overview

1. General Description

<p class="bady">The Evaluation Board demonstrates the RT4527A to be designed for high efficiency driver for white LEDs. It is suitable for single/two cell battery input to drive LED light bars which contains six strings in parallel and up to 10 WLEDs per string.</p> <p class="bady">The RT4527A contains I²C interface for controlling the dimming mode, operating frequency and the LED current. The internal 250mΩ, 36V power switch with current-mode control provides overcurrent protection. The switching frequency of the RT4527A is also adjustable from 100kHz to 1.6MHz, which allows flexibility between efficiency and component size.</p> <p class="bady">The RT4527A is available in the WQFN-20L 3.5x3.5 package.</p>

2. Performance Sepcification Summary

<p class="bady">Summary of the RT4527AGQW Evaluation Board performance specificiaiton is provided in Table 1. The ambient temperature is 25°C.</p> <p class="MsoNormal">Table 1. RT4527A Evaluation Board Performance Specification Summary</p> <div> <table class="MsoTableLightListAccent2" border="1" cellspacing="0" cellpadding="0" width="681" style="border-collapse:collapse;border:none"> <tr style="height:17.0pt"> <td width="209" style="width:156.8pt;border:solid #009EB8 1.0pt;background: #009EB8;padding:0cm 5.4pt 0cm 5.4pt;height:17.0pt"> <p class="ListParagraph1CxSpFirst">Specification</p> </td> <td width="283" style="width:212.05pt;border:solid #009EB8 1.0pt;border-left: none;background:#009EB8;padding:0cm 5.4pt 0cm 5.4pt;height:17.0pt"> <p class="ListParagraph1CxSpMiddle">Test Conditions</p> </td> <td width="44" style="width:32.9pt;border:solid #009EB8 1.0pt;border-left:none; background:#009EB8;padding:0cm 5.4pt 0cm 5.4pt;height:17.0pt"> <p class="ListParagraph1CxSpMiddle">Min</p> </td> <td width="49" style="width:37.1pt;border:solid #009EB8 1.0pt;border-left:none; background:#009EB8;padding:0cm 5.4pt 0cm 5.4pt;height:17.0pt"> <p class="ListParagraph1CxSpMiddle">Typ</p> </td> <td width="47" style="width:35.0pt;border:solid #009EB8 1.0pt;border-left:none; background:#009EB8;padding:0cm 5.4pt 0cm 5.4pt;height:17.0pt"> <p class="ListParagraph1CxSpMiddle">Max</p> </td> <td width="49" style="width:36.6pt;border:solid #009EB8 1.0pt;border-left:none; background:#009EB8;padding:0cm 5.4pt 0cm 5.4pt;height:17.0pt"> <p class="ListParagraph1CxSpLast">Unit</p> </td> </tr> <tr style="height:17.0pt"> <td width="209" style="width:156.8pt;border:solid #009EB8 1.0pt;border-top: none;padding:0cm 5.4pt 0cm 5.4pt;height:17.0pt"> <p class="ListParagraph1CxSpFirst">Input Voltage Range</p> </td> <td width="283" style="width:212.05pt;border-top:none;border-left:none; border-bottom:solid #009EB8 1.0pt;border-right:solid #009EB8 1.0pt; padding:0cm 5.4pt 0cm 5.4pt;height:17.0pt"> </td> <td width="44" style="width:32.9pt;border-top:none;border-left:none;border-bottom: solid #009EB8 1.0pt;border-right:solid #009EB8 1.0pt;padding:0cm 5.4pt 0cm 5.4pt; height:17.0pt"> <p class="ListParagraph1CxSpMiddle">2.7</p> </td> <td width="49" style="width:37.1pt;border-top:none;border-left:none;border-bottom: solid #009EB8 1.0pt;border-right:solid #009EB8 1.0pt;padding:0cm 5.4pt 0cm 5.4pt; height:17.0pt"> <p class="ListParagraph1CxSpMiddle">--</p> </td> <td width="47" style="width:35.0pt;border-top:none;border-left:none;border-bottom: solid #009EB8 1.0pt;border-right:solid #009EB8 1.0pt;padding:0cm 5.4pt 0cm 5.4pt; height:17.0pt"> <p class="ListParagraph1CxSpMiddle">24</p> </td> <td width="49" style="width:36.6pt;border-top:none;border-left:none;border-bottom: solid #009EB8 1.0pt;border-right:solid #009EB8 1.0pt;padding:0cm 5.4pt 0cm 5.4pt; height:17.0pt"> <p class="ListParagraph1CxSpLast">V</p> </td> </tr> <tr style="height:1.0cm"> <td width="209" style="width:156.8pt;border:solid #009EB8 1.0pt;border-top: none;padding:0cm 5.4pt 0cm 5.4pt;height:1.0cm"> <p class="ListParagraph1CxSpFirst">Minimum CHx Regulation Voltage</p> </td> <td width="283" style="width:212.05pt;border-top:none;border-left:none; border-bottom:solid #009EB8 1.0pt;border-right:solid #009EB8 1.0pt; padding:0cm 5.4pt 0cm 5.4pt;height:1.0cm"> </td> <td width="44" style="width:32.9pt;border-top:none;border-left:none;border-bottom: solid #009EB8 1.0pt;border-right:solid #009EB8 1.0pt;padding:0cm 5.4pt 0cm 5.4pt; height:1.0cm"> <p class="ListParagraph1CxSpMiddle">0.4</p> </td> <td width="49" style="width:37.1pt;border-top:none;border-left:none;border-bottom: solid #009EB8 1.0pt;border-right:solid #009EB8 1.0pt;padding:0cm 5.4pt 0cm 5.4pt; height:1.0cm"> <p class="ListParagraph1CxSpMiddle">--</p> </td> <td width="47" style="width:35.0pt;border-top:none;border-left:none;border-bottom: solid #009EB8 1.0pt;border-right:solid #009EB8 1.0pt;padding:0cm 5.4pt 0cm 5.4pt; height:1.0cm"> <p class="ListParagraph1CxSpMiddle">0.56</p> </td> <td width="49" style="width:36.6pt;border-top:none;border-left:none;border-bottom: solid #009EB8 1.0pt;border-right:solid #009EB8 1.0pt;padding:0cm 5.4pt 0cm 5.4pt; height:1.0cm"> <p class="ListParagraph1CxSpLast">V</p> </td> </tr> <tr style="height:17.0pt"> <td width="209" style="width:156.8pt;border:solid #009EB8 1.0pt;border-top: none;padding:0cm 5.4pt 0cm 5.4pt;height:17.0pt"> <p class="ListParagraph1CxSpFirst">LED Channel Current</p> </td> <td width="283" style="width:212.05pt;border-top:none;border-left:none; border-bottom:solid #009EB8 1.0pt;border-right:solid #009EB8 1.0pt; padding:0cm 5.4pt 0cm 5.4pt;height:17.0pt"> </td> <td width="44" style="width:32.9pt;border-top:none;border-left:none;border-bottom: solid #009EB8 1.0pt;border-right:solid #009EB8 1.0pt;padding:0cm 5.4pt 0cm 5.4pt; height:17.0pt"> <p class="ListParagraph1CxSpMiddle">6</p> </td> <td width="49" style="width:37.1pt;border-top:none;border-left:none;border-bottom: solid #009EB8 1.0pt;border-right:solid #009EB8 1.0pt;padding:0cm 5.4pt 0cm 5.4pt; height:17.0pt"> <p class="ListParagraph1CxSpMiddle">--</p> </td> <td width="47" style="width:35.0pt;border-top:none;border-left:none;border-bottom: solid #009EB8 1.0pt;border-right:solid #009EB8 1.0pt;padding:0cm 5.4pt 0cm 5.4pt; height:17.0pt"> <p class="ListParagraph1CxSpMiddle">25</p> </td> <td width="49" style="width:36.6pt;border-top:none;border-left:none;border-bottom: solid #009EB8 1.0pt;border-right:solid #009EB8 1.0pt;padding:0cm 5.4pt 0cm 5.4pt; height:17.0pt"> <p class="ListParagraph1CxSpLast">mA</p> </td> </tr> <tr style="height:1.0cm"> <td width="209" style="width:156.8pt;border:solid #009EB8 1.0pt;border-top: none;padding:0cm 5.4pt 0cm 5.4pt;height:1.0cm"> <p class="ListParagraph1CxSpFirst">Output Voltage Limit</p> </td> <td width="283" style="width:212.05pt;border-top:none;border-left:none; border-bottom:solid #009EB8 1.0pt;border-right:solid #009EB8 1.0pt; padding:0cm 5.4pt 0cm 5.4pt;height:1.0cm"> <p class="ListParagraph1CxSpMiddle">Register address = ‘02h’, 5 bits step = 1V, </p> <p class="ListParagraph1CxSpMiddle">default = 36V, C_OUT = 4.7µF</p> </td> <td width="44" style="width:32.9pt;border-top:none;border-left:none;border-bottom: solid #009EB8 1.0pt;border-right:solid #009EB8 1.0pt;padding:0cm 5.4pt 0cm 5.4pt; height:1.0cm"> <p class="ListParagraph1CxSpMiddle">--</p> </td> <td width="49" style="width:37.1pt;border-top:none;border-left:none;border-bottom: solid #009EB8 1.0pt;border-right:solid #009EB8 1.0pt;padding:0cm 5.4pt 0cm 5.4pt; height:1.0cm"> <p class="ListParagraph1CxSpMiddle">36</p> </td> <td width="47" style="width:35.0pt;border-top:none;border-left:none;border-bottom: solid #009EB8 1.0pt;border-right:solid #009EB8 1.0pt;padding:0cm 5.4pt 0cm 5.4pt; height:1.0cm"> <p class="ListParagraph1CxSpMiddle">--</p> </td> <td width="49" style="width:36.6pt;border-top:none;border-left:none;border-bottom: solid #009EB8 1.0pt;border-right:solid #009EB8 1.0pt;padding:0cm 5.4pt 0cm 5.4pt; height:1.0cm"> <p class="ListParagraph1CxSpLast">V</p> </td> </tr> <tr style="height:17.0pt"> <td width="209" style="width:156.8pt;border:solid #009EB8 1.0pt;border-top: none;padding:0cm 5.4pt 0cm 5.4pt;height:17.0pt"> <p class="ListParagraph1CxSpFirst">Boost Operates at PWM Mode</p> </td> <td width="283" style="width:212.05pt;border-top:none;border-left:none; border-bottom:solid #009EB8 1.0pt;border-right:solid #009EB8 1.0pt; padding:0cm 5.4pt 0cm 5.4pt;height:17.0pt"> </td> <td