A Wide Input Range LDO with Floating Ground Output

In this paper, for the problem of unstable ground and wide input voltage range in automotive electronic system, a wide input range LDO with floating ground output based on 0.5um SOI process is proposed. Unlike the traditional LDO, the power transistor of this design adopts the high-voltage NMOS, and the output is adjusted through voltage sampling and the negative feedback loop. The design achieves constant voltage output relative to the power supply and widens the input voltage range. Simulation results show that the input voltage range of the designed LDO can reach 5.5-65V. The line regulation can reach 0.004mV/V and PSRR at 100Hz is 81.6dB.