The LM644x0-Q1 derives from a family of automotive, synchronous, buck, DC/DC converters with excellent efficiency and ultra-low IQ. With integrated high-side and low-side MOSFETs, up to 6A of output current is delivered over a wide input voltage range from 3V to 36V, with support for load-dump transients up to 42V. The converter implements soft recovery from dropout to eliminate overshoot on the output.

The LM644x0-Q1 incorporates numerous features for excellent EMI performance, including spread-spectrum frequency modulation, a low-EMI Enhanced HotRod QFN package that mitigates switch-node ringing, and a symmetrical pinout for excellent input capacitor placement. The switching frequency is synchronizable between 200kHz and 2.2MHz to avoid sensitive frequency bands, while optimizing efficiency or design size based on the specific requirements of the application.

PFM mode enables frequency foldback during light-load operation, allowing an unloaded current consumption of only 7µA (typical) and high light-load efficiency. A seamless transition between PWM and PFM modes, along with low MOSFET on-resistances and an external bias input, provides exceptional efficiency and thermal performance across the entire load range. The package has several NC pins between critical power pins, which improve the Failure Modes and Effects Analysis (FMEA) result.Read more