Automatic I/O voltage sensing (as XILINX ParallelCable IV)

[Amontec Team, Laurent Gau]

Hi all,

Sorry to ask about analog question, but it 's relative to FPGA too.

Do you know a schematic to do 'Automatic I/O voltage sensing' as XILINX
does with the ParallelCable IV.

I am designing a new JTAG interface (USB), and I want to be able to
drive correctly the target JTAG signals (3.3V, 2.5V, 1.8V, 1.2V).

Are there any lvttl level shifter device to do this work?

Thanks for your advice.

Laurent Gauch
www.amontec.com

 

[Peter Wallace]

On Wed, 01 Oct 2003 06:21:04 -0700, Amontec Team, Laurent Gauch wrote:

Hi all,

Sorry to ask about analog question, but it 's relative to FPGA too.

Do you know a schematic to do 'Automatic I/O voltage sensing' as XILINX
does with the ParallelCable IV.

I am designing a new JTAG interface (USB), and I want to be able to
drive correctly the target JTAG signals (3.3V, 2.5V, 1.8V, 1.2V).

Are there any lvttl level shifter device to do this work?

Thanks for your advice.

Laurent Gauch
www.amontec.com

On the recieve side, probably the best thing is to use a LVDS pair with
one side for your input (maybe divided by 2 with low value resistors to be able
to get the 3.3V range) and the other side biased with a PWM generated voltage
to set the input threshold. The common mode range and speed of the Xilinx LVDS
inputs is impressive...

Peter Wallace




Peter Wallace

 

[Stephan Buchholz]

Laurent

The Philps Semiconductor GTL2010 10-bit bi-directional low voltage
translator might help
Steve Buchholz
"Amontec Team, Laurent Gauch" <laurent.gauch@amontecDELETEALLCAPS.com> wrote
in message news:3f7ac650$1@news.vsnet.ch...

Hi all,

Sorry to ask about analog question, but it 's relative to FPGA too.

Do you know a schematic to do 'Automatic I/O voltage sensing' as XILINX
does with the ParallelCable IV.

I am designing a new JTAG interface (USB), and I want to be able to
drive correctly the target JTAG signals (3.3V, 2.5V, 1.8V, 1.2V).

Are there any lvttl level shifter device to do this work?

Thanks for your advice.

Laurent Gauch
www.amontec.com

 

[Amontec Team, Laurent Gau]

Stephan Buchholz wrote:

Laurent

The Philps Semiconductor GTL2010 10-bit bi-directional low voltage
translator might help
Steve Buchholz
"Amontec Team, Laurent Gauch" <laurent.gauch@amontecDELETEALLCAPS.com> wrote
in message news:3f7ac650$1@news.vsnet.ch...

Hi all,

Sorry to ask about analog question, but it 's relative to FPGA too.

Do you know a schematic to do 'Automatic I/O voltage sensing' as XILINX
does with the ParallelCable IV.

I am designing a new JTAG interface (USB), and I want to be able to
drive correctly the target JTAG signals (3.3V, 2.5V, 1.8V, 1.2V).

Are there any lvttl level shifter device to do this work?

Thanks for your advice.

Laurent Gauch
www.amontec.com

Thanks,

You confirm what I'm thinking to use.

For your info, GTL2010 is corresponding with TVC family from Texas.
I will try with this !

Laurent
-> www.amontec.com