Core power rails are now routinely in the 1 kAmp to 2 kAmp range, requiring a power distribution network (PDN) impedance in the range of 20 µΩ to 30 µΩ.
I am known for saying “Measure something you know before measuring something you do not; and of the same order of magnitude.”
This makes sense. It provides a validation of your measurement setup, and it assures that the measurements you are going to make are within the dynamic range of the setup. If you wanted to measure 100 µΩ, proving that you get the correct answer when measuring 1 Ω would be less than adequate. It does not prove that 100 µΩ is within the dynamic range of your setup.
This results in a new challenge. Where do we find a 20 µΩ known measurement standard? Resistors are available off-the-shelf at 250 µΩ, but I have not seen any usable test standards in the 20 µΩ range. With a significant number of customers now looking for these standards, and Picotest’s goal of helping our customers with their power integrity measurement challenges, we have created resistor standards.
