Hey all, This newb needs help understanding the posted circuit. Real quick, I'm going to post what I understand from left to right. R53 and R62 = Voltage Divider D2 = Clamping Diode (Clamping to 3.3V) R45 = R1 in basic (R2/R1)Vin = Vout op amp formula This is where I get stuck. Let's call the node b4 R45 Vin. We would have [(Vin-Vref)/R45] = [(Vref - Vo)/R2] - however no R2. Instead, there's a diode that is in the off (depending on how you look at it) preventing any output from the first op-amp. Where then I guess the second OP Amp equation looks like Vo = [(Vin-Vref)/R45]. I am pretty sure I am missing some inverse logic in all of this, but regardless, I hope I got what I was trying to say across. Click Here for the Op-Amp datasheet. Any help would be greatly appreciated. Namely, what is that diode doing? What's the purpose of this circuit? Thank you.