Home Power management AC/DC & DC/DC converters (integrated FET)
Home
Power management
AC/DC & DC/DC converters (integrated FET)
NEW

LM68645-Q1

PREVIEW

Automotive 3-V to 65-V, 4.5A synchronous step-down converter optimized for power density and low EMI

Order now
Data sheet

LM68645-Q1

PREVIEW
Data sheet Order now

Product details

Rating Automotive Operating temperature range (°C) -40 to 150 TI functional safety category Functional Safety-Compliant Topology Buck Type Converter Iout (max) (A) 4.5 Vin (min) (V) 3 Vin (max) (V) 65 Switching frequency (min) (kHz) 360 Switching frequency (max) (kHz) 2420 Features Adjustable switching frequency, Enable, Frequency synchronization, Low Noise, Overcurrent protection, Power good, Spread Spectrum, Thermal shutdown Vout (min) (V) 0.8 Vout (max) (V) 40 Duty cycle (max) (%) 98
Rating Automotive Operating temperature range (°C) -40 to 150 TI functional safety category Functional Safety-Compliant Topology Buck Type Converter Iout (max) (A) 4.5 Vin (min) (V) 3 Vin (max) (V) 65 Switching frequency (min) (kHz) 360 Switching frequency (max) (kHz) 2420 Features Adjustable switching frequency, Enable, Frequency synchronization, Low Noise, Overcurrent protection, Power good, Spread Spectrum, Thermal shutdown Vout (min) (V) 0.8 Vout (max) (V) 40 Duty cycle (max) (%) 98
WQFN-FCRLF (RZT) 20 9.36 mm² 2.6 x 3.6
  • AEC-Q100 qualified for automotive applications:
    • Temperature grade 1: –40°C to +125°C, TA
  • Functional Safety-Compliant
    • Developed for functional safety applications
    • Documentation to aid with ISO26262 compliant designs planned
    • Systematic capability up to ASIL-D
    • Hardware capability up to ASIL-C
    • Analog built-in-self-test at start-up
    • Redundant and fast (0.35µs) VOUT monitor
    • Feedback path failure detection
    • Redundant temperature sensor
    • Excellent pin FMEA and pin spacing
  • Wide input voltage range: 3V to 70V
  • Designed for low EMI requirements
    • Facilitates CISPR 25 class 5 compliance
    • ±5% dual-random spread spectrum
    • Enhanced HotRod™ QFN package with symmetrical pinout
    • Switching frequency from 300kHz to 2.2MHz
    • Pin-configurable 400kHz and 2.2MHz
    • Pin-configurable AUTO or FPWM operation
  • Low minimum on time: 40ns (maximum)
    • Enables 36V to 3.3V conversion at 2.2MHz
  • High-efficiency power conversion at all loads
    • > 94% peak efficiency at 24VIN, 5VOUT, 400kHz
    • 2.5µA PFM no-load input current
  • High power density
    • Internal compensation, current limit, and TSD
    • 3.6mm × 2.6mm, wettable flank, 20-pin package
    • Pin compatible with LM656x5-Q1
    • ϴJA = 25.5°C/W (LM65645-Q1EVM)
  • Create a custom design using the with the WEBENCH Power Designer
  • AEC-Q100 qualified for automotive applications:
    • Temperature grade 1: –40°C to +125°C, TA
  • Functional Safety-Compliant
    • Developed for functional safety applications
    • Documentation to aid with ISO26262 compliant designs planned
    • Systematic capability up to ASIL-D
    • Hardware capability up to ASIL-C
    • Analog built-in-self-test at start-up
    • Redundant and fast (0.35µs) VOUT monitor
    • Feedback path failure detection
    • Redundant temperature sensor
    • Excellent pin FMEA and pin spacing
  • Wide input voltage range: 3V to 70V
  • Designed for low EMI requirements
    • Facilitates CISPR 25 class 5 compliance
    • ±5% dual-random spread spectrum
    • Enhanced HotRod™ QFN package with symmetrical pinout
    • Switching frequency from 300kHz to 2.2MHz
    • Pin-configurable 400kHz and 2.2MHz
    • Pin-configurable AUTO or FPWM operation
  • Low minimum on time: 40ns (maximum)
    • Enables 36V to 3.3V conversion at 2.2MHz
  • High-efficiency power conversion at all loads
    • > 94% peak efficiency at 24VIN, 5VOUT, 400kHz
    • 2.5µA PFM no-load input current
  • High power density
    • Internal compensation, current limit, and TSD
    • 3.6mm × 2.6mm, wettable flank, 20-pin package
    • Pin compatible with LM656x5-Q1
    • ϴJA = 25.5°C/W (LM65645-Q1EVM)
  • Create a custom design using the with the WEBENCH Power Designer

