Analog front-end for precise human body temperature measurement

Analog front-end for precise temperature measurement of a human body has been presented. The discussed analog front-end (AFE) contains a new temperature calibration technique based on on-chip resistor. The described calibration method allows to obtain very high accuracy, even 0.1 °C, in very wide range of an operating temperature of an integrated circuit. The AFE consists of a bandgap current reference, a precision current source, a programmable gain amplifier, a voltage source proportional to absolute temperature and on-chip temperature calibration resistor. The presented analog front-end consumes no more than 180 uW and was designed and manufactured in UMC CMOS 130 nm technology. All data presented in the article were obtained from measurements. Measurements were taken using manual wafer prober with climate control microchamber, at temperature range from −40 °C to 125 °C.