TXB0104: TXB0104 OUTPUT signal shake problem

Dear TI members:

When I use TXB0104 in SPI(3.3V-1.5V)，and put a 2k pull-dow resistor in IO，the Voh become lower and shake。

I found the reason that TXB0104 can't diver high load and it will reduce the level of the output in your datasheet.

But I still want to know why the output signal repeatedly rise and fall.

Do you have some  idea about that? Thanks.

Amy Luo：

您好，

您是A端口接1.5V，B端口接3.3V吗？请确认下，因为A 端口支持 1.2V 至 3.6V 的电压，B 端口支持 1.65V 至 5.5V 的电压 ，需满足 VCCA ≤ VCCB

另外，上拉或下拉电阻值要大于50KΩ，估计是您使用的下拉电阻值太小的缘故，您将上拉电阻换大一些再看波形怎样？