 2017, 01:21:51 PM
Hello,

I want to interface the NHD-2.4-240320CF-CTXI-F with an 1.8V system. The datasheet (http://www.newhavendisplay.com/specs/NHD-2.4-240320CF-CTXI-F.pdf) mentions that IOVDD can be 1.8V, but the logic IO parameters Vih, Vil, Voh and Vol all are specified in terms of VDD (which is 3.3V). Is this a typo in the datasheet (intuitively, I would expect IOVDD to set the IO logic levels, instead of VDD) or can the display in fact only interface with 3.3V logic?

Thank you!
Title: Re: 1.8V IO on NHD-2.4-240320CF-CTXI-F
Post by: Saurabh_B on June 28, 2017, 11:30:55 AM
While the controller for the display (ST7789S) Can work with a 1.8V system, the display will need 3.3V.
Because of this you CAN  use 1.8V on the IOVDD and 1.8V Logic with the data lines (DB0-15, /CS, D/C, /WR, /RD, /RES, IM0)
However you would need to apply 3.3V to the VDD for the LCD circuit. Is it possible for you to supply the +3.3V for the LCD alone?

The logic voltage should be related to the IOVDD, i will make this correction on future spec upgrades.