Evaluation of an alternative null detector for adapted Wheatstone bridge

The adapted Wheatstone bridge technique has been utilized at the National Institute of Standards and Technology (NIST) and other National Metrology Institutes (NMIs) for high resistance measurements. In this work, we evaluate the suitability of a transimpedance amplifier (TIA) as a null detector for the adapted Wheatstone bridge to improve high resistance measurements. Initial resistance measurements using the TIA based null detector showed an order of magnitude improvement in the Type A uncertainty.