Switched mode power supply design for low level logic circuits

Low voltage logic levels (3.3 V) are becoming a fact of life and even lower-voltage devices (1.0 V) are on the horizon. Thus, design, manufacture and selection of power supplies need to overcome severe tolerance problems. While 5 V semiconductor devices have developed a high tolerance to power supplies, low-voltage chips have not. The 1.0 V circuits now under development, for example, will require their power source to maintain an overall worst-case deviation of less than 20 mV. This deviation includes absolute value, static and dynamic regulation, noise, ripple and transient response. Power efficiency demands switched mode regulation with remote sensing causing instability dangers when a wide band filter is operating within the sensing loop.