INSTRUMENTATION CIRCUIT FOR SHUNT-BASED METROLOGY MEASUREMENT

摘要

The present subject matter is directed to methods and apparatus for measuring current flow from a source at a first frequency using matched voltage drops in paired voltage drop circuits. The paired voltage drop circuits each comprise a fixed value component, such as a resistor, and an adjustable value component, such as an adjustable current source, coupled in series. The adjustable valued components are controlled based on differences in voltage drops produced by the voltage drop circuits based on a high-frequency signal, higher in frequency than the first frequency, applied to a control input for the adjustable value components.