Urgent: Regarding Expansion Header in Beagle Board


I am using Rev. B module. I am currently working on a project of
Autonomous Navigation, where Beagle Board is our main OBC(On Board
Computer). But, the main problem is that the expansion header output
voltage level is 1.8V whereas most of our peripherals work on 5V logic

Is there any solution available, or am I supposed to go for a level
shifter IC (If so please suggest me the required chip which does this
level conversion) or it would be better is some other reliable
solution is possible.

Please, let me know it as early as possible.

You will most definitely require a level shifter. The type of level shifter depends on how the signals are used (Mode) and direction (In, out, bi). If you would like some assistance, then you will need to provide more information on what pins you are using and how you are using them.


TXB0108 (http://focus.ti.com/docs/prod/folders/print/txb0108.html)
could be a good choice. Guys, please correct me if there is any issue
with this chip concerning BB.


It is fine but it cannot drive large capacitve loads at high speed if used in a bi-directioanl moden. There should be no issues in a single direction. This is the device, smaller version, that is used on the Beagle today.


But, it would be nice if you can suggest me some level shifter.

Again, I need to know how you plan to use it. If it is in one direction, I would use a split rail buffer that has one rail at 1.8V and the other rail at whatever voltage you need. If you need bi-directional, then the TSB0108 is fine as long as the traces are short and the speed is not too high. If you want more details, then I need more details from you.


Thnx a lot Kunal.

I used a TXS0102DCTR to translate levels on the I2C channel, and then
used a I2C IO expander to be able to drive loads at 5v 100ma.

This is a great way to expand the I2C. But, this goes back to my original question. What pins and functions are being used? Until that information is provided, we will all just be guessing as to what the requirements are.