Agilent/Keysight Power Supplies, Sense circuitry

[R. Johnson]

Hey all,

I'm working on an industrial project that requires a super low noise voltage source that is GPIB controlled, 0-100V. The existing equipment utilizes 6634B power supplies, but requirements have gotten more intense and they're too noisy. We've been playing with a B2901 SMU, and it isn't much better. A capacitive multiplier solves the issue, and the test works beautifully.

Only issue now is the voltage drop. I tried using the sense+ wired to the output of the active filter but that just sends the 6634B into protection mode. I thought the B2901 was going to work because the output corrects measured with a basic DMM to the right voltage, but looking at it on a scope it is oscillating at some low distorted freq. I could characterize the voltage drop and adjust the GPIB software to compensate for it, but it seems there should be a more elegant solution for correction that I'm not seeing.