In this paper, we propose a two-dimensional (2D) analytic model for the channel potential and electric field distribution of the RESURF AlGaN/GaN high electron mobility transistors (HEMTs). The model is constructed by two-dimensional Poisson's equation with appropriate boundary conditions. In the RESURF AlGaN/GaN HEMTs, we utilize the RESURF effect generated by doped negative charge in the AlGaN layer and introduce new electric field peaks in the device channels, thus, homogenizing the distribution of electric field in channel and improving the breakdown voltage of the device. In order to reveal the influence of doped negative charge on the electric field distribution, we demonstrate in detail the influences of the charge doping density and doping position on the potential and electric field distribution of the RESURF AlGaN/GaN HEMTs with double low density drain (LDD). The validity of the model is verified by comparing the results obtained from the analytical model with the simulation results from the ISE software. This analysis method gives a physical insight into the mechanism of the AlGaN/GaN HEMTs and provides reference to modeling other AlGaN/GaN HEMTs device.

A 500–600 MHz high-efficiency, high-power GaN power amplifier is designed and realized on the basis of the push-pull structure. The RC–LC stability network is proposed and applied to the power amplifier circuit for the first time. The RC–LC stability network can significantly reduce the high gain out the band, which eliminates the instability of the power amplifier circuit. The developed power amplifier exhibits 58.5 dBm (700 W) output power with a 17 dB gain and 85% PAE at 500–600 MHz, 300 μs, 20% duty cycle. It has the highest PAE in P-band among the products at home and abroad.

Abstract-In recent years, the screen size and backlight brightness have been increased year by year in portable electronic equipment, which makes much more requirements for LED driver chips. A 3-channel boost LED driver with high efficiency is proposed, and it has 3 channels with 10 LED lights in each channel. The current flow in each channel can reach to 20mA. In order to improve the output efficiency of the chip, the on-resistance of the power MOS sampling method is used here. Thus can achieve powerless sampling. Direct PWM control method is used in the circuit to complete the dimming, which can achieve colorless output of the white light. The use of a dimming MOSFET and LDO in the circuit to further optimize the power consumption. The circuit is designed and simulated in CSMS 0.25um BCD technology. The input voltage range is 2.7V~5V. The maximum dimming output voltage is 36V. The final output efficiency of the chip can achieve 91.4%.The rising time of the LED current in the dimming circuit is about 192ns and the falling time is about 14ns. The maximum dimming ratio is 9000: 1 at 500Hz.

No abstract

Abstract.A P-band high-efficiency, high power GaN power amplifier is designed and relized on the basis of the push-pull structure. The LRC-LC stability network is proposed and applied to the power amplifier circuit for the first time. The LRC-LC stability network can significantly reduce the high gain out the band, which eliminate the instability of the power amplifier circuit. The developed power amplifier exhibits 58.5dBm (700W) power output with a 17dB gain and 85% PAE at 500-600MHz, 300us, 20% duty cycle. It has the highest PAE in P-band among the products at home and abroad.