How to determine Power Enable polarity for IMX477HQ B0249 on Jetson Orin NX CAM0_PWDN?

Nvidia Jetson Cameras
1

Hi everyone, I’m working on a custom carrier design and I’m stuck on the IMX477HQ Camera Module B0249. I can’t figure out the polarity of the Power Enable signal. The Jetson Orin NX SOM has a pin called CAM0_PWDN, but I can’t find anywhere in the docs whether it’s high or low when the camera should actually be enabled. I’m not sure whether to connect the Jetson CAMx_PWDN signal directly to the camera connector’s CAM_IO0 Power Enable pin, or if the signal needs to be inverted. Any guidance would be appreciated.

2

Thanks for posting. Could you share a few more details about your environment? Specifically the camera module model, which SOM/board you’re targeting, and which camera connector pin you’re mapping the Power Enable to. If you have a datasheet link, that would help too.

3

Of course. Here’s what I’m working with:

I’m basically evaluating whether the CAMx_PWDN signal can be connected directly to the CAM_IO0 Power Enable pin, or whether it needs inversion.

4

Thanks, that narrows it down. Could you also share screenshots of the relevant sections from the datasheet? I’d like to see how the Power Enable and the CAM_IO0 pin are described on both sides (camera module and SOM).

5

Here are the images from the documentation I’ve been looking at:

image001.png

image002.png

image003.png

The main thing I’m stuck on is whether the Jetson CAMx_PWDN signal can be connected directly to the camera connector’s CAM_IO0 Power Enable pin, or if I need to invert the signal somewhere in between.

6

Thanks for the screenshots. After reviewing this, the ambiguity is really about the Power Enable signal polarity and the correct wiring between the Jetson CAMx_PWDN signal and the camera connector’s CAM_IO0 Power Enable pin.

The Power Enable signal on the B0249 is high level. That means no inversion is needed. You can connect the Jetson CAMx_PWDN signal directly to the camera connector’s CAM_IO0 Power Enable pin.

7

Okay, that’s good to know. So just to double-check: the camera should be connected directly to the Jetson device, and the Power Enable is active high, so I don’t need to invert CAMx_PWDN? I was a bit worried because the CAM0_PWDN naming made me think the signal might be active low.

8

Correct. To summarize: the Power Enable signal polarity for the IMX477HQ Camera Module B0249 is high level, and the camera should be connected directly to the Jetson device. Connect the Jetson CAMx_PWDN signal straight to the camera connector’s CAM_IO0 Power Enable pin — no inversion of the CAMx_PWDN signal is required.