The following presentation describes is a case study for a battery powered, wearable device that monitors air quality, humidity, light and temperature. These phenomena are all slow changing and therefore do not require high bandwidth or a fast ADC sample rate. When these items are sampled, it is critical that precision measurements are performed. Additionally the sensors are passive devices which require biasing and have high output impedance therefore analog performance of the interface circuits is very specific.

These requirements place a unique set of constraints on the application which leads to an arduous process for selecting catalog IC’s that simultaneously meet all performance criteria and still remains in the target cost range. Alternatively, through specification of a custom rASIC, resources can be custom designed and tuned specifically for these requirements.

In this presentation, we will walk through the buildup of this Low Power ASIC.