TIFU (well yesterday but it's the same) shorting VCC to gnd through my uCurrent Gold albeit for a couple of seconds.
Although I set a limit of 20mA on the psu, it seems that I have damaged the thing.
Since I have no skill in diagnosing and repairing such things (and have a limited supply of tools), I thought this could be a good "project" but I need your guidance.
Here's a recap:
SymptomsAfter doing the wrong thing, the microcurrent (it was in the milliamp range) ALWAYS shows up negative values upon powerup with the PSU disconnected.
Nothing appears blown or damaged upon visual inspection. The LED still turns on when switching on.
I tried a couple of measurements and they seem kinda off, but I don't know how to determine whether the microcurrent is really cooked or if it's fine.
First of all it gives very low readings without taking the delta for the negative starting offset. Even after doing the delta It is off wrt my EEVBlog BM235 and Keithley DM6500 of 2-3mA over a range from 5 to 20mA. Both the other meters show the same value more or less.
The same applies for the microcurrent range where the uCurrent shows values of ~100uA less than the other multimeters (around 350 uA vs 470uA). The measurements have been done using a npn current sink roughly programmed.
Anyhow the microcurrent values are always wobbly and never stable.
They were not this way before.
QuestionsCan this be my paranoia and the discrepancies justified by burden voltage of the meters? I probed with either meter and the micro current separately.
What can I do to see whether there's something wrong?
Can you help/guide me step by step plz?
Tools I have- DM6500
- BM235
- Scope->SDS1104X-e (iirc, it's the 100MHz 4 Channel Siglent)
- Linear siglent PSU (I don't recall the model unfortunately)
- DER EE LCR meter
- Hakko FX888D soldering iron with some tips
I think other stuff don't matter, but notably i do not have a hot air gun/station.
Cheers