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Figure 1: The challenge of dynamic performance vs. current consumption has been addressed by introducing parts that are switchable between low power mode and high performance. A typical example is ON Semiconductor's NCP4587.
Looking at products that are currently sampling, it appears that products with noise in the 10 ?VRMS range and Quiescent current in the 10-15 μA range will be in production by the end of this year, giving cell phone designers the best of both worlds in selecting their LDOs.