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Stretching experiments on lambda-deoxyribonucleic acid (DNA) were carried out in microfluidic channel using a microscope, micro-flow pump, and electromagnet. The micro-flow channel was fabricated by using micro electromechanical technology, and the electromagnet was analyzed by software to simulate the magnetic field distribution. The magnetic field was 248.6 gauss at a current of 0.5 A, and the system could exert 20.4 pN of force on a magnetic bead with diameter of 2.8 µm. When the buffer temperature was 25 °C, the average length of lambda-DNA molecules was 1.9 µm without magnetic field. In a magnetic field of 248.6 gauss, the extension was 7.2 µm, the total length was 9.1 µm, and the coefficient of elasticity was 2.83 x 10-6 N/m. When the buffer temperature was 45 °C, the average length was 4.6 µm without magnetic field. At 45 °C in a magnetic field of 248.6 gauss, the extension was 11.9 µm, the total length was 16.5 µm, and the coefficient of elasticity was 1.71 x 10-6 N/m. Besides, the denature temperature of dsDNA decreases with increasing magnetic force, and the temperature difference can be higher than 7 °C. This system can be used to measure the related properties of macromolecules. [ABSTRACT FROM AUTHOR]

This paper proposes a time-domain CMOS smart temperature sensor featuring on-chip curvature correction and one-point calibration support for thermal management systems. Time-domain inverter- based temperature sensors, which exhibit the advantages of low power and low cost, have been proposed for on-chip thermal monitoring. However, the curvature is large for the thermal transfer curve, which substantially affects the accuracy as the temperature range increases. Another problem is that the inverter is sensitive to process variations, resulting in difficulty for the sensors to achieve an acceptable accuracy for one-point calibration. To overcome these two problems, a temperature- dependent oscillator with curvature correction is proposed to increase the linearity of the oscillatory width, thereby resolving the drawback caused by a costly off-chip second-order master curve fitting. For one-point calibration support, an adjustable-gain time amplifier was adopted to eliminate the effect of process variations, with the assistance of a calibration circuit. The proposed circuit occupied a small area of 0.073 mm2 and was fabricated in a TSMC CMOS 0.35-μm 2P4M digital process. The linearization of the oscillator and the effect cancellation of process variations enabled the sensor, which featured a fixed resolution of 0.049 °C/LSB, to achieve an optimal inaccuracy of -0.8 °C to 1.2°C after one-point calibration of 12 test chips from -40 °C to 120 °C. The power consumption was 35 μW at a sample rate of 10 samples/s.C. The power consumption was 35 μW at a sample rate of 10 samples/s.C to 120 °C. The power consumption was 35 μW at a sample rate of 10 samples/s. [ABSTRACT FROM AUTHOR]