Overheating defense in Apex20ke

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For now i'm trying very big project on ep20k1000ebc-652-1x and i'm afraid that overheating will damage my FPGA.

Is there any automatic defense in my FPGA that preventing damage by overheating and will shutdown or reset FPGA?

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Nothing unless you add it yourself.

For example, in this Stratix II design:

http://www.ovro.caltech.edu/~dwh/carma_board

The FPGA thermal diodes are monitored using I2C devices, and the alert pins on those devices are used to shut-off power to the FPGAs. Current sensors (INA209s) are first set to a maximum current expected for the design, and are then enabled. If the design uses more-than-expected current, then the power is shut-off.

If you want a robust system, then you'll want to design something similar into your hardware. If you are using pre-existing hardware, then you need to review the hardware schematics to see if there is anything you can use to sense over-temperature and then at least reset the FPGA.

Cheers,

Dave

Thank you for reply!

Unfortunately I'm using alredy existing VME-based board and can solve this problem only by means of FPGA. That's so sad that there is no information on this problem in any altera's datasheet.

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Unfortunately I'm using alredy existing VME-based board and can solve this problem only by means of FPGA. That's so sad that there is no information on this problem in any altera's datasheet.

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If the VME board has no overheating protection, its not a problem of the FPGA, its a problem of the VME board design.

Take a look at the VME board schematic. Do they have a temperature sensor on the board? Does the temperature sensor have alert set-points and does the alert interrupt signal go somewhere useful, eg., to a processor or to the FPGA? If yes, then deal with an over-temperature alarm by disabling the logic that generates all the heat.

Cheers,

Dave

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Uh, I've deal with simple and cruel post-soviet russian board!;)))))) It's hardware are able to work in main purpose, nothing additional.

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In that case, you need to decide how to deal with thermal issues externally.

For example

1) Perform a power analysis of your design. Measure the power used by your design. Measure the temperature of your FPGA.

2) Make sure the FPGA has a heatsink and airflow over that heatsink. If the board is plugged into a VME chassis, then the chassis will provide the airflow. If you are not using it in a chassis, then you should add a fan, eg., a CPU fan. Of course, then you have to locate power for the fan ... so you might need to solder some wires to the board.

3) Bond a temperature sensor to the FPGA package. Monitor the temperature. If you can access a GPIO pin on the FPGA, then route an alert signal from your sensing circuit to the FPGA. If that signal asserts, then disable the logic in your design, eg., use it as a reset for the whole design, or as an enable to the power-hungry logic part of your design.

Cheers,

Dave