This document introduces the CN-0338 Circuits from the Lab® reference design, which is engineered and tested to solve analog, mixed-signal, and RF design challenges. The document lists several devices, including zero-drift operational amplifiers, precision amplifiers, low-noise LDO regulators, and low-power microcontrollers.
The document details the Analog Devices CN-0338 reference design, which is an NDIR-based gas detection circuit optimized for carbon dioxide (CO2) sensing. The system utilizes a thermopile sensor and is engineered to be compatible with Arduino-compatible platforms via a specific shield board.
The design employs key components including the ADuCM360 microcontroller for processing, the AD8629 operational amplifier for low-noise signal conditioning, and the ADA4528-1 as a buffer. The circuit operates by measuring the temperature difference between active junctions heated by infrared light and reference junctions to determine gas concentration based on absorption spectra.
The circuit is optimized for carbon dioxide (CO2) detection.
The thermopile output voltage ranges from a few hundred microvolts to a few millivolts.
The thermopile source impedance may be around 100 kΩ.