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2600AS-901-01 Rev. B / September 2008
Return to
2-21
Series 2600A System SourceMeter® Instruments Reference Manual
Section 2: DUT Test Connections
external voltage source. Notice that output low of the voltage source is connected to chassis earth
ground.
For the test circuit shown in
, the Series 2600A must float off chassis earth ground. As
shown, SMU LO of the Series 2600A is fl10V above chassis earth ground. If SMU LO of
the Series 2600A was instead connected to chassis ground, the external voltage source would be
shorted through chassis ground.
The Series 2600A connections for the floating configuration (
) are shown in
. In order to float the SMU, input/output LO must be isolated from chassis ground. This is
accomplished by NOT connecting input/output LO to chassis ground.
The external voltage source in
can instead be a SMU of a second
Series 2600A instrument. Keep in mind that if the combined outputs of the sources exceeds 42V,
then a safety shield will be required for the DUT (see the following WARNINGS).
WARNING
The maximum floating (common mode) voltage for a SMU is ±250V.
Exceeding this level may cause damage to the instrument and
create a shock hazard.
Using an external source to float a SMU could create a shock
hazard in the test circuit. A shock hazard exists whenever >42V
peak is present in the test circuit. Appropriately rated cables or
insulators must be provided for all connections to prevent access
to live parts
When >42V is present, the test circuit must be insulated for the
voltage used or surrounded by a metal safety shield that is
connected to a known safety earth ground and chassis ground (see
Figure 2-31
Floating the Series 2600A
V-source
HI
LO
Series
2600A
SMU
10V
+10V
Chassis Earth Ground
Low
Output low connected
to chassis
Series 2600A LO
NOT connected
to chassis ground
(floating)
High
+
Chassis
Chassis
Source chassis connected to chassis
earth ground through the power cord
External Source
Series 2600A chassis
connected to chassis earth
ground through the power cord
+