The LM5145-Q1 is a 75-V synchronous buck controller with all of the functions necessary to implement a high-efficiency step-down power supply. The output voltage range is from 0.8 V to 60 V. The voltage-mode control architecture uses input feedforward for excellent line transient response over a wide V_IN range. Voltage-mode control supports the wide duty cycle range for high input voltage and low dropout applications as well as when a high-voltage conversion ratio (for example, 10-to-1) is required. Current sensing for cycle-by-cycle current limit can be implemented with either the low-side FET R_DS(on) or a current sense resistor. The operating frequency is programmable from 100 kHz to 1 MHz. The LM5145-Q1 drives external high-side and low-side NMOS power switches with robust 7.5-V gate drivers suitable for standard threshold MOSFETs. Adaptive dead-time control between the high-side and low-side drivers minimizes body diode conduction during switching transitions. An external bias supply can be connected to the VCC pin to improve efficiency in high-voltage applications. A user-selectable diode emulation feature enables DCM operation for improved efficiency and lower dissipation at light-load conditions.