Original Thaler Corp VRE305 Voltage reference. I bought it from a seller in Israel for $35 shipping included. This is opposed to $75 for the new APEX VRE305 from Digikey.
My APEX chip is drifting well out of specification...about +100uV since Jan 2nd of this year. Previously the IC had been in an aging fixture for 5 months. During that 5 months it also drifted up...roughly +300uV. The specification is 6ppm per 1000 hours...it's pretty close to 1000hrs from Jan2 to now and 6ppm is 30uV. A factor of 3 high. 5 months would be 3600 hours or 22ppm or 110uV...again about a factor of three high. This is actually my 2nd APEX VRE305. The first one was replaced by APEX because its output voltage was a factor of 2 out of specification from the get-go. APEX was responsive to my complaint and sent the replacement FedEx to my home in Philippines. They only required that I mail them the old chip for testing.
I have heard that the original Thalar chips met their specifications, so I will test this one for a few months and we shall see what happens.