Today I found at work a printed circuit board with eight LT1013 op-amps all dated 1989. It is an unused spare part board for something trashed a long time ago. As a bonus the single sided copper makes it easy to unsolder the components with minimal heating. According to the LT1013 datasheet the offset long term stability is pretty good: 0.5 uV per month typically for a new device. But even that (if cumulative) can be a problem in the most demanding applications. Is it realistic to expect that those 20+ years old op-amps are much more stable than same type manufactured this year? Will

Hello Will, If they are in a hermetically (metal or ceramic) housing I would expect that they have well stabilized. >From my experiences with my voltage references I can derrive that with a plastic case most of the non cummulative ageing depends on mechanical stress due to relative humidity. After some pre-ageing the output change of the references due to humidity is much larger (about 0.5ppm/% rH giving up to 10 ppm over a 20% rH change) than the drift over time. (which is between 0 .. 3 ppm/year for 2 LT1027CCN8-5 relative to a well pre-aged and hermetically sealed LM399H reference). So if the root cause is similar I would expect similar behaviour from a op-amp. But each treatment of the op-amp like soldering will issue mechanical stress and I would expect that it will at least need some weeks until the device will stabilize again. With best regards Andreas ----- Original Message ----- From: "Will" <willvolts@gmail.com> To: "Discussion of precise voltage measurement" <volt-nuts@febo.com> Sent: Monday, October 17, 2011 2:59 PM Subject: [volt-nuts] LT1013 aging > Today I found at work a printed circuit board with eight LT1013 > op-amps all dated 1989. It is an unused spare part board for something > trashed a long time ago. As a bonus the single sided copper makes it > easy to unsolder the components with minimal heating. > > According to the LT1013 datasheet the offset long term stability is > pretty good: 0.5 uV per month typically for a new device. But even > that (if cumulative) can be a problem in the most demanding > applications. > > Is it realistic to expect that those 20+ years old op-amps are much > more stable than same type manufactured this year? > > Will > > _______________________________________________ > volt-nuts mailing list -- volt-nuts@febo.com > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts > and follow the instructions there.