Xuecheng Zou

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Ion implantation, followed by annealing process, often leads to nonuniform doping and considerable depletion effect in the polysilicon gate of submicron MOS devices. Such an effect can alter notably the subthreshold characteristics and invalidate the conventional subthreshold current model. This paper studies the polysilicon-gate depletion effects on the(More)
—For a sensorless predictive-peak-current-controlled boost converter, the output voltage steady-state error cannot be eliminated by voltage loop PI controller. The basic cause for this is investigated through analysis and theoretical approaches. To eliminate the voltage steady-state error and achieve high-accuracy current estimation, a comprehensive(More)
In digital current mode controlled DC-DC converters, conventional current sensors might not provide isolation at a minimized price, power loss and size. Therefore, a current observer which can be realized based on the digital circuit itself, is a possible substitute. However, the observed current may diverge due to the parasitic resistors and the forward(More)
—A precise bandgap reference with intrinsic compensation for current-mirror mismatch is presented. In the proposed circuit, the small-signal current variations in the two current paths are self-compensated while in the conventional bandgap core they are multiplied. As a result, error caused by current-mirror mismatch has been much reduced in the proposed(More)
A RF powering circuit used in radio-frequency identification (RFID) tags and other batteryless embedded devices is presented in this paper. The RF powering circuit harvests energy from electromagnetic waves and converts the RF energy to a stable voltage source. Analysis of a NMOS gate-cross connected bridge rectifier is conducted to demonstrate relationship(More)