The Si9166 is a programmable topology controller for today's continuous changing portable electronic market. Si9166 provides flexibility of utilizing various battery configurations and chemistries such as NiCd, NiMhy, or Li+ with input voltage range of 2.7 V to 6 V. An additional flexibility is provided with topology programmability to power multiple loads such as power amplifiers, microcontrollers, or baseband logic IC's. The converters can be programmed to be synchronous Buck or Boost topology. For ultra-high efficiency, converters are designed to operate in synchronous rectified PWM mode under full load while transforming into externally