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I want to know if the four-terminal resistor and the shunt resistor are the same.

Is there another use for the four-terminal resistor except measuring current?

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1 Answer 1

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This is what I believe you mean: -

enter image description here

It's still a shunt resistor except there are bespoke pads for the measurement circuit. On very low ohmic value shunts this is usually compulsary for the better ones.

A 4 terminal resistor is usually a shunt resistor. But not all shunts have 4 terminals. This picture should explain why the errors are smaller when using bespoke terminals for voltage measurement to infer current: -

enter image description here

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  • \$\begingroup\$ "A 4 terminal resistor is usually a shunt resistor. But not all shunts have 4 terminals." A 4 terminal resistor has a 4-pad for me a shunt resistor has 2-pad layout which is important for the measurement accuracy. \$\endgroup\$
    – R Djorane
    Commented Sep 25, 2015 at 12:51
  • \$\begingroup\$ @codo Then we disagree if I understand you correctly! \$\endgroup\$
    – Andy aka
    Commented Sep 25, 2015 at 12:52
  • \$\begingroup\$ how do you solder a 2 terminal resistor to be 4 terminal, you need 4-pad layout resistor for better measurement accuracy \$\endgroup\$
    – R Djorane
    Commented Sep 25, 2015 at 12:56
  • \$\begingroup\$ You can't - if it has 2 terminals then any attempt to increase the number of terminals is pointless. \$\endgroup\$
    – Andy aka
    Commented Sep 25, 2015 at 13:19
  • \$\begingroup\$ @Andy: Why wouldn't two pads work, as long as you have extra traces running to them for the sense circuit? The "four pad" footprint helps PCB layout software, because it keeps the sense signals on a different logical net and avoids moving the branch point away from the sense resistor... but does it provide any real benefit? \$\endgroup\$
    – Ben Voigt
    Commented Sep 25, 2015 at 16:45

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