The LM3243 is a DC-DC converter optimized for powering multi-mode 2G/3G/4G RF power amplifiers (PAs) from a single Lithium-Ion cell. The LM3243 steps down an input voltage from 2.7V to 5.5V to a dynamically adjustable output voltage of 0.4V to 3.6V. The output voltage is set through a VCON analog input that adjusts the output voltage to ensure efficient operation at all power levels of the RF PA.
The LM3243 operates in constant frequency PWM mode producing a small and predictable amount of output voltage ripple. This enables best ECTEL power requirements in GMSK and EDGE spectral compliance, with the minimal amount of filtering and excess headroom. When operating in PFM mode, the LM3243 enables the lowest DG09 current consumption and therefore maximizes system efficiency.