Whats the best IOB choice for databus using Spartan IIe?

[jonatan]

lvttl in ise ucf

Please,

I am trying to acquire a databus (12 bits) from an A/D converter
(with sample rate configured at 50MHz) using SPARTAN IIe and IO buffer configured as LVTTL (SLEW) in the input pins of UCF file (ISE 6.1i).

Is the LVTTL (SLEW) IOB fast enough to be activated by the databus
at 50Mhz ?

Or I should replace the LVTTL IOB type for another one available...

In other hands, what is the best IOB choice for this case?

Thanks in advance...

 

[delay]

Re: LVTTL in Spartan IIE?

A fundamental question is what is the voltage level presented by the A/D on the bus? Spartan IIe is fast enough to sample data at high rate such as 50MHz but the I/O level configured in UCF must match the external device.

 

[jonatan]

Re: LVTTL in Spartan IIE?

Thanks DELAY,

I am employng LVTTL because the output data from A/D board is 5V , once it is provided through the buffer SN74ABT16244A.

LVTTL is one of the available IOBs compatible with this level according
with SPARTAN-IIE datasheet.

 

[power-twq]

Re: LVTTL in Spartan IIE?

Yes, LVTTL is capable of signaling with 50MHZ.

best regards

Please,

I am trying to acquire a databus (12 bits) from an A/D converter
(with sample rate configured at 50MHz) using SPARTAN IIe and IO buffer configured as LVTTL (SLEW) in the input pins of UCF file (ISE 6.1i).

Is the LVTTL (SLEW) IOB fast enough to be activated by the databus
at 50Mhz ?

Or I should replace the LVTTL IOB type for another one available...

In other hands, what is the best IOB choice for this case?

Thanks in advance...