Section 3: Operation
Model 2000-SCAN Scanner Card User's Manual
3-10
2000-SCAN-900-01 Rev. A / April 2018
Four-wire resistance tests
Precise measurements over a range of system and DUT conditions can be obtained by using the
4-wire measurement scheme shown below. Separate sense leads from the DMM6500 are routed
through the scanner card to the DUT. The extra set of sense leads minimizes the effects of voltage
drops across the test leads, reducing measurement errors with lower DUT resistances. Note that an
extra two poles of switching are required for each resistor tested. Only five resistors can be tested
using this configuration. The second figure shows an equivalent circuit for the 4-wire resistance test.
