LM25117PMHE/NOPB

DC/DC контроллер, токовый режим, 4.5В до 42В, 1 выход, синхронный понижающий, 750кГц, HTSSOP-20.

The LM25117PMHE/NOPB is a current-mode Synchronous Buck Controller with tracking. It 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. current-mode control provides inherent line feed-forward, cycle-by-cycle current limiting and ease of loop compensation. The use of an emulated control ramp reduces noise sensitivity of the pulse-width modulation circuit, allowing reliable control of very small duty cycles necessary in high input voltage applications. The operating frequency is programmable from 50 to 750kHz. The LM25117 drives external high-side and low-side NMOS power switches with adaptive dead-time control. User-selectable diode emulation mode enables discontinuous mode operation for improved efficiency at light load conditions. A high voltage bias regulator that allows external bias supply further improves efficiency.