SNVU879 June   2024 LMR36503E-Q1

 

  1.   1
  2.   Description
  3.   Get Started
  4.   Features
  5.   Applications
  6.   6
  7. 1Evaluation Module Overview
    1. 1.1 Introduction
    2. 1.2 Kit Contents
    3. 1.3 Specification
    4. 1.4 Device Information
  8. 2Hardware
    1. 2.1 EVM Setup
      1. 2.1.1 Quick Start
      2. 2.1.2 Test Points
      3. 2.1.3 Jumpers
  9. 3Implementation Results
    1. 3.1 Performance Data and Results
      1. 3.1.1 Efficiency, Load Regulation, and Dropout
      2. 3.1.2 Load Transients
      3. 3.1.3 Steady State
      4. 3.1.4 Line Transient
    2. 3.2 Thermal Images
  10. 4Hardware Design Files
    1. 4.1 Schematic
    2. 4.2 Board Layout
    3. 4.3 Bill of Materials
  11. 5Additional Information
    1. 5.1 Trademarks

2.1 EVM Setup

This section describes the test points and connectors on the EVM and how to properly connect, set up, and use the LMR36503MSCEEVM.

By default, the EVM utilizes a MODE/SYNC trim part. The MODE/RT jumper J4 is connected between pins 1 and 2. By default, this means that the part is operating in a 2.2MHz fixed frequency, PFM light-load operating mode. To access FPWM light-load operating mode, depopulate resistor R5 and connect pins 2 and 3 of J4.

LMR36503MSCEEVM EVM Board Connections Figure 2-1 EVM Board Connections

The test setup consists of the following instruments in addition to the EVM board.

  • Power Supply: The input DC voltage source must be capable of at least 65V and 2A.
  • Load: The load must be an electronic, constant-current (CC) or constant-resistance (CR) mode load, capable of supporting up to 300mA up to 5V. For no-load input current measurements, the electronic load must be disconnected.
  • Multimeters:
    • Voltmeter 1: Measures input voltage at VIN (TP1) and GND (TP7)
    • Voltmeter 2: Measures output voltage at VOUT (TP2) and GND (TP4)
    • Ammeter 1: Measures input current.
    • Ammeter 2: Measures output current.
  • Oscilloscope: With the scope set to 20MHz bandwidth, and AC coupling, measure the output voltage ripple directly across an output capacitor with a short ground lead. The oscilloscope probe tip must be placed on the positive terminal of the output capacitor, and the ground lead must be placed on the negative terminal of the output capacitor. TI does not recommend using a long-leaded ground connection because the connection can induce additional noise due to a large ground loop. To measure other waveforms, adjust the oscilloscope as necessary.