cmoda7 CMOD A7-35T

[Luigi88]

Hello,

Does anyone know what is the maximum current consumption on this board? 

I'm creating a PCB with the XC7A35T FPGA but I can't find any specification except the LTC3569 maximum output current.

Thank you.

 

[Luigi88]

No one knows?

[dpaul]

Welcome to the world of technical forums!

When no one answers, it might also mean that finding the answer for the Q is uninteresting or it takes too much effort to find out the right answer (digging in to datasheets, cross-comparing, etc). :-)

[Viktor Nikolov]

@Luigi88, I'm sure you understand that the current consumption of a PCB with an FPGA depends on the peripherals used, i.e. how much current you draw from the FPGA pins. 

The designer of CMOD A7 selected the buck converter with max. 600 mA into the 3.3 V power rails. I guess it's a plenty of current for normal applications.

Theoretically, the XC7A35T I/O pins can draw more than 600 mA. I'm judging based on this support post and Table 8 in the datasheet DS181. But it depends on your application and heating/cooling considerations.

[Luigi88]

Hello, @Viktor Nikolov

 I'm migrating a Verilog project from the Altera De0 nano to the Xilinx XC7A35T. With the Altera FPGA, I measured 250mA total consumption. So I'm guessing it will be roughly identical. However, using XPE with 10 lvcmos 3.3 and 16mA I/O resulted in approximately 500mA. Could it be correct?

Thanks!

[Viktor Nikolov]

I'm sorry, but I'm not able to advise on XC7A35T consumption vs. Altera. 🙁 As usual, the real measurement is the "king".

[Luigi88]

Good day @Viktor Nikolov,

I implemeted my Verilog project on the CMOD A7 board and I generated the bitstream. This is the report power (setting 400pF output load , no heat sink, 30°C ambient temperature, maximum process, toggle at 100% also in the default activity). 

The maximum current is under 900 mA, so I'm confident that it will be under 1 A in the final pcb. 

Is this correct?

Thank you!

 

Ps. in the confidence level only I/O activity is Medium.

 

Edited May 28 by Luigi88

[Viktor Nikolov]

I'm sorry, but I'm not knowledgeable enough on this topic to pose as an authority.

Perhaps AMD Xilinx Support Forum POWER & POWER TOOLS is a better place for this question.