width="44" style="width:32.9pt;border-top:none;border-left:none;border-bottom: solid #009EB8 1.0pt;border-right:solid #009EB8 1.0pt;padding:0cm 5.4pt 0cm 5.4pt; height:17.0pt"> <p class="ListParagraph1CxSpMiddle">0.1</p> </td> <td width="49" style="width:37.1pt;border-top:none;border-left:none;border-bottom: solid #009EB8 1.0pt;border-right:solid #009EB8 1.0pt;padding:0cm 5.4pt 0cm 5.4pt; height:17.0pt"> <p class="ListParagraph1CxSpMiddle">--</p> </td> <td width="47" style="width:35.0pt;border-top:none;border-left:none;border-bottom: solid #009EB8 1.0pt;border-right:solid #009EB8 1.0pt;padding:0cm 5.4pt 0cm 5.4pt; height:17.0pt"> <p class="ListParagraph1CxSpMiddle">1.6</p> </td> <td width="49" style="width:36.6pt;border-top:none;border-left:none;border-bottom: solid #009EB8 1.0pt;border-right:solid #009EB8 1.0pt;padding:0cm 5.4pt 0cm 5.4pt; height:17.0pt"> <p class="ListParagraph1CxSpLast">MHz</p> </td> </tr> <tr style="height:1.0cm"> <td width="209" style="width:156.8pt;border:solid #009EB8 1.0pt;border-top: none;padding:0cm 5.4pt 0cm 5.4pt;height:1.0cm"> <p class="ListParagraph1CxSpFirst">LED Current Accuracy</p> </td> <td width="283" style="width:212.05pt;border-top:none;border-left:none; border-bottom:solid #009EB8 1.0pt;border-right:solid #009EB8 1.0pt; padding:0cm 5.4pt 0cm 5.4pt;height:1.0cm"> <p class="ListParagraph1CxSpMiddle">PWM duty = 100%, I_CHx = 20mA,</p> <p class="ListParagraph1CxSpMiddle">PWM Freq = 1kHz</p> </td> <td width="44" style="width:32.9pt;border-top:none;border-left:none;border-bottom: solid #009EB8 1.0pt;border-right:solid #009EB8 1.0pt;padding:0cm 5.4pt 0cm 5.4pt; height:1.0cm"> <p class="ListParagraph1CxSpMiddle"><span lang="EN-US" style="font-size:10.0pt;font-family:Symbol">-</span>3</p> </td> <td width="49" style="width:37.1pt;border-top:none;border-left:none;border-bottom: solid #009EB8 1.0pt;border-right:solid #009EB8 1.0pt;padding:0cm 5.4pt 0cm 5.4pt; height:1.0cm"> <p class="ListParagraph1CxSpMiddle">--</p> </td> <td width="47" style="width:35.0pt;border-top:none;border-left:none;border-bottom: solid #009EB8 1.0pt;border-right:solid #009EB8 1.0pt;padding:0cm 5.4pt 0cm 5.4pt; height:1.0cm"> <p class="ListParagraph1CxSpMiddle">3</p> </td> <td width="49" style="width:36.6pt;border-top:none;border-left:none;border-bottom: solid #009EB8 1.0pt;border-right:solid #009EB8 1.0pt;padding:0cm 5.4pt 0cm 5.4pt; height:1.0cm"> <p class="ListParagraph1CxSpLast">%</p> </td> </tr> <tr style="height:1.0cm"> <td width="209" style="width:156.8pt;border:solid #009EB8 1.0pt;border-top: none;padding:0cm 5.4pt 0cm 5.4pt;height:1.0cm"> <p class="ListParagraph1CxSpFirst">LED Current Matching</p> </td> <td width="283" style="width:212.05pt;border-top:none;border-left:none; border-bottom:solid #009EB8 1.0pt;border-right:solid #009EB8 1.0pt; padding:0cm 5.4pt 0cm 5.4pt;height:1.0cm"> <p class="ListParagraph1CxSpMiddle">PWM duty = 100%, I_CHx = 20mA,</p> <p class="ListParagraph1CxSpMiddle">PWM Freq = 1kHz</p> </td> <td width="44" style="width:32.9pt;border-top:none;border-left:none;border-bottom: solid #009EB8 1.0pt;border-right:solid #009EB8 1.0pt;padding:0cm 5.4pt 0cm 5.4pt; height:1.0cm"> <p class="ListParagraph1CxSpMiddle"><span lang="EN-US" style="font-size:10.0pt;font-family:Symbol">-</span>2</p> </td> <td width="49" style="width:37.1pt;border-top:none;border-left:none;border-bottom: solid #009EB8 1.0pt;border-right:solid #009EB8 1.0pt;padding:0cm 5.4pt 0cm 5.4pt; height:1.0cm"> <p class="ListParagraph1CxSpMiddle">--</p> </td> <td width="47" style="width:35.0pt;border-top:none;border-left:none;border-bottom: solid #009EB8 1.0pt;border-right:solid #009EB8 1.0pt;padding:0cm 5.4pt 0cm 5.4pt; height:1.0cm"> <p class="ListParagraph1CxSpMiddle">2</p> </td> <td width="49" style="width:36.6pt;border-top:none;border-left:none;border-bottom: solid #009EB8 1.0pt;border-right:solid #009EB8 1.0pt;padding:0cm 5.4pt 0cm 5.4pt; height:1.0cm"> <p class="ListParagraph1CxSpLast">%</p> </td> </tr> <tr style="height:17.0pt"> <td width="209" rowspan="4" style="width:156.8pt;border:solid #009EB8 1.0pt; border-top:none;padding:0cm 5.4pt 0cm 5.4pt;height:17.0pt"> <p class="ListParagraph1CxSpFirst">DC Dimming Resolution</p> </td> <td width="283" style="width:212.05pt;border-top:none;border-left:none; border-bottom:solid #009EB8 1.0pt;border-right:solid #009EB8 1.0pt; padding:0cm 5.4pt 0cm 5.4pt;height:17.0pt"> <p class="ListParagraph1CxSpMiddle">PWM Freq < 2kHz</p> </td> <td width="44" style="width:32.9pt;border-top:none;border-left:none;border-bottom: solid #009EB8 1.0pt;border-right:solid #009EB8 1.0pt;padding:0cm 5.4pt 0cm 5.4pt; height:17.0pt"> <p class="ListParagraph1CxSpMiddle">--</p> </td> <td width="49" style="width:37.1pt;border-top:none;border-left:none;border-bottom: solid #009EB8 1.0pt;border-right:solid #009EB8 1.0pt;padding:0cm 5.4pt 0cm 5.4pt; height:17.0pt"> <p class="ListParagraph1CxSpMiddle">4096</p> </td> <td width="47" style="width:35.0pt;border-top:none;border-left:none;border-bottom: solid #009EB8 1.0pt;border-right:solid #009EB8 1.0pt;padding:0cm 5.4pt 0cm 5.4pt; height:17.0pt"> <p class="ListParagraph1CxSpMiddle">--</p> </td> <td width="49" rowspan="4" style="width:36.6pt;border-top:none;border-left:none; border-bottom:solid #009EB8 1.0pt;border-right:solid #009EB8 1.0pt; padding:0cm 5.4pt 0cm 5.4pt;height:17.0pt"> <p class="ListParagraph1CxSpLast">Steps</p> </td> </tr> <tr style="height:17.0pt"> <td width="283" style="width:212.05pt;border-top:none;border-left:none; border-bottom:solid #009EB8 1.0pt;border-right:solid #009EB8 1.0pt; padding:0cm 5.4pt 0cm 5.4pt;height:17.0pt"> <p class="ListParagraph1CxSpMiddle">PWM Freq = 2 to 4kHz</p> </td> <td width="44" style="width:32.9pt;border-top:none;border-left:none;border-bottom: solid #009EB8 1.0pt;border-right:solid #009EB8 1.0pt;padding:0cm 5.4pt 0cm 5.4pt; height:17.0pt"> <p class="ListParagraph1CxSpMiddle">--</p> </td> <td width="49" style="width:37.1pt;border-top:none;border-left:none;border-bottom: solid #009EB8 1.0pt;border-right:solid #009EB8 1.0pt;padding:0cm 5.4pt 0cm 5.4pt; height:17.0pt"> <p class="ListParagraph1CxSpMiddle">2048</p> </td> <td width="47" style="width:35.0pt;border-top:none;border-left:none;border-bottom: solid #009EB8 1.0pt;border-right:solid #009EB8 1.0pt;padding:0cm 5.4pt 0cm 5.4pt; height:17.0pt"> <p class="ListParagraph1CxSpMiddle">--</p> </td> </tr> <tr style="height:17.0pt"> <td width="283" style="width:212.05pt;border-top:none;border-left:none; border-bottom:solid #009EB8 1.0pt;border-right:solid #009EB8 1.0pt; padding:0cm 5.4pt 0cm 5.4pt;height:17.0pt"> <p class="ListParagraph1CxSpMiddle">PWM Freq = 4 to 8kHz</p> </td> <td width="44" style="width:32.9pt;border-top:none;border-left:none;border-bottom: solid #009EB8 1.0pt;border-right:solid #009EB8 1.0pt;padding:0cm 5.4pt 0cm 5.4pt; height:17.0pt"> <p class="ListParagraph1CxSpMiddle">--</p> </td> <td width="49" style="width:37.1pt;border-top:none;border-left:none;border-bottom: solid #009EB8 1.0pt;border-right:solid #009EB8 1.0pt;padding:0cm 5.4pt 0cm 5.4pt; height:17.0pt"> <p class="ListParagraph1CxSpMiddle">1024</p> </td> <td width="47" style="width:35.0pt;border-top:none;border-left:none;border-bottom: solid #009EB8 1.0pt;border-right:solid #009EB8 1.0pt;padding:0cm 5.4pt 0cm 5.4pt; height:17.0pt"> <p class="ListParagraph1CxSpMiddle">--</p> </td> </tr> <tr style="height:17.0pt"> <td width="283" style="width:212.05pt;border-top:none;border-left:none; border-bottom:solid #009EB8 1.0pt;border-right:solid #009EB8 1.0pt; padding:0cm 5.4pt 0cm 5.4pt;height:17.0pt"> <p class="ListParagraph1CxSpMiddle">PWM Freq = 8 to 25kHz</p> </td> <td width="44" style="width:32.9pt;border-top:none;border-left:none;border-bottom: solid #009EB8 1.0pt;border-right:solid #009EB8 1.0pt;padding:0cm 5.4pt 0cm 5.4pt; height:17.0pt"> <p class="ListParagraph1CxSpMiddle">--</p> </td> <td width="49" style="width:37.1pt;border-top:none;border-left:none;border-bottom: solid #009EB8 1.0pt;border-right:solid #009EB8 1.0pt;padding:0cm 5.4pt 0cm 5.4pt; height:17.0pt"> <p class="ListParagraph1CxSpMiddle">512</p> </td> <td width="47" style="width:35.0pt;border-top:none;border-left:none;border-bottom: solid #009EB8 1.0pt;border-right:solid #009EB8 1.0pt;padding:0cm 5.4pt 0cm 5.4pt; height:17.0pt"> <p class="ListParagraph1CxSpMiddle">--</p> </td> </tr> </table> </div>

