Wide Vin Dual 2.2MHz low Iq Synchronous Buck Controller

The LM5140-Q1 is a dual synchronous buck controller intended for high voltage wide VIN step-down converter applications. The control method is based on current mode control. Current mode control provides inherent line feedforward, cycle-by-cycle current limiting, and easier loop compensation.

The LM5140-Q1 features adjustable slew rate control to simplify compliance with the CISPR and automotive EMI requirements. The LM5140-Q1 operates at selectable switching frequencies of 2.2 MHz or 440 kHz with the two controller channels switching 180°; out of phase. In light or no-load conditions, the LM5140-Q1 operates in skip cycle mode for improved low power efficiency. The LM5140-Q1 includes a high voltage bias regulator with automatic switchover to an external bias supply to improve efficiency and reduce input current. Additional features include frequency synchronization, cycle-by-cycle current limit, hiccup mode fault protection for sustained overloads, independent power good outputs, and independent enable inputs.