Keithley 1132 Low Voltage AN free download

File name 1132_Low_Voltage_AN.pdf

Number 200 Application Note Understanding Low Voltage Series Measurements Introduction Reducing circuit resistance can reduce noise in some instances. However, it does not diminish problems when sensing Techniques for making precision, accurate voltage measurements current since it reduces the signal more than the thermal noise. are fairly well known. But a lot of these methods fall short when For example, reducing the resistance of a current-measuring resolution must be extended below one microvolt, which is often shunt by a factor of 100 cuts noise by a factor of 10. But from the case when measuring physical parameters in industry such as Ohm's law, reducing resistance by 100 also cuts the voltage to be temperature, pressure, force, etc. measured by 100, thus making the noise voltage proportionally For example, industrial temperature measurements often larger. require resolution of 0.1