Hi, I have recently bought a saturn spartan 6 numato board but slightly in problem. I want to interface Saturn Spartan 6 board with an EVM that has 1.8V IO constraint. How can I do it using saturn spartan 6 as VCCIO are all 3.3V Regards.
Hello Mohit, All IOs on Saturn are 3.3V compatible. All banks are 3.3V powered with the exception of the bank used for DDR, which is 1.8V. Unfortunately IOs are not broken out from that bank. The only way to make the IOs 1.8V compatible is to tweak the power supply for the IO banks to make it 1.8V. Unfortunately doing this will need replacing resistors on the board and will void any warranty that may still be in effect. Thanks, Tom
Hi Tom, Even if i replace the resistors, what do i do about the on-board oscillators, E2PROM and VCCAUX? They have to remain 3.3V [oscillators, E2PROM] and 2.5V [VCCAUX] at least. But in the gerber, i found a common plane connecting all of them. Then how do we isolate?
You are right. I overlooked that fact that VCCAUX was powered from the same supply with a few other things. It looks like it is going to quite hard to achieve what you are trying to do. With a multi-layer board like this, cutting traces and connecting jumper wires is almost impossible. Have you looked at of the shelf voltage level translators just in case if they can help ? Thanks, Tom
Thanks for confirmation. Yes, that's the last resort but will make my arrangement with an external EVM very messy.. Anyways, I consider this as a major drawback of this board's usability and should be improved for long run. Regards.
