Noise-sensitive applications need ultra-low noise LDO regulators

摘要

Linear Regulators are integrated circuits that step a voltage down without the need of an inductor. The low dropout (LDO) linear regulator is a special type of regulator with a dropout voltage (the differential between input-to-output voltages needed to maintain regulation) typically below 400mV. Early linear regulator designs offered dropouts in the order of ~ 1.3V (meaning for a 5V input, the maximum achievable output was only ~3.7V for the device to stay in regulation). More recently, "low" dropout is considered to be 500mV or less - and in these days of more sophisticated design techniques and wafer fabrication processes, is typically between <100 to 300mV.