Section 4: Operation
Series 2600B System SourceMeter® instrument User's Manual
4-26
2600BS-900-01 Rev. A / August 2021
Floating a SMU
Using an external source in the test system may require that a 2600B source-measure unit (SMU)
float off chassis earth ground. An example of such a test system is shown below, which includes an
external voltage source. Notice that output low of the external voltage source is connected to chassis
earth ground.
For the test circuit shown below, the 2600B must float off chassis earth ground. As shown, LO of the
2600B is fl10 V above chassis earth ground. If LO of the 2600B was instead connected to
chassis ground, the external voltage source would be shorted to the chassis ground.
Figure 38: Schematic of floating the Series 2600B
1
2600B LO not connected to chassis ground (floating)
2
Chassis
3
SMU voltage source
4
2600B chassis connected to chassis earth ground through the power cord
5
Chassis earth ground
6
Source chassis connected to chassis earth ground through the power cord
7
Output low connected to chassis
8
External source
9
DUT
The 2600B connections for the floating configuration are shown in the following figure. This figure
shows the 2602B, 2604B, 2612B, or 2614B shown. The 2601B and 2611B are similar.
