GPIO can't hold 3.3V when used as trigger in relays?

I’m trying to trigger a relay with the GPIO pins on the Jetson Xavier NX Development Board.

Here is the relay I’m using. I’ve used this with the Raspberry Pi, Arduino, and Odroid (Hardkernel). It’s robust for AC applications with small 3.3V triggers.

I’m using the python library, which, when unloaded, seems to do what I want (3.3V out) on pins 11 or 12 (BOARD). I can’t get 3.3V on pins 31 or 33 for reason, but that’s a different issue. I haven’t tried any other pins.

It appears, however, when I plug it into the relay and trigger HIGH, the voltage drops to 1.7-1.8V. I’m just looking to understand what’s happening? It’s not the relay as I’ve swapped in a few different ones and changed out the connectors.

Funny enough, I can use a cheap 5V relay to trigger 5V to the IOT relay from above using the 5V pin on the Jetson. I’m not super happy using two relays in series though.

Surely I’m doing something wrong or maybe I’ve broken something?

Please check below 40-pin header docs first:

https://developer.nvidia.com/jetson-nano-developer-kit-40-pin-expansion-header-gpio-usage-considerations-applications-note

That file is 403’d. Also, does it apply to the Xavier (it has Nano in the title).

It can be for Xavier too. You can find the files in DLC: Jetson Download Center | NVIDIA Developer