Useful thermal Gateworks wiki pages

• Very Resourceful Thermal Management Page
• Dynamic Voltage and Frequency Scaling of the Processor
• Venice Power Consumption
• FAQ - Why is my board running hot?
• ​Gateworks Shop - Heatsinks

Thermal Ratings

Gateworks pre-installs a heatsink on the CPU for all Venice boards. This heatsink provides basic cooling for the board during development but customers need to design their own thermal solution based on their particular enclosure, environment and operating conditions.

The 1600MHz IMX8MM Industrial Temp SoC used for Venice is rated at:

• Max: 105C Tj (Junction Temp)
• Min: -40C Tj (Junction Temp)

The thermal resistances for the packages assuming natural convection is:

• RθJC (junction to case) = 4°C/W
• RθJB (junction to board) = 7.8°C/W
• RθJA (junction to ambient) varies per baseboard but is expected to be about 20°C/W

Venice Temperature Readings

Venice has the ability to measure the board temperature and CPU temperature.

Both values are important, but the CPU will be the hottest component and thus should be watched closely.

CPU Temperature

The IMX8MM internal CPU junction temperature can be read via Linux:

cat /sys/class/thermal/thermal_zone0/temp

The value show is C*1000 and the position of the thermal sensor varies per baseboard but is typically near the power supply.

Board Temperature

The board temperature can be measured through the GSC:

cat /sys/class/hwmon/hwmon0/temp1_input

The value show is degress C*1000 and the position of the thermal sensor varies per baseboard but is typically near the power supply.

Venice Heatsinks

The Venice System On Module (SoM) has a 20x20x10mm (LxWxH) aluminum heatsink for passive thermal dissipation.

Some boards also have a 4-pin Fan controller connector suitable for driving a 5V fan via PWM with Tachometer feedback if active cooling is needed for the system. The fan is automatically controlled through the fan set points as defined here