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This paper aims to propose a low-power complementary MOS (CMOS) current sensor for control circuit in an integrated DC-DC buck converter.

The integrated DC-DC converter, which is composed of feedback control circuit and power block, is designed with 0.35-µm CMOS process. Current sensor in the control circuit is integrated with sense-FET and voltage-follower circuits to reduce power consumption and improve its sensing accuracy. In the current-sensing circuit, the size ratio of the power metal oxide semiconductor field effect transistor (MOSFET) to the sensing transistor (K) is 1,000, and a current-mirror is used for a voltage follower. N-channel MOS acts as a switching device in the current-sensing circuit, where the sensing FET is in parallel with the power MOSFET. The amplifier and comparator are designed to obtain a high gain and a fast transient time.

Experiment shows that the current sensor is operated with accuracy of more than 85 per cent, and the transient time of the error amplifier is controlled within 100 µs. The sensing current is in the range of a few hundred µA at a frequency of 0.6-2 MHz and an input voltage of 3-5 V. The output voltage is obtained as expected with the ripple ratio within 5 per cent.

The proposed current sensor in DC-DC converter provides an accurately sensed inductor current with a significant reduction in power consumption in the range of 0.2 mW. High-accuracy regulation is obtained using the proposed current sensor. As the sensor utilizes simple switch-type voltage follower and sense-FET, it can be widely applied to other low-power applications such as high-frequency oscillator and over-current protection circuit.

The purpose of this paper is to present a fully integrated power converter. A stacked spiral inductor is applied in a voltage‐mode CMOS DC‐DC converter for the chip miniaturization and low‐power operation.

The three‐layer spiral inductor is simulated with an equivalent circuit and applied to the DC‐DC converter. The DC‐DC buck converter has been fabricated with a standard 0.35 μm CMOS process. The power converter is measured in both experiment and simulation in terms of frequency and electrical characteristics.

Experimental results show that the converter with the stacked spiral inductor operates properly with the inductance of 7.6 nH and mW power range. The measured inductance of the stacked spiral inductor is found to be almost half of the circuit designed value because of the parasitic resistances and capacitances in the spiral inductor.

This paper first introduces the application of the integrated stacked spiral inductor in DC‐DC buck converter for display driver circuit, which requires a low‐power operation. It also shows the fully integrated DC‐DC converter for chip miniaturization.

Students with special needs include children with impaired attention, disruptive behavior, learning disabilities, and developmental disorders, among many other conditions. When a child has been diagnosed with such a disorder, his or her parents may seek treatment that could assist the child to be more academically and socially successful. Numerous interventions exist for the treatment of childhood disorders; however, these treatment methods differ in the types and amounts of evidence supporting their usefulness and effectiveness (Lilienfeld, 2005).

This article deals with Virtual Singapores, or Singapore’s efforts to clone itself through industrial parks in Asia’s developing countries. Through these cloned enclaves, tiny Singapore aims to control change and restructuring in Asian economic environments, and thereby its own destiny. The first section elaborates on Singapore’s regionalisation drive and Virtual Singapores. The ensuing section identifies the strategic goals for internationalizing Singapore Incorporated, the alliance of stakeholders that guides governmental policy in Singapore. The final section discusses the implications of the Virtual Singapores for competitive environments, as well as for organizational and structural changes in the Asia Pacific.

Quantitative reliability analysis can effectively identify the time the driving system needs to be maintained. Then, the potential safety problems can be found, and some catastrophic failures can be effectively prevented. Therefore, this paper aims to evaluate the reliability of the switched reluctance generator (SRG) driving system.

In this paper, a method considering different thermal stresses and fault tolerance capacity is proposed to analyze the reliability of an SRG. A full-bridge power converter (FBPC) instead of the asymmetric half-bridge power converter (AHBPC) is adopted to drive the SRG system. First, the primary fault modes of the SRG system are introduced, and a fault criterion is proposed to determine whether the system fails. Second, the thermal circuit model of the converter is established to quickly and accurately obtain the junction temperature of the devices. At last, the Markov models of different levels are established to evaluate the reliability of the system.

The results show that the two-level Markov model is the most suitable when compared to the static model and the one-level Markov model.

The driving system of SRG will be more reliable after the reliability of the system is evaluated by the Markov model. At the same time, an FBPC is adopted to drive the SRG. The FBPCs have the advantages of fewer switching devices, higher integration and lower cost. The proposed driving strategy of the FBPC avoids the current reversal and the generation of dead zone time, which has the advantage of reliable operation. In addition, a precise thermal circuit model of the FBPC is proposed, and the junction temperature of each device can be obtained, respectively.