Friday, July 19, 2013

NHD-C12832 Breakout

This is a breakout board for NewHaven's NHD-C12832 graphic display, a 128 x 32 pixels display with an SPI interface. I like this display mainly because it's cheap (about $11) I think it was the cheapest one I could find with this resolution, and it also looks great. However, it has an unusual package (tight pitch pins and four holes, two for the backlight and two for the screen) so I had to spend some time working on the footprint and PCB, but the end result was good.

I placed all components on the backside of the PCB to keep it as small as possible, the board has a 3.3v 150mA LDO regulator (the display operates from 2.6v to 3.3v) and a level shifter (74VHC541) to convert the logic signals to the operating voltage, so it's compatible with 5.0v logic and can be powered from 3.3v up to the maximum rating of the voltage regulator. The backlight is connected to the regulator via a MOSFET (it draws 45mA maximum) which can be controlled with PWM. The display has an SPI interface and draws about 0.45mA maximum.
The display controller is supported by u8glib, so I wrote small Arduino sketch to test drawing a bitmap,  to generate the bitmap, I used gimp to convert the image to black and white (1-bit) and then exported it to hex (save as .xbm) and then included that as a header in the sketch...



Sources:
The repository includes the Eagle files and the Arduino sketch.

hg clone https://code.google.com/p/nhd-c12832-breakout

5 comments:

  1. so... where do you get those 11$ modules from?

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  2. Looks like these use the ST7565 controller. You might like to check out my page at: http://edeca.net/wp/electronics/the-st7565-display-controller/

    They are very nice displays.

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    Replies
    1. that's right, it's also supported by u8glib, so it worked out of the box, nice work though :)

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