The document introduces the reference circuits of Circuit Note CN-0213 Circuits from the Lab™, which are engineered and tested to help solve analog, mixed-signal, and RF design challenges. The devices connected/referenced in the document include AD7685 16-Bit, 250 kSPS PulSAR® ADC in MSOP/QFN, AD8226 Wide Supply Range, Rail-to-Rail Output Instrumentation Amplifier, AD8275 G = 0.2, Level Translation, 16-Bit ADC Driver, ADP1720 50 mA, High Voltage, Micropower Linear Regulator, and ADR439 Ultralow Noise XFET® Voltage Reference. The document also mentions that these circuits have been designed and built by Analog Devices engineers and tested and verified in a lab environment. However, users are responsible for testing the circuit and determining its suitability and applicability for their own use and application.