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Digital micro ohm meters for measure low resistance with high accuracy

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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...
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Fundamentals and Measurement Guide For Vector Network Analyzer

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Vector network analyzer (VNA) is a measuring instrument which is primarily used to measure S parameters which determines RF (radio frequency) performance microwave devices. VNA is also called as a gain phase meter due to the fact that they are able to measure both the gain and phase of the device under test. They were also called Automatic Network Analyzer in the 1970s, even though the most popular term is VNA. Some vendors like Keysight prefer the term PNA, which can refer to Performance Network Analyzers.  Nowadays, it is getting popular among power electronic engineers too due to the high accuracy measurements required for control loop stability and impedance measurements. They can be used to characterize active and passive devices. Active devices include amplifiers, opamps, mixers, and tuners. Passive devices includes capacitors, inductors, ferrites and resistors. In general, they can be used to characterize a device with excellent accuracy since the measurements are ba...
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Vector Network Analyzer Measurement - Tools For Power Integrity Measurements

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(VNA) is a measuring instrument which is primarily used for S parameters measurements. They can be used to characterize active and passive devices. Active devices include amplifiers, opamps, mixers, and tuners. Passive devices includes capacitors, inductors, ferrites and resistors. In general, they can be used to characterize a device with excellent accuracy since the measurements are band limited and the fixtures can be de-embedded. Generally, they are costly equipment even though cheaper versions like Omicron Bode 100 are available. Most common VNAs are two port devices, even though higher number of ports are available too. They are commonly used in signal integrity and power integrity measurements. Signal integrity measurements are required to characterize transmission lines accurately which in the end affect the signal quality. Even though the final quality of signal is measured in time domain using time domain reflectometer (TDR), the channel characterizations are performed or a...
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