3. Power-up Procedure

<h3>Suggestion Required Equipments</h3> <ul> <li>RT4527A Evaluation Board </li> <li>DC power supply capable of at least 30V and 5A</li> <li>LED Load Board</li> <li>Function Generator</li> <li>Oscilloscope</li> </ul>

4. Quick Start Procedures

<p class="bady">The Evaluation Board is fully assembled and tested. Follow the steps below to verify board operation. Do not turn on supplies until all connections are made. When measuring the output voltage ripple, care must be taken to avoid a long ground lead on the oscilloscope probe. Measure the output voltage ripple by touching the probe tip and ground ring directly across the last output capacitor. </p>

5. Proper measurement equipment setup and follow the procedure below.

<p class="MsoListParagraph">1) With power off, connect the power supply for VIN and GND pins.</p> <p class="MsoListParagraph">2) With power off, use jumper to pull high for EN pin.</p> <p class="MsoListParagraph">3) With power off, connect the Function Generator to PWM pin.</p> <p class="MsoListParagraph">4) With power off, connect the LED Load Board to VOUT and LEDx pins. </p> <p class="MsoListParagraph">5) Turn on the power supply at the input. Make sure that the input voltage does not exceeds 24V on the Evaluation Board.</p> <p class="MsoListParagraph">6) Turn on the Function Generator at the PWM pin.</p> <p class="MsoListParagraph">7) Check LED Load Board brightness.</p> <p class="MsoListParagraph">8) Once the proper output voltage is established, adjust the PWM duty within the operating ranges and observe the output LED brightness, I_CHx, efficiency and other performance.</p>

6. Detailed Description of Hardware

<h3>Headers Description and Placement</h3> <p class="MsoNormal"><a class="fancybox" href="/content/dam/richtek-eds/resources/evaluation-boards/evb_rt4527agqw/html-images/image001_en.jpg"><img width="567" height="407" id="圖片 9" src="/content/dam/richtek-eds/resources/evaluation-boards/evb_rt4527agqw/html-images/image001_en.jpg" alt="一張含有 電路, 電子工程, 電子元件, 電子產品 的圖片 自動產生的描述" /></a></p> <p class="MsoNormal">Carefully inspect all the components used in the EVB according to the following Bill of Materials table, and then make sure all the components are undamaged and correctly installed. If there is any missing or damaged component, which may occur during transportation, please contact our distributors or e-mail us at <a href="mailto:evb_service@richtek.com" class="link">evb_service@richtek.com</a>.</p>

