PXIe-4145 SMU - Will Switching from Using Local to Remote Sense Affect VOUT Slew Rate?

[aaronb]

While using a PXIe-4145 SMU, will switching from using Local to Remote sense have any significant effect to vout slew/ramp rate? If so, will it theoretically make for faster/slower ramp? I was going to spend some time to wire it up and connect a scope and measure it but I figured I may be able to get a quicker answer here first. My DUT draws ~250uA @ 1.8V VDD.

[SamuRei]

Hi aaronb,

My initial impression of this is: no, using local vs remote sense will not affect the slew rate. This would be a characteristic that is dependent on the PXIe-4145 and the impedance of the DUT. Local and remote sense both take feedback from the voltage output to determine how the power supply needs to behave.

The difference is that local sense measures the voltage at the SMU output terminals whereas remote sense will take the voltage drop in the leads by measuring the voltage at the lead ends; so a voltage is being measured either way and I don't believe the slew rate will be affected between the two cases. I still recommend giving it a shot on your end, but my hunch is that you won't see any differences in slew rate by changing this setting.

Best,

[aaronb · Accepted solution]

So I physically measured slew rates with sense set to local and remote with remote sense lines wired out to DUT and it did have a slight change to slew rate the higher in voltage the SMU was set. At 1.8V I saw no change between local and remote sense but at 3.6V and higher I started to see that the slew rate was slightly (ie. ~100uS) faster using remote sense vs. local sense but only at the "slow" SMU transient response setting. At 3.6V local sense with "slow" transient response setting I saw 1.06mS while for remote sense I measured 954.8uS; 105.2uS faster.