Operative temperature range

VPU temperature range

The visual processing unit - VPU (MyriadX) - is rated for industrial use and has operating temperature of -40°C to 105°C (as seen here), while other components have a higher temperature range.

General use case

Max temperature

In the general use case at a 25°C ambient, the chip running at full power (i.e. worst-case heat generation) resides at around 70°C maximum, which sets the thermal margin to a minimum of 35°C.

Since devices generate about 45°C in worst-case, this means the maximum ambient temperature should theoretically be 60°C (105°C-45°C=60°C).

Min temperature

While an OAK camera would work below 0°C, a valid concern here is the condensation on the components with cycling the temperature - if the device isn’t waterproof. Worst case would be turning the cameras on and completely off several times week or even a day. This would cause condensation on the components and because of that, the stress on components would be bigger. Solution would be to spray PCBAs with a conformal coating to protect the components against humidity.

Pro versions (OAK-D Pro, OAK-D Pro PoE) have on-board IR laser dot projector that has an operating temperature range of 10°C - 60°C (abolute limit 0°C - 80°C). If you would like to use Pro devices below 0°C, we would suggest to first run the device (without projector) for a few minutes so the device heats up, which would also heat up the laser projector, hopefully above 10°C.

Command used for testing

We have tested thermals of our devices with max load, and you can achieve that by using the depthai_demo: python3 depthai_demo.py -sub -lrc -rgbr 2160 --report cpu -enc color -encout /dev/null

This command has the maximum power consumption, therefore the devices have the highest heat output.

Note the framerate of the RGB camera is set to 30 (-rgbf 30). If it would be set any higher, it would be bottlenecked by the neural network.

Results of our tests

All devices were tested in an ambient temperature of 18°C to 20°C.

Test on the OAK-D-PCBA - rear thermal plate with black anodizing and Laird HD320 TIM:

  • Heatsink max temperature: 43°C

  • Die max temperature: 60°C

../../_images/OAK-D-PCBA_heatsink.jpeg

Test on the megaAI with the Tianmai 6.5W/K TIM for both the front heatsink and the MX. TMA-6518 (0.5mm) for the MX and the TMA-6500 (2mm) for the front were used. This test was with the BW machined heatsink.

  • Heatsink max temperature: 61°C

  • Die max temperature: 73°C

../../_images/megaAI_heatsink.jpeg

Tests for OAK-1:

  1. 6535 back TIM only:

  • Die max temperature: 78°C

  • Rear heatsink max temperature: 62°C

  • Front heatsink max temperature: 60°C

  1. 6510 front + 6535 back TIM:

  • Die max temperature: 70°C

  • Rear heatsink max temperature: 59°C

  • Front heatsink max temperature: 60°C

Test with T1 OAK-1 sample:

  • Rear heatsink max temperature: 61°C

  • Front heatsink max temperature: 63°C

  • Die max temperature: 73°C

../../_images/OAK-1_heatsink.jpeg

We have also tested the devices at the lowest ambient temperature of -25.1°C and they worked as expected.

Got questions?

We’re always happy to help with code or other questions you might have.