An accurate, self-checking digital teraohmmeter

We describe a new digital teraohmmeter achieving state-of-the-art linearity and long-term stability through the application of automatic self-checking circuits and routines. To ensure its voltage-independence up to 1000 V and <100 ppm linearity in measuring 10/sup 5/ to 10/sup 15/ /spl Omega/ (at /spl ges/1 pA), internal scaling and timing circuits have been upgraded for higher speed and better performance.<
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