LM25017

LM25017 SNVS951F – DECEMBER 2012 – REVISED MAY 2021 LM25017 48-V, 650-mA Constant On-Time Synchronous Buck/Fly-Buck™ Regulator 1 Features Wide 7.5-V to 48-V input range Integrated 650-mA high-side and low-side switches No schottky diode required Constant on-time control No loop compensation required Ultra-fast transient response Nearly constant operating frequency Intelligent peak current limit Adjustable output voltage from 1.225 V Precision 2% feedback reference Frequency adjustable to 1 MHz Adjustable undervoltage lockout (UVLO) Remote shutdown Thermal shutdown Create a custom design using the LM25017 with the WEBENCH® power designer 2 Applications Industrial equipment Smart power meters Telecommunication systems Isolated bias supply (Fly-Buck™) 3 Description The LM25017 device is a 48-V, 650-mA synchronous step-down regulator with integrated high-side and low-side MOSFETs. The constant on-time (COT) control scheme employed in the LM25017 device requires no loop compensation, provides excellent transient response, and enables very high step-down ratios. The on-time varies inversely with the input voltage resulting in nearly constant frequency over the input voltage range. A high voltage startup regulator provides bias power for internal operation of the IC and for integrated gate drivers. A peak current limit circuit protects against overload conditions. The undervoltage lockout (UVLO) circuit allows the input undervoltage threshol...