7. Test Points

<p class="MsoNormal">The EVB is provided with the test points and pin names listed in the table below.</p> <table class="MsoTableLightListAccent2" border="1" cellspacing="0" cellpadding="0" width="680" style="width:510.2pt;margin-left:1.85pt;border-collapse:collapse; border:none"> <thead> <tr style="height:1.0cm"> <td width="14%" style="width:14.64%;border:solid #009EB8 1.0pt;background: #009EB8;padding:0cm 5.4pt 0cm 5.4pt;height:1.0cm"> <p class="23CxSpFirst">Test Point/</p> <p class="23CxSpMiddle">Pin Name</p> </td> <td width="85%" style="width:85.36%;border:solid #009EB8 1.0pt;border-left: none;background:#009EB8;padding:0cm 5.4pt 0cm 5.4pt;height:1.0cm"> <p class="23CxSpLast">Function</p> </td> </tr> </thead> <tr style="height:17.0pt"> <td width="14%" style="width:14.64%;border:solid #009EB8 1.0pt;border-top: none;padding:0cm 5.4pt 0cm 5.4pt;height:17.0pt"> <p class="ListParagraph1CxSpFirst">SDA</p> </td> <td width="85%" style="width:85.36%;border-top:none;border-left:none; border-bottom:solid #009EB8 1.0pt;border-right:solid #009EB8 1.0pt; padding:0cm 5.4pt 0cm 5.4pt;height:17.0pt"> <p class="ListParagraph1CxSpLast">Data signal pin of I²C interface.</p> </td> </tr> <tr style="height:17.0pt"> <td width="14%" style="width:14.64%;border:solid #009EB8 1.0pt;border-top: none;padding:0cm 5.4pt 0cm 5.4pt;height:17.0pt"> <p class="ListParagraph1CxSpFirst">SCL</p> </td> <td width="85%" style="width:85.36%;border-top:none;border-left:none; border-bottom:solid #009EB8 1.0pt;border-right:solid #009EB8 1.0pt; padding:0cm 5.4pt 0cm 5.4pt;height:17.0pt"> <p class="ListParagraph1CxSpLast">Clock signal pin of I²C interface.</p> </td> </tr> <tr style="height:17.0pt"> <td width="14%" style="width:14.64%;border:solid #009EB8 1.0pt;border-top: none;padding:0cm 5.4pt 0cm 5.4pt;height:17.0pt"> <p class="ListParagraph1CxSpFirst">VDC</p> </td> <td width="85%" style="width:85.36%;border-top:none;border-left:none; border-bottom:solid #009EB8 1.0pt;border-right:solid #009EB8 1.0pt; padding:0cm 5.4pt 0cm 5.4pt;height:17.0pt"> <p class="ListParagraph1CxSpLast">Output of internal regulator.</p> </td> </tr> <tr style="height:17.0pt"> <td width="14%" style="width:14.64%;border:solid #009EB8 1.0pt;border-top: none;padding:0cm 5.4pt 0cm 5.4pt;height:17.0pt"> <p class="ListParagraph1CxSpFirst">COMP</p> </td> <td width="85%" style="width:85.36%;border-top:none;border-left:none; border-bottom:solid #009EB8 1.0pt;border-right:solid #009EB8 1.0pt; padding:0cm 5.4pt 0cm 5.4pt;height:17.0pt"> <p class="ListParagraph1CxSpLast">Boost external compensator pin.</p> </td> </tr> <tr style="height:17.0pt"> <td width="14%" style="width:14.64%;border:solid #009EB8 1.0pt;border-top: none;padding:0cm 5.4pt 0cm 5.4pt;height:17.0pt"> <p class="ListParagraph1">A0</p> </td> <td width="85%" style="width:85.36%;border-top:none;border-left:none; border-bottom:solid #009EB8 1.0pt;border-right:solid #009EB8 1.0pt; padding:0cm 5.4pt 0cm 5.4pt;height:17.0pt"> <p class="MsoNormal">Device address select (7bits), A0 = 0 (Low) <span lang="EN-US" style="font-family:Wingdings;color:black">à</span> (0x6Ch), A0 = 1 (High) <span lang="EN-US" style="font-family:Wingdings; color:black">à</span> (0x6Eh).</p> </td> </tr> <tr style="height:17.0pt"> <td width="14%" style="width:14.64%;border:solid #009EB8 1.0pt;border-top: none;padding:0cm 5.4pt 0cm 5.4pt;height:17.0pt"> <p class="ListParagraph1CxSpFirst">CH6</p> </td> <td width="85%" style="width:85.36%;border-top:none;border-left:none; border-bottom:solid #009EB8 1.0pt;border-right:solid #009EB8 1.0pt; padding:0cm 5.4pt 0cm 5.4pt;height:17.0pt"> <p class="ListParagraph1CxSpLast"><a name="OLE_LINK8">Current sink for LED6.</a></p> </td> </tr> <tr style="height:17.0pt"> <td width="14%" style="width:14.64%;border:solid #009EB8 1.0pt;border-top: none;padding:0cm 5.4pt 0cm 5.4pt;height:17.0pt"> <p class="ListParagraph1CxSpFirst">CH5</p> </td> <td width="85%" style="width:85.36%;border-top:none;border-left:none; border-bottom:solid #009EB8 1.0pt;border-right:solid #009EB8 1.0pt; padding:0cm 5.4pt 0cm 5.4pt;height:17.0pt"> <p class="ListParagraph1CxSpLast">Current sink for LED5.</p> </td> </tr> <tr style="height:17.0pt"> <td width="14%" style="width:14.64%;border:solid #009EB8 1.0pt;border-top: none;padding:0cm 5.4pt 0cm 5.4pt;height:17.0pt"> <p class="ListParagraph1CxSpFirst">CH4</p> </td> <td width="85%" style="width:85.36%;border-top:none;border-left:none; border-bottom:solid #009EB8 1.0pt;border-right:solid #009EB8 1.0pt; padding:0cm 5.4pt 0cm 5.4pt;height:17.0pt"> <p class="ListParagraph1CxSpLast">Current sink for LED4.</p> </td> </tr> <tr style="height:17.0pt"> <td width="14%" style="width:14.64%;border:solid #009EB8 1.0pt;border-top: none;padding:0cm 5.4pt 0cm 5.4pt;height:17.0pt"> <p class="ListParagraph1CxSpFirst">CH3</p> </td> <td width="85%" style="width:85.36%;border-top:none;border-left:none; border-bottom:solid #009EB8 1.0pt;border-right:solid #009EB8 1.0pt; padding:0cm 5.4pt 0cm 5.4pt;height:17.0pt"> <p class="ListParagraph1CxSpLast">Current sink for LED3.</p> </td> </tr> <tr style="height:17.0pt"> <td width="14%" style="width:14.64%;border:solid #009EB8 1.0pt;border-top: none;padding:0cm 5.4pt 0cm 5.4pt;height:17.0pt"> <p class="ListParagraph1CxSpFirst">CH2</p> </td> <td width="85%" style="width:85.36%;border-top:none;border-left:none; border-bottom:solid #009EB8 1.0pt;border-right:solid #009EB8 1.0pt; padding:0cm 5.4pt 0cm 5.4pt;height:17.0pt"> <p class="ListParagraph1CxSpLast">Current sink for LED2.</p> </td> </tr> <tr style="height:17.0pt"> <td width="14%" style="width:14.64%;border:solid #009EB8 1.0pt;border-top: none;padding:0cm 5.4pt 0cm 5.4pt;height:17.0pt"> <p class="ListParagraph1CxSpFirst">CH1</p> </td> <td width="85%" style="width:85.36%;border-top:none;border-left:none; border-bottom:solid #009EB8 1.0pt;border-right:solid #009EB8 1.0pt; padding:0cm 5.4pt 0cm 5.4pt;height:17.0pt"> <p class="ListParagraph1CxSpLast">Current sink for LED1.</p> </td> </tr> <tr style="height:17.0pt"> <td width="14%" style="width:14.64%;border:solid #009EB8 1.0pt;border-top: none;padding:0cm 5.4pt 0cm 5.4pt;height:17.0pt"> <p class="ListParagraph1CxSpFirst">VOUT</p> </td> <td width="85%" style="width:85.36%;border-top:none;border-left:none; border-bottom:solid #009EB8 1.0pt;border-right:solid #009EB8 1.0pt; padding:0cm 5.4pt 0cm 5.4pt;height:17.0pt"> <p class="ListParagraph1CxSpLast">Output of boost converter.</p> </td> </tr> <tr style="height:17.0pt"> <td width="14%" style="width:14.64%;border:solid #009EB8 1.0pt;border-top: none;padding:0cm 5.4pt 0cm 5.4pt;height:17.0pt"> <p class="ListParagraph1CxSpFirst">PGND</p> </td> <td width="85%" style="width:85.36%;border-top:none;border-left:none; border-bottom:solid #009EB8 1.0pt;border-right:solid #009EB8 1.0pt; padding:0cm 5.4pt 0cm 5.4pt;height:17.0pt"> <p class="ListParagraph1CxSpLast">Power ground.</p> </td> </tr> <tr style="height:17.0pt"> <td width="14%" style="width:14.64%;border:solid #009EB8 1.0pt;border-top: none;padding:0cm 5.4pt 0cm 5.4pt;height:17.0pt"> <p class="ListParagraph1CxSpFirst">LX</p> </td> <td width="85%" style="width:85.36%;border-top:none;border-left:none; border-bottom:solid #009EB8 1.0pt;border-right:solid #009EB8 1.0pt; padding:0cm 5.4pt 0cm 5.4pt;height:17.0pt"> <p class="ListParagraph1CxSpLast">Switch node of boost converter.</p> </td> </tr> <tr style="height:17.0pt"> <td width="14%" style="width:14.64%;border:solid #009EB8 1.0pt;border-top: none;padding:0cm 5.4pt 0cm 5.4pt;height:17.0pt"> <p class="ListParagraph1CxSpFirst">VIN</p> </td> <td width="85%" style="width:85.36%;border-top:none;border-left:none; border-bottom:solid #009EB8 1.0pt;border-right:solid #009EB8 1.0pt; padding:0cm 5.4pt 0cm 5.4pt;height:17.0pt"> <p class="ListParagraph1CxSpLast">Power supply input.</p> </td> </tr> <tr style="height:17.0pt"> <td width="14%" style="width:14.64%;border:solid #009EB8 1.0pt;border-top: none;padding:0cm 5.4pt 0cm 5.4pt;height:17.0pt"> <p class="ListParagraph1CxSpFirst">EN</p> </td> <td width="85%" style="width:85.36%;border-top:none;border-left:none; border-bottom:solid #009EB8 1.0pt;border-right:solid #009EB8 1.0pt; padding:0cm 5.4pt 0cm 5.4pt;height:17.0pt"> <p class="ListParagraph1CxSpLast">Enable control input (active high).</p> </td> </tr> <tr style="height:17.0pt"> <td width="14%" style="width:14.64%;border:solid #009EB8 1.0pt;border-top: none;padding:0cm 5.4pt 0cm 5.4pt;height:17.0pt"> <p class="ListParagraph1CxSpFirst">PWM</p> </td> <td width="85%" style="width:85.36%;border-top:none;border-left:none; border-bottom:solid #009EB8 1.0pt;border-right:solid #009EB8 1.0pt; padding:0cm 5.4pt 0cm 5.4pt;height:17.0pt"> <p class="ListParagraph1CxSpLast">PWM dimming control input.</p> </td> </tr> <tr style="height:1.0cm"> <td width="14%" style="width:14.64%;border:solid #009EB8 1.0pt;border-top: none;padding:0cm 5.4pt 0cm 5.4pt;height:1.0cm"> <p class="ListParagraph1CxSpFirst">AGND</p> </td> <td width="85%" style="width:85.36%;border-top:none;border-left:none; border-bottom:solid #009EB8 1.0pt;border-right:solid #009EB8 1.0pt; padding:0cm 5.4pt 0cm 5.4pt;height:1.0cm"> <p class="ListParagraph1CxSpLast">Analog ground. The exposed pad must be soldered to a large PCB and connect to AGND for maximum power dissipation.</p> </td> </tr> </table>

