A highly sensitive weak current detection circuit for implantable glucose monitoring is presented. The circuit consists of a current splitter, an integrator, a sampling/holding (S/H) circuit, and an 8-bit successive approximation register (SAR) analog-to-digital convertor (ADC). T-switches, source voltage shifting and correlated double sampling (CDS) technology are adopted to reduce the effects of leakage currents, charge injection, dc offset and low-frequency 1/f noise. The work range is divided into 5 sub-ranges to reduce the complexity and power consumption of current detection. The chip was fabricated with 0.13 µm CMOS technology. Test results show that the circuit can detect weak signal from 10 fA to 1 nA with 1.5 V supply and 7.2 µW power consumption. The tested leakage current of the design is 4 fA.

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The swift heavy ion irradiation effect on bilayer graphene is investigated. The radial dose distributions of delta rays produced by bismuth ions are calculated by Monte Carlo method. The radial dose rapidly decreases with increasing the distance from the track center. The energy deposited into the lattice due to electron-phonon coupling is simulated by molecular dynamics method. By given energy to a cylindrical region, the stress accumulates in this area. And then, a pressure wave emanates outwards, which leads to the atoms in the thermal spike region escaping from the upper and lower surface in the form of clusters. As a consequence, the defect configuration is composed of a central pore with radius larger than 0.5 nm and surrounding carbon chain loops.

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A modified pulse-coupled spiking neuron circuit (MPSNC) with memory threshold is presented. It is constructed with two single modified spiking neuron circuits (MSNCs). In MPSNC, one MSNC stores the potential of its threshold signal at the latest firing time of another MSNC as threshold, implying a short-term cross memory. We extend the definition of least common multiple to obtain the firing phase of MPSNC. By studying the iterative map of firing time and firing phase, the dynamics and statistics are revealed. The chaotic map of firing phase is applied to image encryption. Besides, the hardware circuit and simulation are built.

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In aerospace environment, single event effect (SEE) will occur and single event transient (SET) current pulse will be induced in drain/source region of Metal Oxide Semiconductor Field Effect Transistor (MOSFET) when high energy ion strikes semiconductor devices. The typical double exponential transient current model proposed for traditional technology is not suitable for ultra deep sub-micron technology devices. In this paper, a novel multi-dimensional double exponential transient current model is proposed based on our new understanding of ultra deep sub-micron radiation mechanism, which has been validated using Technology Computer Aided Design (TCAD) simulation. This model can be important basis for the searching of SEE at circuit level and can be transparently applied to evaluate the effectiveness and performance of hardening technique, thus shortening the developing cycle of integrated circuit intended to operate within aerospace environment.

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8T SRAM have been considered for robust subthreshold SRAM design. Their subthreshold operation was successfully demonstrated through real silicon measurements. However, Monte-Carlo simulation results show that this SRAM still may not deliver sufficient reliability in subthreshold operation. In this work, we overcome this problem by properly sizing SRAM transistors. We utilize short-channel V_t roll-off and inverse narrow-width effect for the sizing. Since minimum geometry transistors are employed in the SRAM bit-cell, these effects can have profound impact on SRAM stability. Hence, the proposed approach provides an efficient way to increase the yield of the 8T subthreshold SRAMs.

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Wide voltage range circuit has got widespread attention where in-situ timing monitoring based adaptive voltage scaling (AVS) becomes necessary to reduce the design margin. However, the severe PVT variations across near-threshold to super-threshold cause too many critical paths to be monitored. Here activation oriented monitoring paths selection method is proposed to reduce the monitored paths for wide voltage IC. The minimum delay value of the longest activated path is found by dynamic timing analysis and set as the selection threshold. Those paths longer than this threshold by STA analysis are selected to be monitored. Applied on a 40 nm AVS System-on-Chip, it reduces the monitoring paths to only 22% of all critical paths with remarkable power gains under 0.6 V–1.1 V.

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In this paper we propose a new single-phase sag compensator intended for transformer-coupled loads that integrates a current-controlled inverter in parallel with the secondary winding of an isolation transformer. Compared with conventional single-phase series-voltage sag compensators that produce a high inrush current during the starting of the compensation process, the proposed sag compensator eliminates the inrush current and achieves seamless compensation for the load current. The performance of the proposed sag compensator is validated by our experimental results for a small prototype.

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This paper presents a new area-efficient and fast sampling multiplexer for battery monitor system. This multiplexer structure introduces a full differential leapfrog sampling scheme which leads to half of occupied area, less sampling time and higher common mode rejection rate (CMRR) than the traditional one. This kind of multiplexer structure was introduced in a 12-ch battery monitor IC which fabricated with 60 V BCD process. The measurement result shows that the presented multiplexer achieves a channel mismatch error up to 1.2 mV (Typical) while the battery monitor IC works in 400 ns sampling time.

