Beagleboard Level Shifter

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I've recently order a Beagleboard-xM. While I'm waiting for it to be shipped out(its on backorder for a couple of weeks) I'm trying to find level shifter to work with it. The Beagleboard runs at 1.8V and I need to interface it with my AVRs using I2C running at 5V and a GPS use UART running at 3.3V. I have looked but the only ones I can find have funky packages that I don't want to solder. So, I was wondering if anyone knows of any good level shifters with DIP packages that I might be able to use?

p.s. I also don't mind making my own level shifter from scratch if anyone has a circuit that could work.

Sorry if there are spelling errors or the question sound a bit spoon feedy; I'm posting this at 3:34 am.

Life Is Like A Bucket Of Chicken.

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I ran into this app note recently, describing a two-MOSFET I2C level shifter. Perhaps it will be of some help.

Otherwise, it might be a good time to start playing with surface mount packages. They really aren't too hard to work with, and they'll open up your options significantly.

Michael

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Sorry it took so long for a reply.

I was wondering if you think two connected inverters, like at the bottum of this page: http://mbonnin.net/39-electronics/, and a voltage divder in parallel with that, would be a sufficient level shifter for the Beagleboard for GPIO, UART, and I2C?

Future Thanks,

Life Is Like A Bucket Of Chicken.

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No, it won't work because I2C is bidirectional. It won't also work because there is no base resistor, and the base resustor and collector resistor could make the signals rise very slowly.

For I2C you need a chip that can handle it or just the FET transfer gate solution.

Regular logic chips can be used for unidirectional level shifting, like some 74LVC245 buffers or the like can eat 5V and output 3.3V with 3.3V supply. There must be some chips that work down to 1.8V.