8. Bill of Materials

<div> <table class="TableNormal" border="1" cellspacing="0" cellpadding="0" width="680" style="border-collapse:collapse;border:none"> <thead> <tr style="height:17.0pt"> <td width="680" colspan="7" style="width:510.2pt;border:solid #009EB8 1.0pt; background:#009EB8;padding:0cm 0cm 0cm 0cm;height:17.0pt"> <p class="TableParagraph">V_IN = 12V, V_OUT = LED Load Board , I_OUT = 20mA</p> </td> </tr> <tr style="height:17.0pt"> <td width="63" style="width:47.35pt;border:solid #009EB8 1.0pt;border-top: none;background:#009EB8;padding:0cm 0cm 0cm 0cm;height:17.0pt"> <p class="TableParagraph">Reference</p> </td> <td width="39" style="width:29.4pt;border-top:none;border-left:none; border-bottom:solid #009EB8 1.0pt;border-right:solid #009EB8 1.0pt; background:#009EB8;padding:0cm 0cm 0cm 0cm;height:17.0pt"> <p class="TableParagraph">Count</p> </td> <td width="175" style="width:130.9pt;border-top:none;border-left:none; border-bottom:solid #009EB8 1.0pt;border-right:solid #009EB8 1.0pt; background:#009EB8;padding:0cm 0cm 0cm 0cm;height:17.0pt"> <p class="TableParagraph">Part Number</p> </td> <td width="79" style="width:59.15pt;border-top:none;border-left:none; border-bottom:solid #009EB8 1.0pt;border-right:solid #009EB8 1.0pt; background:#009EB8;padding:0cm 0cm 0cm 0cm;height:17.0pt"> <p class="TableParagraph">Value</p> </td> <td width="131" style="width:98.3pt;border-top:none;border-left:none; border-bottom:solid #009EB8 1.0pt;border-right:solid #009EB8 1.0pt; background:#009EB8;padding:0cm 0cm 0cm 0cm;height:17.0pt"> <p class="TableParagraph">Description</p> </td> <td width="105" style="width:78.4pt;border-top:none;border-left:none; border-bottom:solid #009EB8 1.0pt;border-right:solid #009EB8 1.0pt; background:#009EB8;padding:0cm 0cm 0cm 0cm;height:17.0pt"> <p class="TableParagraph">Package</p> </td> <td width="89" style="width:66.7pt;border-top:none;border-left:none; border-bottom:solid #009EB8 1.0pt;border-right:solid #009EB8 1.0pt; background:#009EB8;padding:0cm 0cm 0cm 0cm;height:17.0pt"> <p class="TableParagraph">Manufacturer</p> </td> </tr> </thead> <tr style="height:1.0cm"> <td width="63" style="width:47.35pt;border:solid #009EB8 1.0pt;border-top:none; padding:0cm 0cm 0cm 0cm;height:1.0cm"> <p class="MsoNormal">U2</p> </td> <td width="39" style="width:29.4pt;border-top:none;border-left:none;border-bottom: solid #009EB8 1.0pt;border-right:solid #009EB8 1.0pt;padding:0cm 0cm 0cm 0cm; height:1.0cm"> <p class="MsoNormal">1</p> </td> <td width="175" style="width:130.9pt;border-top:none;border-left:none; border-bottom:solid #009EB8 1.0pt;border-right:solid #009EB8 1.0pt; padding:0cm 0cm 0cm 0cm;height:1.0cm"> <p class="MsoNormal">RT4527AGQW</p> </td> <td width="79" style="width:59.15pt;border-top:none;border-left:none; border-bottom:solid #009EB8 1.0pt;border-right:solid #009EB8 1.0pt; padding:0cm 0cm 0cm 0cm;height:1.0cm"> <p class="MsoNormal">RT4527A</p> </td> <td width="131" style="width:98.3pt;border-top:none;border-left:none; border-bottom:solid #009EB8 1.0pt;border-right:solid #009EB8 1.0pt; padding:0cm 0cm 0cm 0cm;height:1.0cm"> <p class="MsoNormal">LED Driver</p> </td> <td width="105" style="width:78.4pt;border-top:none;border-left:none; border-bottom:solid #009EB8 1.0pt;border-right:solid #009EB8 1.0pt; padding:0cm 0cm 0cm 0cm;height:1.0cm"> <p class="MsoNormal">WQFN-20L 3.5x3.5</p> </td> <td width="89" style="width:66.7pt;border-top:none;border-left:none;border-bottom: solid #009EB8 1.0pt;border-right:solid #009EB8 1.0pt;padding:0cm 0cm 0cm 0cm; height:1.0cm"> <p class="MsoNormal">RICHTEK</p> </td> </tr> <tr style="height:1.0cm"> <td width="63" style="width:47.35pt;border:solid #009EB8 1.0pt;border-top:none; padding:0cm 0cm 0cm 0cm;height:1.0cm"> <p class="MsoNormal">C4</p> </td> <td width="39" style="width:29.4pt;border-top:none;border-left:none;border-bottom: solid #009EB8 1.0pt;border-right:solid #009EB8 1.0pt;padding:0cm 0cm 0cm 0cm; height:1.0cm"> <p class="MsoNormal">1</p> </td> <td width="175" style="width:130.9pt;border-top:none;border-left:none; border-bottom:solid #009EB8 1.0pt;border-right:solid #009EB8 1.0pt; padding:0cm 0cm 0cm 0cm;height:1.0cm"> <p class="MsoNormal">0603B104K500CT</p> </td> <td width="79" style="width:59.15pt;border-top:none;border-left:none; border-bottom:solid #009EB8 1.0pt;border-right:solid #009EB8 1.0pt; padding:0cm 0cm 0cm 0cm;height:1.0cm"> <p class="MsoNormal">100nF</p> </td> <td width="131" style="width:98.3pt;border-top:none;border-left:none; border-bottom:solid #009EB8 1.0pt;border-right:solid #009EB8 1.0pt; padding:0cm 0cm 0cm 0cm;height:1.0cm"> <p class="MsoNormal">Capacitor, Ceramic</p> <p class="MsoNormal">50V/X7R</p> </td> <td width="105" style="width:78.4pt;border-top:none;border-left:none; border-bottom:solid #009EB8 1.0pt;border-right:solid #009EB8 1.0pt; padding:0cm 0cm 0cm 0cm;height:1.0cm"> <p class="MsoNormal">0603</p> </td> <td width="89" style="width:66.7pt;border-top:none;border-left:none;border-bottom: solid #009EB8 1.0pt;border-right:solid #009EB8 1.0pt;padding:0cm 0cm 0cm 0cm; height:1.0cm"> <p class="MsoNormal">WALSIN</p> </td> </tr> <tr style="height:1.0cm"> <td width="63" style="width:47.35pt;border:solid #009EB8 1.0pt;border-top:none; padding:0cm 0cm 0cm 0cm;height:1.0cm"> <p class="MsoNormal">C12</p> </td> <td width="39" style="width:29.4pt;border-top:none;border-left:none;border-bottom: solid #009EB8 1.0pt;border-right:solid #009EB8 1.0pt;padding:0cm 0cm 0cm 0cm; height:1.0cm"> <p class="MsoNormal">1</p> </td> <td width="175" style="width:130.9pt;border-top:none;border-left:none; border-bottom:solid #009EB8 1.0pt;border-right:solid #009EB8 1.0pt; padding:0cm 0cm 0cm 0cm;height:1.0cm"> <p class="MsoNormal">1206B105K500CT</p> </td> <td width="79" style="width:59.15pt;border-top:none;border-left:none; border-bottom:solid #009EB8 1.0pt;border-right:solid #009EB8 1.0pt; padding:0cm 0cm 0cm 0cm;height:1.0cm"> <p class="MsoNormal">1µF</p> </td> <td width="131" style="width:98.3pt;border-top:none;border-left:none; border-bottom:solid #009EB8 1.0pt;border-right:solid #009EB8 1.0pt; padding:0cm 0cm 0cm 0cm;height:1.0cm"> <p class="MsoNormal">Capacitor, Ceramic<br /> 50V/X7R</p> </td> <td width="105" style="width:78.4pt;border-top:none;border-left:none; border-bottom:solid #009EB8 1.0pt;border-right:solid #009EB8 1.0pt; padding:0cm 0cm 0cm 0cm;height:1.0cm"> <p class="MsoNormal">1206</p> </td> <td width="89" style="width:66.7pt;border-top:none;border-left:none;border-bottom: solid #009EB8 1.0pt;border-right:solid #009EB8 1.0pt;padding:0cm 0cm 0cm 0cm; height:1.0cm"> <p class="MsoNormal">WALSIN</p> </td> </tr> <tr style="height:1.0cm"> <td width="63" style="width:47.35pt;border:solid #009EB8 1.0pt;border-top:none; padding:0cm 0cm 0cm 