SNVU697 September   2020 LMQ62440-Q1

 

  1.   Trademarks
  2. 1Introduction
    1. 1.1 LMQ62440-Q1 Synchronous Step-Down Voltage Converter
  3. 2Quick Start
  4. 3Detailed Descriptions
  5. 4EVM Performance
    1. 4.1 Board Efficiency, Load Regulation, Transient, and Steady-state Curves
    2. 4.2 EMI Test Results
    3. 4.3 Thermal Picture
  6. 5EVM Schematic Entry
  7. 6Bill of Materials
  8. 7Board Layout

LMQ62440-Q1 Synchronous Step-Down Voltage Converter

The LMQ62440-Q1 device is capable of driving up to 4 A of load current from a supply voltage ranging from 3 V to 36 V. The LMQ62440-Q1 is a peak current mode controlled device. The following are additional features that provide both flexible and easy-to-use solutions for a wide range of applications:

  • Integrated VIN bypass capacitors to achieve exceptional EMI performance, even in optimization-constrained layouts
  • Factory programmed 2.1-MHz switching frequency
  • Synchronization to an external clock
  • Pin-selectable forced pulse width modulation mode (FPWM) for constant frequency operation
  • Pin-selectable auto mode for improved light load efficiency
  • Pin-selectable spread spectrum enable/disable
  • Power-good flag
  • Precision enable for programmable undervoltage lockout
  • Automatic frequency foldback at light load and optional external bias to improve efficiency over the entire load range
  • Package optimized for low noise and easy thermal management

Protection features include the following:

  • Thermal shutdown
  • Input undervoltage lockout
  • Cycle-by-cycle current limiting
  • Hiccup short-circuit protection

The pin configuration of the LMQ62440-Q1 is shown in Figure 1-1 and the application circuit is shown in Figure 1-2. Refer to the LMQ62440-Q1 Automotive 3-V to 36-V, 4-a, Low-Noise Synchronous Step-Down Converter Data Sheet for more detailed feature descriptions and design guide.

GUID-24373596-1BF3-4F95-B541-55D77947250F-low.gifFigure 1-1 LMQ62440-Q1 Pin Configuration (14-Pin WQFN-HR Package Top View)
GUID-5AF7BFD7-D661-497B-B05C-B96E53EF1757-low.gifFigure 1-2 LMQ62440-Q1 Application Circuit