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In this paper, a fast li-ion battery charger microcontroller (MCU) based on configurable pulse width modulation (PWM) controller by tracking the polarization curve of battery cells is proposed in order to inject the maximum charge-current without battery degradation and its fully custom-designed MCU is implemented as a system-on-chip (SoC) using 0.18 um Embedded Flash CMOS process. The evaluation results show that a newly designed charger is about 18.6% faster than the conventional constant-current (CC) charging method with the temperature rise within a reasonable range. The implemented charger system by tracking the battery cell polarization curve results in charging 4 cells of battery to about 80% of its maximum capacity in less than 56 minutes and 13°C maximum temperature rise without damaging the battery.

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Resolution of live electrooptic imaging (LEI) having an ultimately-thinned (10-µm) electrooptic sensor plate has been evaluated experimentally and discussed theoretically. The evaluated resolution value is 30–40 µm, which is the best ever demonstrated for the LEI technique. Through its theoretical analyses, the following three resolution-limiting factors have been quantified and a guideline for resolution improvement has been discussed; (a) the image sensor pixel density, (b) the magnification and resolution of the laser optics, and (c) the electrooptic sensitive volume.

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A novel substrate integrated waveguide (SIW) power divider with good out-of-band rejection and isolation is first presented in this paper, which is implemented by the combination of three different electromagnetic structures, saying, substrate integrated waveguide (SIW), defected ground structure (DGS) and resistive coupling slot. Since the SIW has high-pass performance and the DGS has band-stop characteristics, four periodic butterfly-shaped DGS are etched on the ground plane of the SIW power divider to realize the band-pass filtering response. Moreover, a resistive coupling slot is utilized to improve the isolation of power divider. To verify the design, a prototype of the SIW power divider is fabricated and measured. Measured results show that a very wide out-of-band rejection ranging from 13.5 to 22 GHz at −20 dB is realized. The isolation, input return loss, output return loss, amplitude imbalance, and phase imbalance of the in-phase SIW power divider are better than 15.3, 14.1, 9.2, 0.5 dB, and 5.1°, respectively, within the frequency range from 8.25 to 12.25 GHz. The measurement results show good agreements with the simulation ones.

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A simple circuit is introduced in this paper for eliminating power dissipation of bleeder resistor when the power converter is plugged to the power outlet. The depletion-type NMOS device can be naturally turned-on to establish discharge path of X capacitor without driving voltage for safety consideration. And the depletion-type NMOS device is virtually turned off to disconnect bleeder resistor for improving the efficiency of power converter while AC power is on. As a result, the waste power can be removed in normal operation, light load, especially in standby load conditions for comply the newest energy star specification, EuP lot 6 and 5 star standards of mobile charger standby power regulations. Experimental results demonstrate that the proposed scheme can implement ultra low standby power of converter with a simple and low cost solution.

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A kind of Wilkinson power divider with bandpass filtering response is presented in this letter. In the proposed power divider, two bandpass filters are used to substitute two quarter-wavelength transformer in a conventional Wilkinson power divider. This kind of Wilkinson power divider has two transmission zeros out of the passband. One transmission zero is created by the dual mode resonator intrinsic characteristics. The other is introduced by the source-load coupling. Different transmission zeros could be achieved by changing the dimension of the dual mode resonator or the source-loading coupling. Two experimental circuits are fabricated by the traditional printed circuit board technology. The measured and simulated results are in good agreement.

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Coaxial through silicon via (TSV) is a promising technology in three dimensional integrated circuits (3D ICs). Conventional coaxial TSV offers shield around part of the TSV in silicon substrate leave the two ends of TSV and the whole pad without any shield. This paper reports a new coaxial TSV, which offers more shields around TSV and pad with gaps for interconnection. Furthermore, the new structure is more feasible by using double dielectrics with considering deformation and process error. The full-wave extraction simulation result shows that the new structure offers less coupling with adjacent TSVs than conventional coaxial TSV structure does. The losses of new structure is lager but can be reduced by increasing the thickness of gap.

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The influence of nonlocal effects has been investigated for the metallic nano chain constructed of Au cylinders straightly arranged in one direction. The chain has two-unique propagation modes, longitudinal and transverse ones, and our investigation for the nonlocal effects has been made especially in terms of those. Obtained results clarify the relationships between the influence of the effects and the arranged cylinders characterized by the smallness and adjacency which deeply affect to also the propagation property of the two modes.

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