单晶体管 46dB 通过减少 LDO 噪音Maxim > App Notes > AMPLIFIER AND COMPARATOR CIRCUITS POWER-SUPPLY CIRCUITS Keywords: Low-dropout regulator, LDO, RC filter Nov 23, 2005 APPLICATION NOTE 3656 Single Transistor Reduces LDO Noise by 46dB Abstract: A simple RC filter with an external transistor driver rejects LDO noise. A plot of noise density vs. frequency shows that the filter rejects LDO noise by more than 46dB, and achieves a noise floor of 7nV/ . Of the many low-dropout (LDO) regulators providing voltage regulation for electronic systems, some are specifically designed for low noise. The voltage regulator in Figure 1, for example, achieves an RMS noise voltage of about 115V. Some ultra-low-noise applications such as instrumentation and high-qualit……