Andrea C

You should probably talk this over with your local applications engineer.

What is the maximum short circuit current from your device?

I am guessing the SMU is used in force voltage and limit current mode with your solar PN junction.
You might be encountering current compliance or range compliance.  Anything on the front panel of 2400 go to flashing on/off when you open the shutter?

Can you explain the 3-sigma value?  How compute it?

In your config, what sort of speed settings?  Use Quiet if looking for small standard deviations.

It looks like your DUT value is a few single digit pF.
At 1KHz, it will be very big Z and very small current relative to using higher test freq.
In our datasheet for CVU, we do not publish value for pF at 1KHz.

 

Sure, it is possible.

For older 4200, they can connect to external instruments on gpib or LAN (raw socket).
The newer 4200A-SCS adds usb and VISA for connection to external instruments.

The scope you mention has both LAN and USB.

For the software environment to send commands to scope and read data back, a library would be written using KULT tool.  Depending on your overall objectives, the code you write with KULT can also interact with the SMU, CVU or PMU hardware in your 4200/4200A.  The compiled library is run from KITE or Clarius UTM (user test module).  KXCI can also call user libraries.

Take a look at example KULT libraries on your system.  Ones for temperature control or for external LCR meter can give you an idea of interaction with external instruments.
 

Yes, that can be done.

In general, follow the Guidelines for combining SMU outputs in the Reference manual (section 2).

For two current sources in particular, make sure to have the voltage compliance limits a little bit different from each other.

To have same timing behavior from each SMU, use same ranges and other settings on each.

Also, sometimes the order of starting their trigger models matters.  For example, if SMUB is consuming an output event from SMUA to get things started, make sure to call the trigger initiate for SMUB first so that it can be fully armed and awaiting the events.

Are you using a fixed source range?  If the source range is also using auto, then the discontinuity could be for the hand-off of 200mV to 2V range as you sweep to 250mV.  A source range can go to 101% of its full-scale value.

For the data in the buffer, look at the measurerange and sourcerange attributes.  And perhaps post a CSV with your I, V, timestamp and the range information.
Try setting the smu sourcerange to a fixed value that can handle all the desired source levels (2V in your case).

When was last time your instrument was calibrated?
 

The CVU can source the DC bias at both CVUHI and CVULO.
To put the bias tees into CV mode, source -10 at each terminal from CVU.
The blocking cap of the bias tee will prevent this -10V from reaching DUT;  instead the bias from the SMU passes thru.

You are writing custom code to control it all?
Our ACS or ACS-Basic software has HVCV libraries for this configuration.

Depending on the connection rule in use, when moving to next channel in a scan, the opening of prior channel and closing of next can occur simultaneously or can be configured for break before make, etc.

In general the scan is just closing, measure, open/close next channel, measure, etc.

Since a measure function is associated with the scan, the instrument will also manage the backplane relays to connect the switch to the internal DMM.

Measure count of 10 would give 10 individual readings in the buffer.
To obtain an average, you could use a digital filter.  The instrument has both moving and repeating average filter.
Or there are buffer statistics that you can query to obtain mean, std dev, etc.

Yes.
Next to last page of data sheet lists the PC recommendations/requirements.
Windows 11 is supported.
Datasheet

In event log on the instrument, try turning on command logging.
Sounds like a syntax error.
Video on command logging:  https://www.youtube.com/watch?v=cVU_C308EUc

Or try NI IO Trace to see what is happening on the bus.