The LM3668SD-2833/NOPB is a high-efficiency dual-mode single inductor buck-boost DC-to-DC Converter optimized for powering low voltage circuits from a Li-ion battery and input voltage rails between 2.5 and 5.5V. It has the capability to support up to 1A output current over the output voltage range. The LM3668 regulates the output voltage over the complete input voltage range by automatically switching between buck or boost modes depending on the input voltage. The LM3668 has 2 N-channel MOSFETS and 2 P-channel MOSFETS arranged in a topology that provides continuous operation through the buck and boost operating modes. There is a MODE pin that allows the user to choose between an intelligent automatic PFM-PWM mode operation and forced PWM operation. During PWM mode, a fixed-frequency 2.2MHz (typical) is used. PWM mode drives load up to 1A. Hysteretic PFM mode extends the battery life through reduction of the quiescent current to 45µA (typical) at light loads during system standby.
Internal synchronous rectification provides high efficiency
Current overload and thermal shutdown protection
Internal soft-start - 600µs maximum startup time after VIN settled
