Keithley 2635 Reference Manual

8-18 Return to Section Topics 2600S-901-01 Rev. C / January 2008
Section 8: Source-Measure Concepts Series 2600 System SourceMeter® Instruments Reference Manual
CAUTION V-Compliance must be set to a level that is higher than the measured
voltage. Otherwise, excessive current will flow into the SourceMeter. This
current could damage the SourceMeter. Also, when connecting an external
voltage to the I-Source, set the output off state to the high-impedance
mode. See “"Compliance limit"” earlier in this section for details.
In Figure 8-13B, the SourceMeter is configured to measure current-only by setting it to source 0V
and measure current. Note that in order to obtain positive (+) readings, conventional current must
flow from IN/OUT HI to LO.
Figure 8-13
Measure only configuration
V-Meter
I-Source
(0.00000mA)
A. Measure Voltage Only
IN/OUT HI
IN/OUT
LO
±
DUT (V-Source)
I-Meter
V-Source
(000.000mV)
B. Measure Current Only
IN/OUT HI
IN/OUT
LO
DUT (I-Source)
Positive
Current
Note: Positive current flowing out of
IN/OUT HI results in positive (+)
measurements.
Note: Use 2-wire local sensing.
s
Contact check
When a contact check measurement is being performed, two small current sources are switched
in between the HI and SENSE HI terminals and the LO and SENSE LO terminals. By controlling
the switches illustrated in
Figure 8-14, the current from these sources flows through the test leads
and through the contact resistance as shown. To accurately measure the resulting contact
resistance, the differential amplifier outputs are measured once with the current sources
connected, and again with the current sources disconnected. This allows for compensation of
various offset voltages that can occur.

Keithley 2635 Specifications

General

Brand	Keithley
Model	2635
Category	Measuring Instruments
Language	English