Abstract-This paper reviews the concepts, opportunities and limitations of temperature sensors and voltage references realized in CMOS technology. It is shown that bipolar substrate transistors are very suited to be applied to generate the basic and PTAT voltages. Furthermore, it is shown that dynamic element matching and auto-calibration can solve the problems related to mismatching of components and 1 noise. The effects of mechanical stress are a major source of inaccuracy. In CMOS technology, the mechanical-stress effects are small, as compared to those in bipolar technology. It is concluded that, with low-cost CMOS technolog, rather accurate voltage references and temperature sensors can be realized.

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This paper describes the design of a precision BJT-based temperature sensor implemented in standard 0.7µm CMOS technology. It employs substrate PNPs as sensing elements, which makes it insensitive to the effects of mechanical (packaging) stress and facilitates the use of low-cost packaging technologies. The sensor outputs a duty-cycle-modulated signal, which can easily be interfaced to the digital world and, after low-pass filtering, to the analog world. In order to eliminate errors caused by component mismatch, chopping and Dynamic Element Matching (DEM) techniques have been applied. The required component shuffling was done concurrently rather than sequentially, resulting in a fast DEM scheme that saves energy without degrading accuracy. After a single-temperature trim, the sensor's inaccuracy is ±0.1ºC (-20ºC to 60ºC) and ±0.3ºC (-45ºC to 130ºC), respectively. Measurements of sensors in different packages show that the package-induced shift is less than 0.1ºC. Measurements of 8 sensors over 367 days show that their output drift is less than 6mK. While dissipating only 200µW, the sensor achieves a resolution of 3mK (rms) in a 1.8ms measurement time, and a state-of-the-art resolution Figure of Merit (FoM) of 3.2pJK 2. This combination of high accuracy, high resolution, high speed and low energy consumption makes this sensor suited for commercial and industrial applications.

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Saponin extracted from Patrinia villosa (Thunb.) Juss (SPVJ) is a Chinese medicine which is used widely by traditional medicine doctors. In this study, the antitumor effects and the possible mechanisms of SPVJ were investigated in mice bearing U14 cervical cancer. The results showed that SPVJ (50 mg/kg and 100 mg/kg) effectively reduced the weight of U14 cervical tumor (35.1% and 57.1%, respectively). Compared with the control group, SPVJ (100 mg/kg) significantly increased tumor cells in the G0/G1 phase (38.1% vs 68.5%), increased the number of cells in apoptosis (9.4% vs 28.9%) and G0/G1 phase and decreased the number of cells in S phase (41% vs 26.2%) and G2/M (20.9% vs 5.3%), inhibited proliferating cell nuclear antigen (PCNA) of tumor cell (80.6% vs 21.8%), decreased the expression of mutant p53 (66.4% vs 33.5%) and bcl-2 protein (78.2% vs 20.3%). The mechanism of the SPVJ antitumor effect might be associated with inhibition of tumor cells in G0/G1 phase, inducing apoptosis and inhibiting the expression of PCNA, mutant P53 and Bcl-2 protein.