Wide VIN DC/DC controller targets 48V automotive systems

March 21, 2016 // By PAUL BUCKLEY
TI's LM5140-Q1 controller
Texas Instruments has introduced a 2.2-MHz, dual-channel synchronous buck converter with a set of features designed to reduce 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 that speeds manufacturing. Together with TI’s WEBENCH Automotive Design tool, the LM5140-Q1 enables engineers to get their automotive designs to market faster.

The controller has a wide 3.8-V to 65-V operating range to handle start-stop and load-dump conditions for 12-V/24-V lead-acid and emerging 48-V Lithium-ion automotive batteries.

The device's 2.2-MHz operation with external synchronization capability moves switching noise above the sensitive AM band and eliminates the need for frequency hopping.

The LM5140-Q1's 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.

The controller's low 35-uA quiescent current (IQ) in standby (one channel operating with no load) extends battery life in 'always on' applications.

The device's wettable flank packaging enables post-solder visual inspection to speed manufacturing.

The LM5140-Q1 joins the recently released LM53600-Q1, LM53601-Q1, LM53602-Q1 and LM53603-Q1 buck converters to create a complete family of controllers and converters designed for automotive systems that draw from less than 1 A of power to more than 10 A. All of these devices feature greater than 2-MHz switching frequency, low operating IQ and EMI reduction features.