Pull-down resistor problem

[x_zoli]

Hi,

I have to place a pull-down resistor on an FPGA output that is HiZ or weak pull-up during start-up.
The line is quite long and I wonder if I should connect the pull-down to the driver side or to the receiver side of the signal. Any ideeas or docs on this?

 

[osmanpasali]

how long is the route?

 

[x_zoli]

Around 15cm (6 inches).

 

[WhiteSnake]

It is preffered to place the pull down at the receiver side

 

[x_zoli]

Is there a logical explication for this or this is just a lucky tip?

 

[FvM]

With required pull down resistor value, could be e. g. 2.2K, position has effectively no influence on waveforms. I think, there could be more routing space at the receivers end, but you can place in the middle as well.

 

[HardwareArtisan]

Why have to pull down?
If the signal in the trace is static, any position would be ok.
If the sigal will toggle, and your pull down is used for matching line impedence, it usually should be placed at receiver as close as possible.