[volt-nuts] LM399 Long term drift specification

[M K]

On 15/09/2014 17:57, Tony wrote:
> On 14/09/2014 18:29, Andreas Jahn wrote:
>> By the way:
>>
>> By accident I have found some ageing drift data of REF5050 on 
>> Malone's homepage:
>> http://www.voltagestandard.com/Tech_Data.html
>> For me it looks around 120 ppm drift within the first year.
>> Unfortunately there is no humidity data with the plot.
>>
>> With best regards
>>
>> Andreas
> That's a very interesting find Andreas, thanks. After approx 500 
> hours, maximum drift is approx 80ppm, but its impossible to deduce how 
> much of that is due to long term drift, temperature and humidity changes.
>
> The long term drift specification for the REF5050A tested is 125ppm 
> (0-1000 hours), 45ppm (1000 to 2000 hours). Those for the automotive 
> qualified REF5050-Q1 part are 100ppm and 10ppm respectively - way 
> better after the initial 1k hours.
>
> Regards,
>
>  Tony H
One thing that concerns me is that all 5 units seem to drift in sync, so 
how much of that is the DVM doing the measuring? or is it just a single 
batch with the same date code?