LM3280TLX-290/NOPB is a type of multi-functional Power Management Unit incorporating three low-dropout LDO voltage regulators and one step-down PWM DC-DC converter with an internal Bypass FET. With an analog input (VCON), the step-down converter's output voltage can be set as a way of optimizing the efficiency of the RF PA at various power levels. The LDO operates with a nominal output voltage of 2.85V and a maximum load current capability of 20mA for a reference voltage required by linear RF power amplifiers. It is specifically designed for low-power handheld applications such as cellular phones, hand-held radios, and more.