Cyclone 10 GX 3V IO Voltage

[JLee25]

Hi community,

I have a new project based on C10 GX and I am debugging the IO problem.

The device is 10GX220YF672, the IO bank 2L was design to interface 3V IO.

I download a counter design to verify the operation, it will toggle every 200 ms.

From waveform, the high level is only 0.9V instead of 3V that I am expected.

What would be the problem?

If my external devices boot earlier than FPGA, will it cause this issue?

Please help!

BRs,

Johnson

[YuanLi_S_Intel]

Hi Johnson Lee,

Just want to check, have you set the IO Standard of Bank 2L to 3.0V?

It is not a problem for an external devices that boot earlier than FPGA if you obey the pin state as shown in the user guide:

https://www.intel.com/content/dam/www/programmable/us/en/pdfs/literature/hb/cyclone-10/c10gx-51003.pdf (Page 273).

For example, LVDS I/O banks need to be tristated (Setting in Quartus) while power up and vice versa.

Thank You.

[JLee25]

Hi YL,

Thank you for reply.

Yes, I did set the IO standard to 3.0V.

Attached is the qar file for your reference.

I test 2 boards with this configuration.

Both show the same status,

before config, gpio_0 is 3V, led_0 is 0.7V. After config, gpio_0 switch between 3V/ 0 V. led_0 is 0.9V/ 0V.

Regards,

Johnson

[JLee25]

Hi YT,

I just found the clock was not operated properly, amplitude is small..

I will check it and see if this is the root cause!

Thank you!

Regards,

Johnson

[JLee25]

Hi YT,

I have a question on the reference file.

From the table below, it means the external IO pin should be in Tristate during FPGA boot up ?

If above rule can’t be followed, what will happen to the device?

And what should I do to prevent this?

Boot external devices later than FPGA ?

Please comment.

Thank you!

Best Regards,

Johnson Lee

[YuanLi_S_Intel]

Hi Johnson Lee,

No tri-stated is needed from external pin. During FPGA power up, the pin itself will tri-state for used pin. Meanwhile for unused pin, you will need to do some setting in Quartus to enable tri-stating.

To do so, go to "Assignments" -> "Device" -> "Device and pin info" -> "Unused pin" -> "As input tri-stated with weak pull up"

Thank You