27.8 Fully integrated optical spectrometer with 500-to-830nm range in 65nm CMOS

Next-generation IoT systems are expected to be enabled by compact, low-cost, low-power, smart sensing devices that provide a wealth of information to build new applications and capabilities. Among sensing modalities, optical spectrometry is one of the rapidly growing areas of interest due to its wide range of applications from environment monitoring, industrial and home applications to healthcare [1-3]. As shown in Fig. 27.8.1, current optical spectrometers are large and bulky with non-integrated components that limit their application potential. In this paper, we present a fully integrated CMOS-based optical spectrometer in a 65nm bulk process that requires no external optical components. The spectrometer achieves nearly 10nm resolution and 1.4nm accuracy in peak prediction of continuous-wave (CW) excitations between 500 and 830nm.