SNVA103B October   2005  – February 2022 LM2743

 

  1.   Trademarks
  2. 1Introduction
  3. 2Additional Footprints
  4. 3Guidelines for Additional Options
  5. 4Typical Application Circuit
  6. 5Performance Characteristics
    1. 5.1 Load Transient Response
    2. 5.2 Switch Node Voltage and Output Ripple Voltage
  7. 6PCB Layout Diagrams
  8. 7Revision History

1 Introduction

This user's guide describes the LM2743 printed circuit board (PCB) design and provides an example typical application circuit. The demo board allows component design flexibility in order to demonstrate the versatility of the LM2744 IC.

The demo board contains a voltage-mode, high-speed synchronous buck regulator controller with an external adjustable reference voltage between 0.5 V and 1.5 V. The demo board design incorporates the LM4140 high precision low noise reference IC providing 1.0 V to the reference pin (VREF). Though the control sections of the IC are rated for 3 to 6 V (VCC), the driver sections are designed to accept input supply rails (VIN) as high as 14 V. It operates at a fixed frequency, adjustable from 50 kHz to 1 MHz with one external resistor.

The demo board design regulates to an output voltage of 1.2 V at 3.5 A with a switching frequency of 1 MHz. Note, the demo board is optimized for a 1-MHz, 14-V input voltage compensation design. If another switching frequency and input voltage is desired, please consult the LM2744 Low Voltage N-Chan MOSFET Synch Buck Regr Cntrl w/ Ext Ref data sheet for control loop compensation procedures. For additional design modifications, refer to the Design Consideration section of the LM2744 Low Voltage N-Chan MOSFET Synch Buck Regr Cntrl w/ Ext Ref data sheet.