7.1 Overview

The LM5141-Q1 is a switching controller that features all of the functions necessary to implement a high-efficiency buck power supply that can operate over a wide input-voltage range. The LM5141-Q1 is configured to provide a single fixed 3.3-V or 5-V output, or an adjustable output between 1.5 V to 15 V. This easy-to-use controller integrates high-side and low-side MOSFET drivers capable of sourcing 3.25 A and sinking 4.25 A peak. The control method is current mode control, which provides inherent line feed-forward, cycle-by-cycle current limiting, and ease-of-loop compensation. With the OSC pin connected to VDD, the default oscillator frequency is 2.2 MHz. With the OSC pin grounded, the oscillator frequency is 440 kHz. The LM5141-Q1 can be synchronized by applying an external clock to the DEMB pin. Fault protection features include current limiting, thermal shutdown, and remote shutdown capability.

The LM5141-Q1 incorporates features that simplify compliance with the CISPR and automotive EMI requirements. The LM5141-Q1 has optional spread spectrum to reduce the peak EMI and gate drivers with slew-rate control. The QFN-24 package features an exposed pad to aid in thermal dissipation.