From the ADL 5566 Datasheet, i see that there are two outputs VON1 and VOP1 for amplifier 1. If this is a differential amplifier, what are the outputs at VON1 and VOP1 in terms of input. How do i get an output which is the difference between the two input voltages. Also, i see a small bubble at the top of the first op-amp. What is the significance of that bubble?