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VADJ mismatch between FMC126(2.5V required) and VC707(output 1.8V)

[font=arial, sans-serif][size=14px]Dear,[/size][/font]
[size=0pt][font=Arial]On the developement board VC707, XC7VX485T-2FFG1761 has no 2.5V HR I/O or 3.3V HR I/O, instead, it has only 1.8V HR I/Os.[/font][/size]
[size=0pt][font=Arial]VADJ and the level of VCCO is 1.8V at the most on board VC707, which can cause a problem when FMC126 mounting on the FMC1 interface of board VC707. [/font][/size]
[size=0pt][font=Arial]There is only one bank of XC7VX485T-2FFG1761 powered by FMC1_VIO_B_M2C, which is strangely supplied by FMC126.[/font][/size]
[size=0pt][font=Arial] In theory, FMC1_VIO_B_M2C should be 1.8V, but unfortunately, it is only 1.67V, which can not reach the minimum requirement of 1.71V.[/font][/size]
[size=0pt][font=Arial]Maybe the input(VADJ from VC707) to the LDO  in FMC126 is just 1.8V [/font][/size][font=Arial][size=14px] [/size][/font][font=Arial][/size][size=0pt], so the output cannot be up to 1.8V. And in ML605, the VADJ is 2.5V, the [/size][/font][font=Arial][/size][size=14px]FMC_VIO_B_M2C is 1.8V and everything is OK.[/size][/font]
[/size][size=0pt][font=Arial] As a result, FMC126 can not transmit data to XC7VX485T-2FFG1761, and we can not get A/D data using chipscope. [/font][/size][size=14px]
[font=arial, sans-serif][/size][size=14px]In a word, FMC126 requires that the VADJ form VC707 is 2.5V, but VC707 just outputs 1.8V.[/size][size=14px][/font]
[/size][size=0pt][font=Arial]Why does this happen? Please do me a favor and give me a solution.[/font][/size][size=14px]

[font=Verdana]Dear Sir,[/font]

You need a new FMC126 to be used on VC707. The newer FMC12xs are supporting VAdj down to 1.3V.

The boards you are trying to use were shipped in January 2011 at a time VC707 was not even existing.

The only solution is to purchase new boards or to stick with ML605.

Best Regards,

I am so sorry that I don't have too much time. Physically, Could you give me a solution, such as using wires to give another power supply to FMC1_VIO_B_M2C(1.8V)

Dear Sir,

I am sorry but I don't have any solution to get your 4 years old board on a last year's carrier board.

Use ML605 or purchase a FMC126 r2 hardware.

Best Regards,
This topic is being closed because the issue is considered as resolved by 4DSP. Feel free to create a new topic for any further inquiries.