AM450e User Manual
AEMULUS
16
3.2 SMU Connection
There are 5 leads per channel:
1.
Guard
2.
Force-High
3.
Force-Low
4.
Sense-High
5.
Sense-Low
Force-High and Force-Low outputs are where voltage and current are generated during source
or sink operation.
Sense-High and Sense-Low outputs are high impedance paths. Connect these lines as close to
the DUT terminal as possible for more accurate voltage source or measure operations.
Presence of Sense lines at the DUT terminals is known as 4-wire, remote-sense, or Kelvin
operation.
For high power device testing, there can be significant voltage drops in test leads due to the
high current flow. Using remote sense becomes very critical to ensure accurate source and
measure operation. Advantages of using 4-wires measurement:
1.
It eliminates the resistance of your interface cabling
2.
Lengthy wires would not be an issue anymore
3.
It allows measurements on lower resistance values than 2-wire testing
Guard terminal is a low impedance output that is very close to the signal voltage on the Force-
High output. Typically, the Guard output is kept within 2mV on the Force-High output.