The LM686x5-Q1 are a family of automotive buck converters designed for high efficiency, high power density, and ultra-low electromagnetic interference (EMI). The converters operate over a wide input voltage range of 3V to 70V (75V tolerant) reducing the need for external input surge protection. The LM686x5-Q1 comes with pin selectable fixed output voltages of 3.3V and 5V or in adjustable configuration. The low EMI operation is enabled with minimized loop inductance and optimized switch node slew rate. The current-mode control architecture with a 30ns typical minimum on-time allows high conversion ratios at high frequencies coupled with a fast transient response and excellent load and line regulation.

The LM686x5-Q1 buck converters are specifically intended for functional safety relevant applications. An array of safety features including ABIST at start-up, redundant and fast VOUT monitoring, feedback path failure detection, redundant temperature sensor, thermal shutdown, and current limiting significantly reduce the residual failure-in-time (FIT).

The LM686x5-Q1 are a family of automotive buck converters designed for high efficiency, high power density, and ultra-low electromagnetic interference (EMI). The converters operate over a wide input voltage range of 3V to 70V (75V tolerant) reducing the need for external input surge protection. The LM686x5-Q1 comes with pin selectable fixed output voltages of 3.3V and 5V or in adjustable configuration. The low EMI operation is enabled with minimized loop inductance and optimized switch node slew rate. The current-mode control architecture with a 30ns typical minimum on-time allows high conversion ratios at high frequencies coupled with a fast transient response and excellent load and line regulation.

The LM686x5-Q1 buck converters are specifically intended for functional safety relevant applications. An array of safety features including ABIST at start-up, redundant and fast VOUT monitoring, feedback path failure detection, redundant temperature sensor, thermal shutdown, and current limiting significantly reduce the residual failure-in-time (FIT).
filter Find other AC/DC & DC/DC converters (integrated FET)
Download View video with transcript Video

Technical documentation

star =Top documentation for this product selected by TI
No results found. Please clear your search and try again.
View all 3
Type Title Date
* Data sheet LM686x5-Q1 High Performance, Functional Safety Power Converter, 3V to 70V , Pin-Compatible, 2.5A/3.5A/4.5A, Automotive , Low EMI, Synchronous Buck Converter datasheet PDF | HTML 21 Oct 2024
EVM User's guide LM68645-Q1 Evaluation Module User's Guide PDF | HTML 21 Oct 2024
Certificate LM68645EVM EU Declaration of Conformity (DoC) 04 Oct 2024

Design & development

For additional terms or required resources, click any title below to view the detail page where available.

Evaluation board

LM68645EVM — LM68645-Q1 evaluation module

The LM68645-Q1 evaluation module (EVM) helps designers evaluate the operation and performance of the LM68645 family of wide input voltage buck converters. The LM68645EVM is configured to deliver a 5V output to a load requiring 4.5A or less. The LM68645EVM can be used in many different (...)

User guide: PDF | HTML
Not available on TI.com
Driver or library

LM68645-Q1-FS — Functional safety documentation and full datasheet for LM68645-Q1

LM68645-Q1 functional safety documentation and full datasheet
Supported products & hardware

Supported products & hardware

Products
AC/DC & DC/DC converters (integrated FET)
LM68645-Q1 — Automotive 3-V to 65-V, 4.5A synchronous step-down converter optimized for power density and low EMI
Request
Package Pins CAD symbols, footprints & 3D models
WQFN-FCRLF (RZT) 20 Ultra Librarian
TI's Standard Terms and Conditions for Evaluation Items apply.

Ordering & quality

Information included:
  • RoHS
  • REACH
  • Device marking
  • Lead finish/Ball material
  • MSL rating/Peak reflow
  • MTBF/FIT estimates
  • Material content
  • Qualification summary
  • Ongoing reliability monitoring
Information included:
  • Fab location
  • Assembly location

Support & training

TI E2E™ forums with technical support from TI engineers

View all forum topics

Content is provided "as is" by TI and community contributors and does not constitute TI specifications. See terms of use.

If you have questions about quality, packaging or ordering TI products, see TI support. ​​​​​​​​​​​​​​

Videos