0cm;height:1.0cm"> <p class="MsoNormal">C15</p> </td> <td width="39" style="width:29.4pt;border-top:none;border-left:none;border-bottom: solid #009EB8 1.0pt;border-right:solid #009EB8 1.0pt;padding:0cm 0cm 0cm 0cm; height:1.0cm"> <p class="MsoNormal">1</p> </td> <td width="175" style="width:130.9pt;border-top:none;border-left:none; border-bottom:solid #009EB8 1.0pt;border-right:solid #009EB8 1.0pt; padding:0cm 0cm 0cm 0cm;height:1.0cm"> <p class="MsoNormal">0603B102K500CT</p> </td> <td width="79" style="width:59.15pt;border-top:none;border-left:none; border-bottom:solid #009EB8 1.0pt;border-right:solid #009EB8 1.0pt; padding:0cm 0cm 0cm 0cm;height:1.0cm"> <p class="MsoNormal">1nF</p> </td> <td width="131" style="width:98.3pt;border-top:none;border-left:none; border-bottom:solid #009EB8 1.0pt;border-right:solid #009EB8 1.0pt; padding:0cm 0cm 0cm 0cm;height:1.0cm"> <p class="MsoNormal">Capacitor, Ceramic</p> <p class="MsoNormal">50V/X7R</p> </td> <td width="105" style="width:78.4pt;border-top:none;border-left:none; border-bottom:solid #009EB8 1.0pt;border-right:solid #009EB8 1.0pt; padding:0cm 0cm 0cm 0cm;height:1.0cm"> <p class="MsoNormal">0603</p> </td> <td width="89" style="width:66.7pt;border-top:none;border-left:none;border-bottom: solid #009EB8 1.0pt;border-right:solid #009EB8 1.0pt;padding:0cm 0cm 0cm 0cm; height:1.0cm"> <p class="MsoNormal">WALSIN</p> </td> </tr> <tr style="height:1.0cm"> <td width="63" style="width:47.35pt;border:solid #009EB8 1.0pt;border-top:none; padding:0cm 0cm 0cm 0cm;height:1.0cm"> <p class="MsoNormal">COUT1,</p> <p class="MsoNormal">CVIN1</p> </td> <td width="39" style="width:29.4pt;border-top:none;border-left:none;border-bottom: solid #009EB8 1.0pt;border-right:solid #009EB8 1.0pt;padding:0cm 0cm 0cm 0cm; height:1.0cm"> <p class="MsoNormal">2</p> </td> <td width="175" style="width:130.9pt;border-top:none;border-left:none; border-bottom:solid #009EB8 1.0pt;border-right:solid #009EB8 1.0pt; padding:0cm 0cm 0cm 0cm;height:1.0cm"> <p class="MsoNormal">UMK316AB7475KL-T</p> </td> <td width="79" style="width:59.15pt;border-top:none;border-left:none; border-bottom:solid #009EB8 1.0pt;border-right:solid #009EB8 1.0pt; padding:0cm 0cm 0cm 0cm;height:1.0cm"> <p class="MsoNormal">4.7µF</p> </td> <td width="131" style="width:98.3pt;border-top:none;border-left:none; border-bottom:solid #009EB8 1.0pt;border-right:solid #009EB8 1.0pt; padding:0cm 0cm 0cm 0cm;height:1.0cm"> <p class="MsoNormal">Capacitor, Ceramic</p> <p class="MsoNormal">50V/X7R</p> </td> <td width="105" style="width:78.4pt;border-top:none;border-left:none; border-bottom:solid #009EB8 1.0pt;border-right:solid #009EB8 1.0pt; padding:0cm 0cm 0cm 0cm;height:1.0cm"> <p class="MsoNormal">1206</p> </td> <td width="89" style="width:66.7pt;border-top:none;border-left:none;border-bottom: solid #009EB8 1.0pt;border-right:solid #009EB8 1.0pt;padding:0cm 0cm 0cm 0cm; height:1.0cm"> <p class="MsoNormal">TAIYO YUDEN</p> </td> </tr> <tr style="height:17.0pt"> <td width="63" style="width:47.35pt;border:solid #009EB8 1.0pt;border-top:none; padding:0cm 0cm 0cm 0cm;height:17.0pt"> <p class="MsoNormal">D2</p> </td> <td width="39" style="width:29.4pt;border-top:none;border-left:none;border-bottom: solid #009EB8 1.0pt;border-right:solid #009EB8 1.0pt;padding:0cm 0cm 0cm 0cm; height:17.0pt"> <p class="MsoNormal">1</p> </td> <td width="175" style="width:130.9pt;border-top:none;border-left:none; border-bottom:solid #009EB8 1.0pt;border-right:solid #009EB8 1.0pt; padding:0cm 0cm 0cm 0cm;height:17.0pt"> <p class="MsoNormal">SR26</p> </td> <td width="79" style="width:59.15pt;border-top:none;border-left:none; border-bottom:solid #009EB8 1.0pt;border-right:solid #009EB8 1.0pt; padding:0cm 0cm 0cm 0cm;height:17.0pt"> <p class="MsoNormal">60V/2A</p> </td> <td width="131" style="width:98.3pt;border-top:none;border-left:none; border-bottom:solid #009EB8 1.0pt;border-right:solid #009EB8 1.0pt; padding:0cm 0cm 0cm 0cm;height:17.0pt"> <p class="MsoNormal">D-SMA_DO-214AC</p> </td> <td width="105" style="width:78.4pt;border-top:none;border-left:none; border-bottom:solid #009EB8 1.0pt;border-right:solid #009EB8 1.0pt; padding:0cm 0cm 0cm 0cm;height:17.0pt"> <p class="MsoNormal">SMA/DO-214AC</p> </td> <td width="89" style="width:66.7pt;border-top:none;border-left:none;border-bottom: solid #009EB8 1.0pt;border-right:solid #009EB8 1.0pt;padding:0cm 0cm 0cm 0cm; height:17.0pt"> <p class="MsoNormal">PAN JIT</p> </td> </tr> <tr style="height:1.0cm"> <td width="63" style="width:47.35pt;border:solid #009EB8 1.0pt;border-top:none; padding:0cm 0cm 0cm 0cm;height:1.0cm"> <p class="MsoNormal">L1</p> </td> <td width="39" style="width:29.4pt;border-top:none;border-left:none;border-bottom: solid #009EB8 1.0pt;border-right:solid #009EB8 1.0pt;padding:0cm 0cm 0cm 0cm; height:1.0cm"> <p class="MsoNormal">1</p> </td> <td width="175" style="width:130.9pt;border-top:none;border-left:none; border-bottom:solid #009EB8 1.0pt;border-right:solid #009EB8 1.0pt; padding:0cm 0cm 0cm 0cm;height:1.0cm"> <p class="MsoNormal">LSXNH8080YKL100MJG</p> </td> <td width="79" style="width:59.15pt;border-top:none;border-left:none; border-bottom:solid #009EB8 1.0pt;border-right:solid #009EB8 1.0pt; padding:0cm 0cm 0cm 0cm;height:1.0cm"> <p class="MsoNormal">10µH</p> </td> <td width="131" style="width:98.3pt;border-top:none;border-left:none; border-bottom:solid #009EB8 1.0pt;border-right:solid #009EB8 1.0pt; padding:0cm 0cm 0cm 0cm;height:1.0cm"> <p class="MsoNormal">L-8x8</p> </td> <td width="105" style="width:78.4pt;border-top:none;border-left:none; border-bottom:solid #009EB8 1.0pt;border-right:solid #009EB8 1.0pt; padding:0cm 0cm 0cm 0cm;height:1.0cm"> </td> <td width="89" style="width:66.7pt;border-top:none;border-left:none;border-bottom: solid #009EB8 1.0pt;border-right:solid #009EB8 1.0pt;padding:0cm 0cm 0cm 0cm; height:1.0cm"> <p class="MsoNormal">TAIYO YUDEN</p> </td> </tr> <tr style="height:1.0cm"> <td width="63" style="width:47.35pt;border:solid #009EB8 1.0pt;border-top:none; padding:0cm 0cm 0cm 0cm;height:1.0cm"> <p class="MsoNormal">R2, R7</p> </td> <td width="39" style="width:29.4pt;border-top:none;border-left:none;border-bottom: solid #009EB8 1.0pt;border-right:solid #009EB8 1.0pt;padding:0cm 0cm 0cm 0cm; height:1.0cm"> <p class="MsoNormal">2</p> </td> <td width="175" style="width:130.9pt;border-top:none;border-left:none; border-bottom:solid #009EB8 1.0pt;border-right:solid #009EB8 1.0pt; padding:0cm 0cm 0cm 0cm;height:1.0cm"> <p class="MsoNormal">WR06X1001FTL</p> </td> <td width="79" style="width:59.15pt;border-top:none;border-left:none; border-bottom:solid #009EB8 1.0pt;border-right:solid #009EB8 1.0pt; padding:0cm 0cm 0cm 0cm;height:1.0cm"> <p class="MsoNormal">1k</p> </td> <td