The LM3676 step-down DC-DC converter is optimized for powering low voltage circuits from a single Li-Ion cell battery and input voltage rails from 2.9V to 5.5V. It provides up to 600mA load current, over the entire input voltage range. There are several different fixed voltage output options available as well as an adjustable output voltage version. The LM3676 has a mode-control pin that allows the user to select continuous Pulse Width Modulation (PWM) mode over the complete load range or an intelligent PFM-PWM mode that changes modes depending on the load. PWM mode offers superior efficiency under high load conditions (>100mA) and the lowest output noise performance. In Auto mode, PFM-PWM, hysteretic PFM extends the battery life through reduction of the quiescent current to 16µA (typ.) during light loads and system standby. The LM3676 is available in a 8-lead non-pullback WSON package in leaded (PB) and lead-free (NO PB) versions. A high switching frequency of 2 MHz (typ) allows use of tiny surface-mount components, an inductor and two ceramic capacitors.