Tektronix Keithley SourceMeter 2450 - Page 86

Section
8: Rechargeable battery measurements Model 2450 SourceMeter® Instrument
User's Manual
8-8 2450-900-01 Rev. E / August 2019
SMU
command or
pseudocode
Commands Description
SMU
command
*RST
OUTP:SMOD HIMP
SENS:RES:RSEN ON
SOUR:FUNC VOLT
SOUR:VOLT 1
SOUR:VOLT:READ:BACK ON
SOUR:VOLT:RANG 2
SOUR:VOLT:ILIM 460e-3
SENS:FUNC "CURR"
SENS:CURR:RANG 1
OUTP ON
 Reset the instrument.
 Turn on high-impedance output mode.
 Set to 4-wire sense mode.
 Set to source voltage.
 Set source level to 1 V.
 Turn on source readback.
 Set source range to 2 V.
 Set the source limit to 460 mA.
 Set to measure current.
 Set current range to 1 A.
 Turn the output on.
Pseudocode
iteration = 1
voltLimit = 1.0
current = []
voltage = []
seconds = []
hours = []
while true do:
 Create a variable called iteration
and initialize to 1.
 Create a variable called voltLimit
and initialize to 1.
 Create an empty array for current
measurements.
 Create an empty array for voltage
measurements.
 Create an empty array for the time
values.
 Start a
while
loop.
SMU
command
current[iteration] = READ?
"defbuffer1"
voltage[iteration] = TRAC:DATA?
iteration, iteration,
"defbuffer1", SOUR
seconds[iteration] = TRAC:DATA?
iteration, iteration,
"defbuffer1", REL
 Append the current reading to the
array current.
 Append the voltage reading to the
array voltage.
 Append the time reading to the array
seconds.
Pseudocode
hours[iteration] =
seconds[iteration]/3600
print(voltage[iteration],
current[iteration],
hours[iteration])
if voltage[iteration] <=
voltLimit then:
break
end if
iteration = iteration + 1
delay(10)
end while
 Calculate the hours taken at each
iteration.
 Print the measured values.
 Compare the voltage reading from this
iteration to the voltage limit. If the
measured value is less than or equal
to the limit, break out of the loop.
 End the if statement.
 Increment the iteration count by 1.
 Delay for 10 seconds.
 End the while loop.
SMU
command
OUTP OFF
 Turn the output off.