Texas Instruments LM25117 Synchronous Buck Controller is intended for step-down regulator applications from a high voltage or widely varying input supply. The control method is based upon current mode control utilizing an emulated current ramp. TI LM25117 Synchronous Buck Controller drives external high-side and low-side NMOS power switches with adaptive dead-time control. A user-selectable diode emulation mode enables discontinuous mode operation for improved efficiency at light load conditions. Efficiency is further improved by a high voltage bias regulator that allows external bias supply. LM25117 provides a unique analog telemetry feature that offers average output current information. Additional features include thermal shutdown, frequency synchronization, hiccup mode current limit, and adjustable line under-voltage lockout.