Re: Mitigating Signal Reflection

On Mon, 18 Mar 2024 00:12:14 GMT, Dan <dan@nospam.invalid> wrote:

I'm new to electronics and I'm hitting an issue beyond my skill set. I
should start by saying I'm not 100% sure signal reflection is the issue,
but it's my best guess.
>
I have a 3.3V clock signal that I'm trying to convert to 5V. The clock
speeds are sub 100 kHz. I'm using a TI level shifter, TXS0108E. Looking
at the signal on a scope, it's a clean signal on the input and output
side when I don't have anything connected on the output side.
>
When I hook up the clock signal on the output side, over an
approximately 1 meter wire the signal on the scope is full of noise. The
scope also says the frequency is much higher than one the input signal
should generate. I see the noise push through to the input side. I'm
assuming this is because the level-shifter is bi-directional.
>
I've tried a few failed solutions, like using a diode to try and block
out the reflections, but so far no luck.
>
Any advice on how to deal with this?

There's a possibility the fault could arise through improper use of
the level shifter, making it tip into self-oscillation when a load is
connected. This is not uncommon with voltage regulators as well. I
would suggest you strictly follow the recommendations on the data
sheet in regards to any ancillary components this device may require.