SP1018G - Switching to 5V pull-ups doesn't work

Logic Analyzers ScanaStudio
1

My circuit has a signal where a chip is sending LOW (0V) or HIGH (5V) to a CPU GPIO pin which is configured to be a high impedance input. Attached is a 10k pull-up resistor against 5V. When I connect the analyzer with activated 10k pull-up at 5V logic the signal voltage changes to be only 4V. This is the influence of the analyzer input.

Check:
When I select in ScanaStudio to have input pull-ups with 5V logic level I expect to see the 5V when I’m connecting a meter to the naked anayzer input. What I see is always 3.2V, no matter how the logic selection has been done. (snapshot).

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This means the logic level selection only has an effect on the logic threshold but not on the physical voltage the internal pull-up is connected to. This results in the effect described above.

2

Hello @Olaf

Sorry for the late reply. Indeed, the new revision (actually in production) enhances this part. in addition to being able to select between pull UP/DOWN 10K Ohm resistor and 1M Ohm resistance, you’ll also be able to select the pull voltage.

3

Hi. What’s the status regarding this topic?
Without this feature the area of use is really limited.