Digital micro ohm meters for measure low resistance with high accuracy
The most commonly measured electrical parameter is impedance which is measured as a function of frequency. Measuring impedances in the range of ohms with high accuracy is usually easier, however the real challenge comes when the measurement range moves towards micro ohm range. Various factors need to be considered to make high fidelity micro ohm impedance measurements. Ultra-low impedance measurements are commonly performed to assess the quality of high-performance microprocessor power distribution network (PDN) designs. In these applications, the impedance must be measured over a wide range of frequencies starting from DC to hundreds of MHz. Clean power is an important aspect in PDN design. Lower PDN impedance is better for a good microprocessor power supply. Lower impedance filters the power supply noise and provides cleaner power supply to the processor. Conventionally, the PDN is assessed using a benchmark figure called as target impedance which is the ratio of maximum...