Wide Vin Automotive DC-DC Controller

Texas Instruments (TI) today introduced a 2.2-MHz, dual-channel synchronous buck converter with a unique set of features designed to significantly reduce electromagnetic interference (EMI) and high-frequency noise in high-voltage dc-dc step-down applications such as automotive infotainment and high-end cluster power-supply systems. The LM5140-Q1 controller includes dual outputs with phase interleaving and is offered in wettable flank packaging (40-pin VQFN and 10-pin WSON are available in addition to the non-wettable 16-pin HTSSOP) that speeds manufacturing.

The LM5140-Q1 uses external MOSFETs to support up to 10-A dual-channel loads for high-end infotainment systems and other noise-sensitive systems. There will be a demonstration of the LM5140-Q1 buck converter in TI's booth (No. 1617) at this week’s Applied Power Electronics Conference (APEC).

LM5140-Q1 key features and benefits: Wide 3.8-V to 65-V operating range handles start-stop and load-dump conditions for 12-V/24-V lead-acid and emerging 48-V Lithium-ion automotive batteries. Read the application note, "Maintain output voltage regulation during automotive cold-crank conditions." 2.2-MHz operation with external synchronization capability moves switching noise above the sensitive AM band, eliminating the need for frequency hopping.

The LM5140-Q1 also features: Unique, adjustable gate-drive slew-rate control reduces EMI emissions by up to 10 dB with less than a 1 percent reduction in efficiency, which reduces external EMI filtering, saves printed circuit board (PCB) area, and simplifies compliance with CISPR 25 automotive EMI requirements. Watch the video and read the blog post on how to use slew-rate control for EMI reduction. Low 35-uA quiescent current (I(Q)) in standby (one channel operating with no load) extends battery life in "always on" applications. Wettable flank packaging enables post-solder visual inspection to speed manufacturing. Read the blog, "The value of wettable flank-plated QFN packaging for automotive applications."