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| 50G ohm Retirement Fund |
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| nitro2k01:
If you have nothing better to do, hook up say 100 of them in parallel and see if it checks out to about 500M, which would be a more easily measurable value. Or hook up a few of them in parallel and see if they measure as a capacitors I guess. I have a hard time seeing where something like a 50G ohm resistor in such a small package would be useful. Maybe in something that is potted, but then again just the resin would probably contribute a not insignificant stray resistance. So hmm... Would love to see a "teardown" of it though. Maybe polishing one layer at a time off of it to reveal its internal structure. Maybe send the whole bag, or a carefully selected sample, to mikeselectricstuff? |
| AndyC_772:
Factory rejects. They were supposed to be 10k, but someone forgot to apply the metal film and just left the ceramic substrate. :-DD |
| Alex Nikitin:
--- Quote from: Bryan on March 15, 2017, 05:34:09 am ---For what application what would a 50Gohm resistor be used for? --- End quote --- Electrometers. At work I routinely use 20G and 100G resistors and plan to use SMD parts of these values in a near future. The application in my case is Quadrupole Mass Spectrometry. Similar electrometers are used in many other applications where very small charges/currents have to be measured or sensed. The current noise level is reduced with the increase in the resistor value, so larger the value, lower the noise (but slower the response due to a parasitic capacitance). 20G resistor has about 1fA RMS self-noise in 1Hz BW. 50G resistor - about 0.6fA. I can also add that it is perfectly possible to use SMD parts with these values. If somebody would like to know the details, than the ADA4530-1 datasheet, evaluation board description and AN-1373 application note can provide a good starting point. Cheers Alex |
| tszaboo:
--- Quote from: boffin on March 15, 2017, 06:26:33 am ---You sure they're not caps? I say that due to the colour, sort of a yellowish which is pretty common with ceramic caps. --- End quote --- Preatty much, what I would have said. 50Gohm on a pcb in a 0805 package is a part not soldered in... |
| alm:
Well, 50 GOhm resistors do exist in 0805 (up to 100 GOhm in that series). Make sure you do not exceed that 1/8 W power rating ;). |
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