Can't set up Keysight B2912B SMU to output Current List (outputting Voltage list works fine)

[Tabahof]

Hello, World!

Can't figure out what's wrong with my Labview 2020 programm I'm trying to use to control B2912B SMU. I've downloaded LW driver pack from ni.com (pack for LW 2015). Loaded "Agilent B2900 Series Output List Sweep Volts.VI" from examples folder. If I'm using this .VI as it is, sourcing Voltage and measuring Current - it works (pic 1,2). Then If I modify it to souce Current and measure Voltage (changing "List Sweep Setting Mode" to current and "Meas" option to Voltage) it outputs result I can't explain (all current points are 0.00033A instead of 0-1-2-1-0 uA ladder) and unexpected Voltage measurements (pic 3,4). What am I doing wrong?
SMU Force and Sense terminals are connected to 20kOhm resistor (4-Wire connection).

Please help.

[AnalogKid2DigitalMan]

Is there a setting for compliance voltage when in current sourcing mode? Perhaps you are exceeding that voltage setting ~6.6V (.00033A x 20kohms)?

-AK2DM

[Tabahof]

Compliance input is not connected and defaulted to 2V.

And if I wait long enough (with PLC=100) I reach it (all Voltage measurements are around "-2V"); current reading where something 0.0001A. 100 times higher of programmed Current 😞

[cstorey]

i see you have change these but have you used the highlight execution to see what the actual commands sent to the SMU are?  Express current in Scientific notation, rather than decimal or engineering.

Hope that helps.

Craig

[Tabahof]

So I've probed VISA Write in first 4 .subVI after Initiate.VI with default settings (Voltage set in Configure Source.VI and Current set in Configure Measurement.VI) which is working fine; and Source Current, measure Voltage setting - which is not (see pic. 5).

In that picture first string is probed in Sce Volt, Meas Curr and second string is Sce Curr, Meas Volt.

Didn't notice anything odd there.

I've also tried to change numbers to scientiic notation - din't help.

[Tabahof · Accepted solution]

I've solved this problem after connecting something meanigfull to "Source range" Input of Configure Source.vi.
I was relying on "Source - Auto range" input On by default and that's why I don't have to connect "Source range" input by myself. But Source - Auto range input of Configure Source.vi don't work (whatever you input there Source Auto range will be Off).

And if you want Source Auto range On you need to VISA Write ":SOUR1:VOLT:RANG:AUTO ON;" after "Configure Source.vi".

Also found a bug in this driver pack - I couldn't control second channel of SMU and the reason was the absence of :SOUR2 before ":FUNC: MODE VOLT;" and ":FUNC:TRIG:CONT ON;" strings in Configure Source.vi