Keithley 2635 Reference Manual

4-14 Return to Section Topics 2600S-901-01 Rev. C / January 2008
Section 4: Basic Operation Series 2600 System SourceMeter® Instruments Reference Manual
Figure 4-2
2-wire resistance sensing
SourceMeter
HI
LO
I
V
M
Input, Output
V
M
V
R
Test Current (I)
Resistance
Under Test
Lead
Resistances
R
S
R
LEAD
R
LEAD
= Current sourced by SourceMeter
= Voltage measured by SourceMeter
= Voltage across resistor
I
V
M
V
R
Measured resistance = = + (2 X )
Actual resistance = =
V
M
I
R
S
R
LEAD
I
V
R
R
S
Figure 4-3
4-wire resistance sensing
SourceMeter
4-wire Sense HI
4-wire Sense LO
I
Input/Output HI
V
M
V
R
Test Current (I)
Resistance
Under Test
Lead
Resistances
R
S
R
LEAD
R
LEAD
= Current sourced by SourceMeter
= Voltage measured by SourceMeter
= Voltage across resistor
I
V
M
V
R
and measured resistance = =
V
M
I
V
M
Sense Current (pA)
Input/Output LO
R
LEAD
R
LEAD
Because sense current is negligible, =
V
M
V
R
I
V
R
=
R
S
Sense selection
Front panel sense selection
To select sensing mode:
1. Press the CONFIG key then press MEAS. Choose V-MEAS, and then press ENTER or the
Rotary Knob.

Keithley 2635 Specifications

General

Brand	Keithley
Model	2635
Category	Measuring Instruments
Language	English