OpenMV Camera Module Extension Cable kills image sensors

Hello,

I purchased several Camera Module Extension Cables to use with my OpenMV H7 cam, and the cables have killed multiple image sensors. Before using the extension cable, the image sensor works when attached directly to the H7 board. After disconnecting power, detaching the image sensor from the main H7 board and attaching the extension cable, image sensor, and H7 board in the orientation shown on the product page, the camera no longer shows up when using the IDE. The chip on the main board gets very hot.

After this, with the extension cable and image sensor detached from the board, the board cannot connect to the IDE. It rapidly flashes all the indicator LEDs, which to my understanding indicates a “hard fault” as discussed in this forum post. I have tried wiping updating the camera with no change in status.

I’m frustrated that these cables have killed two image sensors and a board. I a different cable was used each time. What’s going on here?

Hi Tim,

We just received a new batch of cables from our supplier. I assumed they have been tested. However, can you tell me where you ordered them from and when?

To note, while the camera sensor may not work with the cable but it should continue to work when plugged back into the camera. I haven’t exactly explored trying to connect it incorrectly however. But, when we initially designed these cables we found them safe. The sensor and main board shouldn’t be permanently damaged if the connection is backwards.

-Kwabena

Kwabena,

Thanks for your quick reply; I appreciate your response. I purchased the cables on October 24, 2022 directly from the OpenMV website. The shipment tracking indicates that they started their journey in Shenzhen, China.

After having the sensor connected with the extension cable, I’ve tried plugging it directly back onto the main board, and the IDE can’t detect the sensor. I’ve tried reattaching the fried sensors to multiple known working boards. I’m fairly confident that the damage to the sensor is permanent, and one of my boards is also not working.

Are you willing to share the pinout of the image sensor/main board and the pinout pattern of the cable?

Hi, the pinout of the camera and bemoan board are online. The cable is just a direct connection per pin. It has no schematic like the main board or the camera.

Okay, please let me know the order number and I’ll check with our cable manufacturer.

As for the camera unit that’s busted. Where was that bought from?

Kwabena,

My OpenMV order number for the extender cables was: 7127.

I bought the camera from Digikey in November 2022. It’s an H7 R1.

Kwabena,

Thank you for your support. I found the image sensor pinout online, used a multimeter to verify the traces of the extender cable, and used the extender cable to connect the image sensor and the main board in the orientation that I predicted would provide appropriate connection; this time, the image sensor worked! The IDE found the sensor, and the frame buffer displayed the image. It’s worth noting, however, that this orientation with the successful image transfer does not match the orientation shown in the official product image; my successful orientation has one connection rotated 180 deg from what is shown in the product image. When I tried the orientation shown in the product image, my sensor died. This may cause issues for users.

Upon viewing the pinout diagram, I did identify what I believe was the cause of my image sensors being killed. If the extension cable connection is rotated 180 deg, either on the image sensor side or the camera board side, pins get connected that should not be. I believe the issue is that Pin 10 (VCC) and Pin 27 (GND) swap places. This likely pushed power in the wrong direction/to the wrong location on the image sensor and caused damage.

where is this image with the wrong connection?
hopefully when i tried mine extention cables worked just fine without trying to swap the connector 180 degrees though.

The diagram shows what each pin should be connected to; the VCC on the camera’s board should go to the VCC pin on the image sensor. If one of the cable connections is rotated 180 deg, the expected connections are no longer made, and any pins that get connected incorrectly could cause trouble.

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Huh, the picture should be right. I haven’t changed this in a while.

So, everything is working again?

In the appropriate connection orientations, yes, things work fine. I’ll need to make sure that I avoid the destructive orientations, though.

I know this is 8 months later, but it may help someone else.

Tim is correct. Image #5 on the Extension Cable page shows the Camera the wrong way. Fortunately, I worked it out myself before referring to the image, but thought I should rather check online. Luckily, I connected it the right way around.

Just another point of note: If you have the cable connected the right way around and everything works, you can also rotate both items (OpenMV board and Camera) at either end of the cable by 180°. Thus there are two options when using the extension cable. I have tested it to work with both options, but please be careful.

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Okay, I’ll get that fixed.

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