Section 2: General operation
2606B System SourceMeter® Instrument Reference Manual
2-50
2606B-901-01 Rev. B / May 2018
-- Restore 2606B defaults.
smua.reset()
-- Select voltage source function.
smua.source.func = smua.OUTPUT_DCVOLTS
-- Enable source autoranging.
smua.source.autorangev = smua.AUTORANGE_ON
-- Set voltage source to 5 V.
smua.source.levelv = 5
-- Set current limit to 50 mA.
smua.source.limiti = 50e-3
-- Set current range to auto.
smua.measure.autorangei = smua.AUTORANGE_ON
-- Turn on output.
smua.source.output = smua.OUTPUT_ON
-- Get power reading.
print(smua.measure.p())
-- Turn off output.
smua.source.output = smua.OUTPUT_OFF
Contact check measurements
The contact check function prevents measurements that may be in error due to excessive resistance
in the force or sense leads when making remotely sensed (Kelvin) measurements. Potential sources
for this resistance include poor contact at the device under test (DUT), failing relay contacts on a
switching card, and wires that are too long or thin. To use contact check, the current limit must be at
least 1 mA (this allows enough current to flow when performing the test), and the source-measure
unit (SMU) must not be in High-Z output-off mode.
The contact check function will also detect an open circuit that may occur when a four-point probe is
misplaced or misaligned. This relationship is shown schematically in the figure titled "Contact check
measurements," where R
C
is the resistance of the mechanical contact at the DUT, and R
S
is the
series resistance of relays and cables.
Figure 26: Contact check measurements
