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So I'm studying Kilovoltmeters and subsequently using ADC's with resistor arrays and dividers from high voltage power supplies of all varieties.

I've got a good idea as to what they are and how they work, especially in use for SMPSs. However, in my researching I found this weird texas instruments dual-jfet-amp TL062 configuration with amp A being a buffer followed by the other, weirder amp, amp B; this is the main issue here as is described in the title. The power supply is an SMPS with a long chain of Cockcroft-Walton multipliers. The link to the pdf is under the image provided.

The inverting input of B is a 1/2 voltage divider with 100k resistors, and the non inverting input is connected via R2 of the divider and also trails off to an Arduino ADC pin.

I know Op-Amp inputs always want to stay the same if the output is used in a negative-feedback configuration, thus virtual ground, but none of that beautiful op-amp action is seen at amp B :(

I'm thinking the second amp is bogus as it's totally shorted to ground and bypassed straight to the ADC; could potentially release some really nice magic smoke. Inputs would be fine, though!

Pic: Op amps configured in the weird configuration listed above https://wiki.jlab.org/cuawiki/images/d/d9/CW-Base_Jan2016_v2.pdf

Any feedback helps!

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The schematic doesn't match the layout.

I overlaid the PCB sides and highlighted the connections to pin 5 of the TL062 in black. This shows that pin 5 is actually connected to ground, and pin 7 is the output to the Arduino.

enter image description here

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As Bruce Abbott points out, the pin connections on U1B are incorrect. U1B is a simple inverter with a gain of 1 (but very high accuracy.)

Basically, resistor divider chain at the top of the schematic reduces the (negative) cathode voltage to a reasonable value. U1A buffers the divider, and U1B inverts the voltage so as to feed the ADC with a positive voltage.

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