width="131" style="width:98.3pt;border-top:none;border-left:none; border-bottom:solid #009EB8 1.0pt;border-right:solid #009EB8 1.0pt; padding:0cm 0cm 0cm 0cm;height:1.0cm"> <p class="MsoNormal">Resistor, Chip</p> <p class="MsoNormal">0603</p> </td> <td width="105" style="width:78.4pt;border-top:none;border-left:none; border-bottom:solid #009EB8 1.0pt;border-right:solid #009EB8 1.0pt; padding:0cm 0cm 0cm 0cm;height:1.0cm"> <p class="MsoNormal">0603</p> </td> <td width="89" style="width:66.7pt;border-top:none;border-left:none;border-bottom: solid #009EB8 1.0pt;border-right:solid #009EB8 1.0pt;padding:0cm 0cm 0cm 0cm; height:1.0cm"> <p class="MsoNormal">WALSIN</p> </td> </tr> <tr style="height:39.7pt"> <td width="63" style="width:47.35pt;border:solid #009EB8 1.0pt;border-top:none; padding:0cm 0cm 0cm 0cm;height:39.7pt"> <p class="MsoNormal">R8, R9, R10, R20, R21, R25</p> </td> <td width="39" style="width:29.4pt;border-top:none;border-left:none;border-bottom: solid #009EB8 1.0pt;border-right:solid #009EB8 1.0pt;padding:0cm 0cm 0cm 0cm; height:39.7pt"> <p class="MsoNormal">6</p> </td> <td width="175" style="width:130.9pt;border-top:none;border-left:none; border-bottom:solid #009EB8 1.0pt;border-right:solid #009EB8 1.0pt; padding:0cm 0cm 0cm 0cm;height:39.7pt"> <p class="MsoNormal">WR06X000 PTL</p> </td> <td width="79" style="width:59.15pt;border-top:none;border-left:none; border-bottom:solid #009EB8 1.0pt;border-right:solid #009EB8 1.0pt; padding:0cm 0cm 0cm 0cm;height:39.7pt"> <p class="MsoNormal">0</p> </td> <td width="131" style="width:98.3pt;border-top:none;border-left:none; border-bottom:solid #009EB8 1.0pt;border-right:solid #009EB8 1.0pt; padding:0cm 0cm 0cm 0cm;height:39.7pt"> <p class="MsoNormal">Resistor, Chip</p> <p class="MsoNormal">0603</p> </td> <td width="105" style="width:78.4pt;border-top:none;border-left:none; border-bottom:solid #009EB8 1.0pt;border-right:solid #009EB8 1.0pt; padding:0cm 0cm 0cm 0cm;height:39.7pt"> <p class="MsoNormal">0603</p> </td> <td width="89" style="width:66.7pt;border-top:none;border-left:none;border-bottom: solid #009EB8 1.0pt;border-right:solid #009EB8 1.0pt;padding:0cm 0cm 0cm 0cm; height:39.7pt"> <p class="MsoNormal">WALSIN</p> </td> </tr> <tr style="height:1.0cm"> <td width="63" style="width:47.35pt;border:solid #009EB8 1.0pt;border-top:none; padding:0cm 0cm 0cm 0cm;height:1.0cm"> <p class="MsoNormal">R11, R12</p> </td> <td width="39" style="width:29.4pt;border-top:none;border-left:none;border-bottom: solid #009EB8 1.0pt;border-right:solid #009EB8 1.0pt;padding:0cm 0cm 0cm 0cm; height:1.0cm"> <p class="MsoNormal">2</p> </td> <td width="175" style="width:130.9pt;border-top:none;border-left:none; border-bottom:solid #009EB8 1.0pt;border-right:solid #009EB8 1.0pt; padding:0cm 0cm 0cm 0cm;height:1.0cm"> <p class="MsoNormal">WR06X4701FTL</p> </td> <td width="79" style="width:59.15pt;border-top:none;border-left:none; border-bottom:solid #009EB8 1.0pt;border-right:solid #009EB8 1.0pt; padding:0cm 0cm 0cm 0cm;height:1.0cm"> <p class="MsoNormal">4.7k</p> </td> <td width="131" style="width:98.3pt;border-top:none;border-left:none; border-bottom:solid #009EB8 1.0pt;border-right:solid #009EB8 1.0pt; padding:0cm 0cm 0cm 0cm;height:1.0cm"> <p class="MsoNormal">Resistor, Chip</p> <p class="MsoNormal">0603</p> </td> <td width="105" style="width:78.4pt;border-top:none;border-left:none; border-bottom:solid #009EB8 1.0pt;border-right:solid #009EB8 1.0pt; padding:0cm 0cm 0cm 0cm;height:1.0cm"> <p class="MsoNormal">0603</p> </td> <td width="89" style="width:66.7pt;border-top:none;border-left:none;border-bottom: solid #009EB8 1.0pt;border-right:solid #009EB8 1.0pt;padding:0cm 0cm 0cm 0cm; height:1.0cm"> <p class="MsoNormal">WALSIN</p> </td> </tr> <tr style="height:1.0cm"> <td width="63" style="width:47.35pt;border:solid #009EB8 1.0pt;border-top:none; padding:0cm 0cm 0cm 0cm;height:1.0cm"> <p class="MsoNormal">R19</p> </td> <td width="39" style="width:29.4pt;border-top:none;border-left:none;border-bottom: solid #009EB8 1.0pt;border-right:solid #009EB8 1.0pt;padding:0cm 0cm 0cm 0cm; height:1.0cm"> <p class="MsoNormal">1</p> </td> <td width="175" style="width:130.9pt;border-top:none;border-left:none; border-bottom:solid #009EB8 1.0pt;border-right:solid #009EB8 1.0pt; padding:0cm 0cm 0cm 0cm;height:1.0cm"> <p class="MsoNormal">RTT05000JTP</p> </td> <td width="79" style="width:59.15pt;border-top:none;border-left:none; border-bottom:solid #009EB8 1.0pt;border-right:solid #009EB8 1.0pt; padding:0cm 0cm 0cm 0cm;height:1.0cm"> <p class="MsoNormal">0</p> </td> <td width="131" style="width:98.3pt;border-top:none;border-left:none; border-bottom:solid #009EB8 1.0pt;border-right:solid #009EB8 1.0pt; padding:0cm 0cm 0cm 0cm;height:1.0cm"> <p class="MsoNormal">Resistor, Chip</p> <p class="MsoNormal">0805</p> </td> <td width="105" style="width:78.4pt;border-top:none;border-left:none; border-bottom:solid #009EB8 1.0pt;border-right:solid #009EB8 1.0pt; padding:0cm 0cm 0cm 0cm;height:1.0cm"> <p class="MsoNormal">0805</p> </td> <td width="89" style="width:66.7pt;border-top:none;border-left:none;border-bottom: solid #009EB8 1.0pt;border-right:solid #009EB8 1.0pt;padding:0cm 0cm 0cm 0cm; height:1.0cm"> <p class="MsoNormal">RALEC</p> </td> </tr> <tr style="height:1.0cm"> <td width="63" style="width:47.35pt;border:solid #009EB8 1.0pt;border-top:none; padding:0cm 0cm 0cm 0cm;height:1.0cm"> <p class="MsoNormal">R26</p> </td> <td width="39" style="width:29.4pt;border-top:none;border-left:none;border-bottom: solid #009EB8 1.0pt;border-right:solid #009EB8 1.0pt;padding:0cm 0cm 0cm 0cm; height:1.0cm"> <p class="MsoNormal">1</p> </td> <td width="175" style="width:130.9pt;border-top:none;border-left:none; border-bottom:solid #009EB8 1.0pt;border-right:solid #009EB8 1.0pt; padding:0cm 0cm 0cm 0cm;height:1.0cm"> <p class="MsoNormal">WR06X10R0FTL</p> </td> <td width="79" style="width:59.15pt;border-top:none;border-left:none; border-bottom:solid #009EB8 1.0pt;border-right:solid #009EB8 1.0pt; padding:0cm 0cm 0cm 0cm;height:1.0cm"> <p class="MsoNormal">10</p> </td> <td width="131" style="width:98.3pt;border-top:none;border-left:none; border-bottom:solid #009EB8 1.0pt;border-right:solid #009EB8 1.0pt; padding:0cm 0cm 0cm 0cm;height:1.0cm"> <p class="MsoNormal">Resistor, Chip</p> <p class="MsoNormal">0603</p> </td> <td width="105" style="width:78.4pt;border-top:none;border-left:none; border-bottom:solid #009EB8 1.0pt;border-right:solid #009EB8 1.0pt; padding:0cm 0cm 0cm 0cm;height:1.0cm"> <p class="MsoNormal">0603</p> </td> <td width="89" style="width:66.7pt;border-top:none;border-left:none;border-bottom: solid #009EB8 1.0pt;border-right:solid #009EB8 1.0pt;padding:0cm 0cm 0cm 0cm; height:1.0cm"> <p class="MsoNormal">WALSIN</p> </td> </tr> </table> </div>

