Andreas_-_Jahn at t-online.de
Mon Sep 13 22:03:33 UTC 2010
I want to build my first home made LTZ1000A-Reference the next days and
found an elder post:
> As volt standards, I own a Fluke 5442A, and a home made double LTZ1000
> standard, which has still to be improved.
> Currently, I search for the root cause of voltage spikes in the output
> of the LTZ1000 references (suppose shielding/grounding issues).
Did you find the root cause of the spikes? Eventually your experiences
would help me to avoid some errors.
My planned cirquit uses the datasheet cirquit as a base with
for the zener voltage to avoid starting issues. Further to reduce the
of the LT1013 I have an (optional) BF245C J-FET as power-stage
for the zener current.
The power-supply is based on 12 NiMh-Cells which are regulated
by a LTC1763 down to 14.0 V. The whole is packaged in a EURO-sized
aluminium metal case together with a L200-based simple charger
and a undervoltage detection cirquit which switches off in case of
The area around the LTZ1000A can be shielded with a tin can
For the first step I did no mechanical stress relief like in the
datron reference. With my UPW50-resistors (3ppm) there
is not enough place within the inner shield to do this.
More information about the volt-nuts