Yes, LM399 good good! Me like! The dozen LM399 have now spent a day at an average 0.0uV deviation, +/-0.2u peak to peak probably below 0.1ppm rms (10s averaged), despite the room temperature changing by something like 5 degrees (C). Condition; Bench supply 12V, 12 IC paralleled, current limited by 2K7 to each IC, output via 2K7 from each. I got my LM399 from ebay at $4.99 each. Seller polida2008. (I'm in no way associated with the seller). Buying ICs on Ebay is risky but these where good.

Hello, I do not know how you measure the "noise". If its 0.1-10Hz peak-peak noise a value of 10uVpp is rather high. Typical noise should be around 4.2uVpp (0.6ppm peak peak) for a zener with around 1mA current. The LM399 that I have measured range from below 3uVpp to around 7uVpp. Perhaps you should do some thermal isolation around the LM399. Additional use a 100nF decoupling capacitor at Input (heater) and output (zener). By the way: there are 2 threads on the eevblog regarding LM399 + LTZ1000 http://www.eevblog.com/forum/projects/lm399-based-10-v-reference/ http://www.eevblog.com/forum/projects/ultra-precision-reference-ltz1000/ With best regards Andreas Am 29.03.2014 15:57, schrieb Jan Fredriksson: > Yes, LM399 good good! Me like! > > The dozen LM399 have now spent a day at an average 0.0uV deviation, +/-0.2u > peak to peak probably below 0.1ppm rms (10s averaged), despite the room > temperature changing by something like 5 degrees (C). Condition; Bench > supply 12V, 12 IC paralleled, current limited by 2K7 to each IC, output via > 2K7 from each. > > I got my LM399 from ebay at $4.99 each. Seller polida2008. (I'm in no way > associated with the seller). Buying ICs on Ebay is risky but these where > good. > _______________________________________________ > 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.