9. Typical Applications

<h3>EVB Schematic Diagram</h3> <p class="MsoNormal"><a class="fancybox" href="/content/dam/richtek-eds/resources/evaluation-boards/evb_rt4527agqw/html-images/image002_en.png"><img border="0" width="684" height="401" id="Picture 3" src="/content/dam/richtek-eds/resources/evaluation-boards/evb_rt4527agqw/html-images/image002_en.png" alt="Technical Document Image Preview" /></a></p> <p class="MsoNormal">1. The capacitance values of the input and output capacitors will influence the input and output voltage ripple. </p> <p class="MsoNormal">2. MLCC capacitors have degrading capacitance at DC bias voltage, and especially smaller size MLCC capacitors will have much lower capacitance. </p>

10. Measure Result

<table class="MsoNormalTable" border="1" cellspacing="0" cellpadding="0" style="margin-left:26.35pt;border-collapse:collapse;border:none"> <tr> <td width="306" style="width:229.8pt;border:solid #009EB8 1.0pt;background: #009EB8;padding:0cm 5.4pt 0cm 5.4pt"> <p class="MsoNormal">Quiescent Current vs. Input Voltage</p> </td> <td width="307" style="width:230.35pt;border:solid #009EB8 1.0pt;border-left: none;background:#009EB8;padding:0cm 5.4pt 0cm 5.4pt"> <p class="MsoNormal">Switching Frequency vs. Temperature</p> </td> </tr> <tr style="height:168.2pt"> <td width="306" style="width:229.8pt;border:solid #009EB8 1.0pt;border-top: none;padding:0cm 5.4pt 0cm 5.4pt;height:168.2pt"> <p class="MsoNormal"><a class="fancybox" href="/content/dam/richtek-eds/resources/evaluation-boards/evb_rt4527agqw/html-images/image003_en.png"><img border="0" width="251" height="198" id="圖片 1" src="/content/dam/richtek-eds/resources/evaluation-boards/evb_rt4527agqw/html-images/image003_en.png" alt="Technical Document Image Preview" /></a></p> </td> <td width="307" style="width:230.35pt;border-top:none;border-left:none; border-bottom:solid #009EB8 1.0pt;border-right:solid #009EB8 1.0pt; padding:0cm 5.4pt 0cm 5.4pt;height:168.2pt"> <p class="MsoNormal"><a class="fancybox" href="/content/dam/richtek-eds/resources/evaluation-boards/evb_rt4527agqw/html-images/image004_en.png"><img border="0" width="259" height="201" id="圖片 14" src="/content/dam/richtek-eds/resources/evaluation-boards/evb_rt4527agqw/html-images/image004_en.png" alt="Technical Document Image Preview" /></a></p> </td> </tr> <tr> <td width="306" style="width:229.8pt;border:solid #009EB8 1.0pt;border-top: none;background:#009EB8;padding:0cm 5.4pt 0cm 5.4pt"> <p class="MsoNormal">Switching Frequency vs. Input Voltage </p> </td> <td width="307" style="width:230.35pt;border-top:none;border-left:none; border-bottom:solid #009EB8 1.0pt;border-right:solid #009EB8 1.0pt; background:#009EB8;padding:0cm 5.4pt 0cm 5.4pt"> <p class="MsoNormal">Channel Output Current vs. CHx</p> </td> </tr> <tr style="height:172.95pt"> <td width="306" style="width:229.8pt;border:solid #009EB8 1.0pt;border-top: none;padding:0cm 5.4pt 0cm 5.4pt;height:172.95pt"> <p class="MsoNormal"><a class="fancybox" href="/content/dam/richtek-eds/resources/evaluation-boards/evb_rt4527agqw/html-images/image005_en.png"><img border="0" width="292" height="227" id="圖片 18" src="/content/dam/richtek-eds/resources/evaluation-boards/evb_rt4527agqw/html-images/image005_en.png" alt="Technical Document Image Preview" /></a></p> </td> <td width="307" style="width:230.35pt;border-top:none;border-left:none; border-bottom:solid #009EB8 1.0pt;border-right:solid #009EB8 1.0pt; padding:0cm 5.4pt 0cm 5.4pt;height:172.95pt"> <p class="MsoNormal"><a class="fancybox" href="/content/dam/richtek-eds/resources/evaluation-boards/evb_rt4527agqw/html-images/image006_en.png"><img border="0" width="293" height="235" id="圖片 22" src="/content/dam/richtek-eds/resources/evaluation-boards/evb_rt4527agqw/html-images/image006_en.png" alt="Technical Document Image Preview" /></a></p> </td> </tr> <tr> <td width="306" style="width:229.8pt;border:solid #009EB8 1.0pt;border-top: none;background:#009EB8;padding:0cm 5.4pt 0cm 5.4pt"> <p class="MsoNormal">LED Current vs. PWM Duty_ PWM Mode</p> </td> <td width="307" style="width:230.35pt;border-top:none;border-left:none; border-bottom:solid #009EB8 1.0pt;border-right:solid #009EB8 1.0pt; background:#009EB8;padding:0cm 5.4pt 0cm 5.4pt"> <p class="MsoNormal">LED Current vs. PWM Duty_ DC Mode</p> </td> </tr> <tr> <td width="306" style="width:229.8pt;border:solid #009EB8 1.0pt;border-top: none;padding:0cm 1.4pt 0cm 1.4pt"> <p class="MsoNormal"><a class="fancybox" href="/content/dam/richtek-eds/resources/evaluation-boards/evb_rt4527agqw/html-images/image007_en.png"><img border="0" width="303" height="240" id="圖片 24" src="/content/dam/richtek-eds/resources/evaluation-boards/evb_rt4527agqw/html-images/image007_en.png" alt="Technical Document Image Preview" /></a></p> </td> <td width="307" style="width:230.35pt;border-top:none;border-left:none; border-bottom:solid #009EB8 1.0pt;border-right:solid #009EB8 1.0pt; padding:0cm 1.4pt 0cm 1.4pt"> <p class="MsoNormal"><a class="fancybox" href="/content/dam/richtek-eds/resources/evaluation-boards/evb_rt4527agqw/html-images/image008_en.png"><img border="0" width="303" height="243" id="圖片 25" src="/content/dam/richtek-eds/resources/evaluation-boards/evb_rt4527agqw/html-images/image008_en.png" alt="Technical Document Image Preview" /></a></p> </td> </tr> </table> <table class="MsoNormalTable" border="1" cellspacing="0" cellpadding="0" style="margin-left:26.35pt;border-collapse:collapse;border:none"> <tr> <td width="306" style="width:229.8pt;border:solid #009EB8 1.0pt;background: #009EB8;padding:0cm 5.4pt 0cm 5.4pt"> <p class="MsoNormal">LED Current vs. PWM Duty_ MIX Mode</p> </td> <td width="307" style="width:230.35pt;border:solid #009EB8 1.0pt;border-left: none;background:#009EB8;padding:0cm 5.4pt 0cm 5.4pt"> <p class="MsoNormal">LED Current vs. PWM Duty_ MIX-26K Mode</p> </td> </tr> <tr style="height:184.2pt"> <td width="306" style="width:229.8pt;border:solid #009EB8 1.0pt;border-top: none;padding:0cm 1.4pt 0cm 1.4pt;height:184.2pt"> <p class="MsoNormal"><a class="fancybox" href="/content/dam/richtek-eds/resources/evaluation-boards/evb_rt4527agqw/html-images/image009_en.png"><img border="0" width="303" height="237" id="圖片 26" src="/content/dam/richtek-eds/resources/evaluation-boards/evb_rt4527agqw/html-images/image009_en.png" alt="Technical Document Image Preview" /></a></p> </td> <td width="307" style="width:230.35pt;border-top:none;border-left:none; border-bottom:solid #009EB8 1.0pt;border-right:solid #009EB8 1.0pt; padding:0cm 1.4pt 0cm 1.4pt;height:184.2pt"> <p class="MsoNormal"><a class="fancybox" href="/content/dam/richtek-eds/resources/evaluation-boards/evb_rt4527agqw/html-images/image010_en.png"><img border="0" width="303" height="235" id="圖片 27" src="/content/dam/richtek-eds/resources/evaluation-boards/evb_rt4527agqw/html-images/image010_en.png" alt="Technical Document Image Preview" /></a></p> </td> </tr> <tr> <td width="306" style="width:229.8pt;border:solid #009EB8 1.0pt;border-top: none;background:#009EB8;padding:0cm 5.4pt 0cm 5.4pt"> <p class="MsoNormal">Power On from EN</p> </td> <td width="307" style="width:230.35pt;border-top:none;border-left:none; border-bottom:solid #009EB8 1.0pt;border-right:solid #009EB8 1.0pt; background:#009EB8;padding:0cm 5.4pt 0cm 5.4pt"> <p class="MsoNormal">Power Off from EN</p> </td> </tr> <tr> <td width="306" style="width:229.8pt;border:solid #009EB8 1.0pt;border-top: none;padding:0cm 5.4pt 0cm 5.4pt"> <p class="MsoNormal"><a class="fancybox" href="/content/dam/richtek-eds/resources/evaluation-boards/evb_rt4527agqw/html-images/image011_en.png"><img border="0" width="292" height="212" id="圖片 28" src="/content/dam/richtek-eds/resources/evaluation-boards/evb_rt4527agqw/html-images/image011_en.png" alt="Technical Document Image Preview" /></a></p> </td> <td width="307" style="width:230.35pt;border-top:none;border-left:none; border-bottom:solid #009EB8 1.0pt;border-right:solid #009EB8 1.0pt; padding:0cm 5.4pt 0cm 5.4pt"> <p class="MsoNormal"><a class="fancybox" href="/content/dam/richtek-eds/resources/evaluation-boards/evb_rt4527agqw/html-images/image012_en.png"><img border="0" width="293" height="209" id="圖片 29" src="/content/dam/richtek-eds/resources/evaluation-boards/evb_rt4527agqw/html-images/image012_en.png" alt="Technical Document Image Preview" /></a></p> </td> </tr> </table>

11. Evaluation Board Layout

<p class="bady">Figure 1 to Figure 4 are RT4527A Evaluation Board layout. This board size is 70mmx50mm and is constructed on four-layer PCB, outer layers with 2 oz. Cu and inner layers with 1 oz. Cu.</p> <p class="23CxSpFirst"><a class="fancybox" href="/content/dam/richtek-eds/resources/evaluation-boards/evb_rt4527agqw/html-images/image013_en.jpg"><img border="0" width="491" height="355" id="圖片 3" src="/content/dam/richtek-eds/resources/evaluation-boards/evb_rt4527agqw/html-images/image013_en.jpg" alt="一張含有 文字, 電子工程, 電路, 螢幕擷取畫面 的圖片 自動產生的描述" /></a></p> <p class="23CxSpLast">Figure 1. Top View (1^st layer)</p> <p class="MsoNormal"><a class="fancybox" href="/content/dam/richtek-eds/resources/evaluation-boards/evb_rt4527agqw/html-images/image014_en.jpg"><img border="0" width="491" height="354" id="圖片 4" src="/content/dam/richtek-eds/resources/evaluation-boards/evb_rt4527agqw/html-images/image014_en.jpg" alt="一張含有 螢幕擷取畫面, 文字, Rectangle, 數字 的圖片 自動產生的描述" /></a></p> <p class="10">Figure 2. PCB Layout—Inner Side (2^nd Layer)</p> <p class="MsoNormal"><a class="fancybox" href="/content/dam/richtek-eds/resources/evaluation-boards/evb_rt4527agqw/html-images/image015_en.jpg"><img border="0" width="491" height="355" id="圖片 5" src="/content/dam/richtek-eds/resources/evaluation-boards/evb_rt4527agqw/html-images/image015_en.jpg" alt="一張含有 螢幕擷取畫面, 文字, Rectangle, 平行 的圖片 自動產生的描述" /></a></p> <p class="10">Figure 3. PCB Layout—Inner Side (3^rd Layer)</p> <p class="MsoNormal"><a class="fancybox" href="/content/dam/richtek-eds/resources/evaluation-boards/evb_rt4527agqw/html-images/image016_en.jpg"><img border="0" width="491" height="354" id="圖片 6" src="/content/dam/richtek-eds/resources/evaluation-boards/evb_rt4527agqw/html-images/image016_en.jpg" alt="一張含有 螢幕擷取畫面, 圖表, 數字, 圓形 的圖片 自動產生的描述" /></a></p> <p class="10">Figure 4. Bottom View (4^th Layer)</p>