correct triggering of keithley 236 SMU using labview

[vaio2011]

Hello All,

I am new to both labview and also using an SMU. My aim is to attain voltage current curves of solar cell devices by  sweeping voltages and measuring current. I am having difficulty in triggering correctly. I am using an example sweep I obtained from the kiethley website (attached). I think  the triggering is currently on continous (H0X)  and I am not sure if this is what I need. The graphs I am getting are definately not what I expected. I am using a linear stair sweep; and I wish to sweep voltages from -1 to 1V and meassure current. What kind of triggering should I have for this? and Is it simply a matter of replacing the H0X with the relevant T*,*,*,*X code. Although this may not be relevant for this forum, the only connection I have to my DUT are the output Hi and Output low. I just wanted to clarify if i needed any more connections.

many thanks 

[nitad54448]

hi

i think that 236 is an old version,.. I was doing what you are asking for with a Keithley 2400.

so, you need to look in the instruction manual of 236 for :

apply voltage, read current

then in a while loop, use a shift register, add the step value and : apply voltage, read current, add step, ect, until the upper limit is reached.

N

[S.Limb]

Hi

I have been looking into your query and also at your code, I have a few suggestions for you to look into and then you can ask further questions if needed.

From the information you have given, I think your main task is to find out from Keithley what the access commands are for the trigger and then you will be able to understand how to get the trigger working.

I have made a few changes to your code, the changes made do not have any effect on the execution order and the functionality, but the execution time will decrease and will also stay low if you follow the same practices. I have taken the structure out of the subvi and documented this for you, I have also made a change to the first part of your main code which allows the error cluster to pass through the functions before the loop. As the code you have is an example I recommend stepping through it and documenting what id=s happening at each step of the code, this will help you understand what you will need to change or remove for this project and future projects.

You mention that you are new to LabVIEW, National Instruments has a great community page and some very helpful tutorials available, I recommend looking at the examples as well, for Keithley products and general LabVIEW practices.

If you have any further questions please reply to this post

Thank you