Summary: | 碩士 === 國立中正大學 === 電機工程研究所 === 100 === This thesis presents an integrated Low Dropout (LDO) voltage regulator design which is suitable for low-voltage, low-power and high-performance system on a chip (SOC) application. Using the 1-V TSMC 90nm CMOS process, the proposed LDO voltage regulator can convert an input voltage of 1V to an output voltage of 0.85V-0.5V by adjusting the resistance of feedback network. With the requirement of power supply quality in low-voltage system, the proposed LDO voltage regulator have to achieve high Power Supply Rejection Ratio (PSRR) and fast transient response. First power noise isolation and ripple cancellation techniques are proposed to improve the PSRR of LDO voltage regulator effectively. Furthermore, a slew-rate enhancement circuit is applied to enhance the transient response. Simulation results show that at least -50dB PSRR is achieved at 0-1MHz for a load range of 0-100mA, while the output voltage variation is less than ± 3% of output voltage to ensure the power supply quality and performance of the load circuit. The current efficiency of the proposed LDO voltage regulator is 99.91%.
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