This chapter describes the realization of three CMOS smart temperature sensors in which the techniques introduced in the previous chapters have been applied. The first two sensors are continuous-time designs in which the most dominant errors–spread and curvature of the base-emitter voltage, and amplifier offset–have been addressed. These sensors have been implemented in a 0.7
m and 0.5
m digital CMOS process and achieve an inaccuracy of ±1.5 °C and ±0.5 °C, respectively. The third sensor is a switched-capacitor design in which many more dynamic error correction techniques have been applied. This design will therefore be described in most detail. It has been implemented in a 0.7
m CMOS process and has an inaccuracy of ±0.1 °C. A comparison with previous work, included at the end of the chapter, shows that this is, to date, the highest reported accuracy.