Noisy txb0104?


I'm using a TXB0104 to interface with my Beagleboard. It's converting
up to 5V.

Put simply, the chip is _incredibly_ sensitive to supply noise, to the
point that I get glitches on outputs even when the input is tied to GND
through a 1.5K resistor positioned as close to the chip as possible.

I have a similar design that's also using the TXB0104, to covert 3.3V to
5V, and it's suffering the same problem. On that system, I've got 200mV
or so of noise on the power supply lines--- not great, but it doesn't
seem to be an intolerable amount except for this chip.

Anyone have any success with the TXB0104, or had a similar problem and
figured out a way to beat it? Simple bypass caps don't seem to do the
trick, even when I have .1uF, .01uF and 33pF caps in parallel at the
chip itself (tantalum, and ceramic disks, respectively).

At the moment, I'm faced with the possibility of having to do a redesign
with some other voltage level conversion strategy. :frowning:

Ideas, anyone? I'd be very grateful!


Why do you need the TXB104? Being bi-directional it wants to detect anything on the input or output and switch quickly. If you only need one direction, I would not use the TXB0104.

The other option might be to try the TXS0104 which requires external pullups which makes it a little slower which could improve the noise issue,. They are drop in replacements for each other. I have not seen this issue before.