This document introduces Circuit Note CN-0240 Circuits from the Lab™ reference circuits, which are designed to solve analog, mixed-signal, and RF design challenges. The products mentioned in the document include AD629 High Common-Mode Voltage Difference Amplifier, AD8622 Precision, Low Noise, CMOS, Dual, Rail-to-Rail Output Op Amp, AD8475 Precision, Selectable Gain, Fully Differential Funnel Amplifier, etc.