This paper presents a design solution for measuring the ratio between different capacitors available in common integrated technology (i.e. MIM, MOM, poly-poly, etc.) by using a Charge Pump (CP) and a system solution approach that defines an alternative self-test operating mode at zero extra die are and cost. Relying on the charge sharing principle, the proposed approach involves two symmetrical structures working in phase opposition and it has been designed in a standard 180-nm CMOS technology. In each of this structure, MIM and MOM capacitors are connected so that, during standard DC-DC boost converter operating mode of the CP, clock pumps result from a sum of the charges coming from both capacitors. During capacitance ratio read out phase, half CP is inhibited while a digital logic controls the initial fly capacitor to be used which determines the amplitude of the first pump. By evaluating it through an input analog chain and repeating this process for the other side, measurements with accuracy of 200ppm over 1% of capacitive variation due to aging or stress effects are reported, regardless the value of the external load.

This paper presents a non-imaging differential digital passive Infra-Red (PIR) remote sensing system using CMOS-SOI-MEMS transistors as the thermal sensor. A large $660\mu {\mathrm m}\, {\mathrm x}\, 660\mu{\mathrm m}$ pixel area is developed by the 8x8 mosaic matrix of $60\mu {\mathrm m} \,{\mathrm x}\, 60\mu{\mathrm m}$ sub-pixels connected in-parallel. The mosaic sensors, which are manufactured by nano-fabrication methods in CMOS FABs, exhibit enhanced performance and robust manufacturing in wafer level processing and vacuum packaging. Since the sub-pixels are thermally isolated, the thermal time constant of the large pixel is determined by that of the sub-pixel, which is $\sim {\mathrm 80}$ msec when packaged in vacuum of $\sim 1{\mathrm Pa}$. For outdoor operation, two identical large pixels are differentially measured. The pixels view the detected scene with an optics that may be based either on mirror optics or Fresnel plastic lenses. The optics defines a narrow field of view (± 3 degrees) as required for curtain sensors. Furthermore, the optics forms “cockeyed” vision which enables differential measurement that cancels the environmental” noise” and allows outdoor operation. The overall measured performance for detecting human targets at extended ranges and hot spots detection are reported. This sensor outperforms thermopiles and pyroelectric sensors at outdoor operation.

This paper presents a novel micromachined high-responsivity thermopile sensor, fully compatible with standard CMOS-SOI (Silicon-On-Insulator) processes. The proposed thermopile features a versatile mosaic structure, based on 128 60 μ m × 60 μ m pixels connected in series and/or in parallel. Two versions of the proposed thermopile sensor, featuring a different number of equivalent pixels, are presented and fully characterized. The most performing of the two features $2.9\cdot 10^{4}\frac{V}{W}$-responsivity, outperforming other state-of-the-art thermopile sensors. The application of the most performing thermopile as proximity and motion detector was also verified through measurements.

This paper presents a fully integrated CMOS contactless temperature sensor. The sensing element is a CMOS compatible thermopyle sensor, which consists of polysilicon resistors with different doping in a suspended membrane to increase their thermal resistance and sensitivity. The output signal of the thermopyle is fed into a high impedance programmable gain amplifier (PGA) and digitized by an energy-efficient voltage-to-digital converter based on a second-order delta-sigma modulator ($\Delta\Sigma$). This $\Delta\Sigma$ employs a first stage low noise integrator, a feedforward to reduce input swing on the second stage integrator, and scrambling of the input capacitors to reduce mismatch errors. The $\Delta\Sigma$ also converts the die temperature sensor used to read the absolute temperature of the radiating object. The proposed contactless temperature sensor has been realized with 130-nm CMOS process with nominal supply voltage at 1. 8V. A power consumption of approximately 3.6 $\mu$W has been recorded from measurements, while an equivalent Object temperature rms noise of 30 mdegC can be achieved, rendering the circuit suitable for portable and wearable applications.

This paper presents a microsystem suitable for contact-less human body temperature measurements, as well as for presence, motion and proximity detection. It consists of a 130-nm CMOS-SOI MEMS (Micro-Electro Mechanical System) thermal sensor, referred to as “TMOS”, and its 130-nm CMOS interface circuit. The TMOS, based on a micromachined transistor, being an active device, features advantages in terms of internal gain: with optimal biasing, indeed, the TMOS achieves 274-$\mu \text{V}/^\circ \text{C}$input-referred sensitivity at 3-cm distance and 50.33° field-of-view (FOV), outperforming thermopile detectors. The sensor and the interface circuit, featuring a chopper-stabilized-based analog readout with a 12-bit SAR ADC (Successive Approximation Register Analog-to-Digital Converter), were mounted in the same package and extensively measured: the microsystem achieves repeatability and ±0.17°C precision, thus satisfying the requirements for contact-less human body temperature measurements; furthermore, its performance as presence, motion and proximity detector was also verified.

This paper presents a readout circuit for thermopile-based thermal sensors, suitable for contactless temperature measurements. The circuit, designed and extensively simulated in a standard 130-nm CMOS process, employs chopper stabilization in order to minimize offset and noise contributions at low frequency, while providing proper amplification to the input signal, which behaves substantially as a DC. The circuit nominal supply voltage is 1.2 V and its power consumption is approximately 260 μW. The proposed single-ended architecture solves the drawbacks of the most straightforward fully differential approach, while achieving a simulated input-referred residual offset mean value equal to 84.4 nV, with 487 nV of standard deviation. An accuracy of ±0.3°C is provided at room temperature, making the circuit suitable for medical devices, such as contactless fever thermometers, and security systems, such as motion and human presence detection sensors.