I am trying to implement common mode feedback circuit for 2 stage amplifier. I swept length of transistor using variable "lcmfb" vs DC voltage of node "VOUT+". I sweep it using ADE L dc analysis with linear 10n step size. The graph shows that at lcmfb = 2u, the VOUT+ DC value is 880mV. But when I set lcmfb value to 2u, the resulting voltage is 1.8V instead of 880mV. Why the value is different from Viva XL Graph? For more information, the VOUT+ is fed back into input (negative feedback) at a higher level schematic. I can't upload the image directly so here is the link to the image. https://imgur.com/a/XLA1hEu (Left: Node voltage on schematic, Middle: Viva XL Graph from DC Sweep, Right: ADE L interface, lcmfb = 2u)
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