2.2-MHz, low-quiescent-current buck converter significantly reduces system noise and saves space in sensitive automotive power-supply systems
Texas Instruments 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 that speeds manufacturing. Together with TI’s WEBENCH® Automotive Design tool, the LM5140-Q1 enables engineers to get their automotive designs to market faster.
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.
- 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 (IQ) 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.”
For industrial applications requiring a regulated voltage above 15 V such as programmable logic controllers or factory automation equipment, read the blog post, “How to extend a controller’s output-voltage range.”
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.
| Part number | Operating voltage range (abs max) | Operating frequency | IQ (operating/ shutdown) | Package |
| LM5140-Q1 | 3.8 V-65 V (70 V) | 2.2 MHz or 440 kHz | 35 uA/9 uA | 40-pin VQFN* |
| LM53600-Q1 | 3.5 V-36 V (42 V) | 2.1 MHz | 23 uA/1.8 uA | 10-pin WSON* |
| LM53601-Q1 | 3.5 V-36 V (42 V) | 2.1 MHz | 23 uA/1.8 uA | 10-pin WSON* |
| LM53602-Q1 | 3.5 V-36 V (42 V) | 2.1 MHz | 24 uA/1.7 uA | 16-pin HTSSOP |
| LM53603-Q1 | 3.5 V-36 V (42 V) | 2.1 MHz | 24 uA/1.7 uA | 16-pin HTSSOP |
* Wettable flank packaging.
The LM5140-Q1 uses external metal-oxide semiconductor field-effect transistors (MOSFETs) to support up to 10-A dual-channel loads for high-end infotainment systems and other noise-sensitive systems. The LM53600-Q1 and LM53601-Q1 support 650-mA and 1-A load current, respectively, for emerging advanced driver assistance (ADAS) systems. The LM53602-Q1 and LM53603-Q1 deliver 2-A and 3-A loads, respectively, for higher-current ADAS and infotainment systems.
Design an automotive camera module
Download the “Automotive camera module reference design for uncompressed digital video with wide VIN front end” to view a full automotive camera module reference design for uncompressed digital video. The reference design includes the LM53601-Q1 converter and DS90UB913A 12-bit serializer. The reference design meets all industry tests including ISO7637 pulse, reverse battery, input over-voltage and CISPR25 Class 5-conducted EMI.
Create a 30-W surround-view ADAS system
Download the “System Level reference design for 30-W ADAS system with required automotive protections” to view a complete ADAS system reference design featuring TI’s LM53603-Q1 converter, LM26420-Q1 regulator and LM3880 sequencer. The reference design meets all industry tests including ISO7637 pulse, reverse battery, input over-voltage and CISPR25 Class 3-conducted EMI.
Availability, packaging and pricing
Available in volume now from TI and its authorized distributors, the LM5140-Q1 is packaged in an 8-pin, 6-mm by 6-mm by 0.9-mm very thin quad flat no-lead (VQFN) package and priced atUS$3.90 in 1,000-unit quantities. Order the LM5140-Q1 evaluation module and download the LM5140-Q1 quick-start DC/DC synchronous buck converter design tool.
For more information, samples and an evaluation module, seewww.ti.com/lm5140q1-pr.
