The OT1153 series on-chip regulators allow for efficient on-chip conversion of IO voltages to Core voltages. E.g. 3.3V to 1.2V with only one external inductor and one external capacitor. 2MHz conversion frequency is used to minimize the size of the external components. Input voltages of 2.5-5V are available and currents up to 80mA. Versions with internal or external references are available. In normal operation constant on time PWM modulation is used, with an optional low power mode in which where the synchronous rectifier is disabled.