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Current Sweep on k2440 is scaled when Vcompliance is reach

Posted: May 16th, 2011, 9:54 am
by jhowrad
I am doing a linear step current sweep from -130ma to 130ma in 5mA steps using a k2400(LOG sweep does the same),
V comp is set to 8v.
I init the sweep, the k2400 starts @-103mA and ends @130mA as seen on the dsiplay.
I transfer the buffer and plot and it shows the sweep starts and ends at ~ +-60mA keeping the number of steps correct. There are several points at compliance on either end.
Does the K2400 automatically scale the dCi when it hits compliance on a memory sweep? I don't see any reference of this in the tech manual.
I can increase the current range by increasing Vcomp. Of course if I never hit vcompliance the entire current range sepcified is in the buffer.

Re: Current Sweep on k2440 is scaled when Vcompliance is rea

Posted: May 17th, 2011, 5:45 am
by Dale C
When sourcing current and the Model 2400 goes into compliance, the unit is now sourcing voltage at the compliance limit. It is no longer a current source.
This maybe the reason you are seeing the current range shift.
Sometimes it is advantageous to go into compliance, but not in this case.
I would recommend to either increase the compliance level(if your device can take it) or decrease the current level so as not to go into compliance.