XTR111: Self generation current meander on output

Hi Ruslan,

I'm not sure I understand the question, could you please elaborate? If you mean will the XTR generate a signal without an applied input then no, this should not be the case. If you are powering your input circuitry from the XTR then at zero input the output will correspond to the current drawn by your input circuitry. If you are seeing something else than there may be something wrong with your configuration. If you can share a schematic I would be happy to take a look at it for you.

Hi, Zak,

Sorry for my English.

I mean if XTR111 have any internal failure (any kind of) is it possible theoretically self generation current on output?

Thank you.

Hi Ruslan,

No problem at all, I understand now. I have to preface this by saying the XTR111 was not explicitly designed for safety critical applications and we do not do extensive analysis on all of the different ways the device could potentially fail as this largely depends on the application.

That being said, in looking over the topology of the device I do not see a way in which the device itself would fail to produce an output current with a 0V input. There will be a slight amount of leakage current from the output transistor, but this will be negligibly small.

A couple things that could potentially result in an output current when you are not expecting it:

1) If the output transistor is damaged, possibly from a large power supply transient, then you may see the leakage current increase dramatically.
2) I have seen multiple cases where residual flux contamination on the board from improper cleaning can produce parasitic paths to the input. In the case of the XTR111, the most likely culprit would be the output of the onboard regulator coupling to the input pin and pulling it up to some non-zero voltage, which will raise your output level. This can be easily mitigated by following proper board cleaning practices or guarding the pins in layout.

Thank you for your answer.
For our application static signal is not important and safety. Because we generate current signal with frequency 10Hz with different level. This way protects us from leakage current. However, XTR111 have feedback inside IC so we worried about possibility to self generation frequency 10Hz when on input pin is static signal.

Hello.

Could somebody answer me on my question? It is very important for one International project.

Maybe somebody know where can I find this information?