EVE3x-70A electrical connection documentation

[johnschimandle]

I'm a newbie on this forum but a consultant with lots of experience in embedded system design. I'm looking for something super simple, which I'm sure exists, but I just can't seem to find it on the Matrix Orbital Web Site.

I'm designing an interface cable from my custom embedded system PCB to the EVE3x-70A display. I need to know where the connectors are located and the pin out for each connector. This is pretty standard information.

- I downloaded the mechanical drawing for the display but no connector locations
- The description for the display says it uses a "Standard 20 pin connector". Never heard of such a thing. Googled it and all I got was JTAG connectors. Confused here.
- There is no user manual for the display that I can see which describes how to electrically connect the display to your embedded system board. I know the digital signaling level is 3.3V, I've have the 5-15V power option.
- I read the post on the mirrored pin out and I understand that issue with flat cables. Not sure if it applies to this particular display.

I could use some help getting the correct documents for the EVE3x-70A display that shows the location of the connectors, the pin out and signal descriptions.

[johnschimandle]

I took a closer look at the Bridgetek BT-815 datasheet and was able to get the digital signal levels from there. I'm assuming it is a pass thru from the EVE3x-70A interface board header to the BT-815 pins. There was a sample circuit documented in the datasheet but it shows an 8x2 16 pin header so I'm guessing that is not the "standard 20 pin header". The BT-815 datasheet sample circuit shows a 4.7K pull up on the INT# signal that originates from the BT-815. Is that resistor included on the EVE3x-70A interface board or do I need to provide that? I know there has been some resistance against releasing schematics for the Matrix Orbital interface boards and I get it, Proprietary information. Just need a few answers and hopefully there is already a document.

[johnschimandle]

now I have the EVE3x-70A on my bench with the 5-15V power option. I'm using a 15V power supply. I see the 20 pin connector with reference designator J6. The connector signals are labeled but somewhat misleading.

I'm not sure where the ~RST signal goes. I had assumed it would connect to pin 12 (PD_N) on the BT815 so I would have control of the power down signal on the BT815. This is a critical signal for controlling the chip.

All the VCC 20 pin header pins have the input voltage of 15V on them. That was not anticipated. I assumed that the VCC pin next to all the SPI pins would have the 3.3V VCC for the BT815. I need to get access to the 3.3V for my level shifter since the my processor board uses 5V logic. I can see 3.3V on C10 on the U2 side. Why doesn't this go to a connector?

need help on J5 pinout.

[johnschimandle]

talked with support and they recommended the pin out is documented in the EVE3x-43A display documents tab by downloading the user manual EVE3x-43-Manual.pdf. The EVE3x display is found at https://www.matrixorbital.com/eve3x-43a-ips. Section 4.1 documents the pin out of the 20 pin FFC flat cable and support says the pin out of the 2x10 header is the same pin out. There are a few issues with this pin out. Pin 1 is supposed to be 3.3V logic voltage but I measure 15V from the power input pin. Pin 8 is documented to go the BT81x PD_N pin but according to support there is some intervening logic. It eventually get to the BT81x part but you cannot use this pin to monitor the PD_N pin on the BT81x.

I have modified the PCB and cut the trace to J6.17 to get an open pin. Then I soldered a jumper wire from C10, U2 side, to J6.17. This brings the 3.3V logic supply to J6.17 for use with my level shifter. This will get me through development but not sure what the long term solution will be.

I have requested better documentation on J6 signals for the board with 5-15v power option. Waiting for documentation.

[johnschimandle]

After receiving documentation, it is possible to route the 3.3V to J6.1 by moving R11 to R14. No need to cut the trace and use the mod wire. Just might be a manufacturing BOM issue on the 5-15V power input option.

[Raquel]

Hi John,

I am glad you have figured things out.
If you need to have the EVE3x-70A customized for your needs, we can setup a custom for you (such that certain resistors are populated).

Thank you,
Raquel