overview

1. Purpose

<p class="MsoNormal">The RT8555 is a 36V High Efficiency Boost Converter with I²C Controlled 6-CH LED Driver. This document explains the function and use of the RT8555 evaluation board (EVB) and provides information to enable operation and modification of the evaluation board and circuit to suit individual requirements.</p> <h1> </h1>

2. Introduction

<h2> </h2> <h3>General Product Information</h3> <p class="bady">The RT8555 is a 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. The internal current sinks support a maximum of ±2% current mismatching for excellent brightness uniformity in each string of LEDs. To provide enough headroom for current sink operation, the Boost controller monitors the minimum voltage of the feedback pins and regulates an optimized output voltage for power efficiency.</p> <p class="bady">The RT8555 has a wide input voltage operating range from 2.7V to 24V and contains I²C interface for controlling the dimming mode, operating frequency and the LED current. The internal 100mΩ, 36V power switch with current-mode control provides over-current protection. The switching frequency of the RT8555 is adjustable from 300kHz to 2MHz, which allows flexibility between efficiency and component size.</p> <p class="bady">The RT8555 is available in the WL-CSP-20B 1.65 x 2.05 (BSC), with pitch 0.4mm package.</p> <p class="bady"> </p> <h3>Product Feature</h3> <ul> <li> Wide Operating Input Voltage : 2.7V to 24V </li> <li> High Output Voltage : Up to 36V </li> <li> Programmable Channel Current : 10mA to 35mA </li> <li> Channel Current Regulation with Accuracy ±3% and Matching ±2% </li> <li> Dimming Controls </li> ► Direct PWM Dimming up to 20kHz and Minimum On-Time to 400ns <br /> ► PWM to Analog Dimming up to 20kHz with 8-bit <li> I²C Programs LED Current, Switching Frequency, Dimming Mode </li> <li> Switching Frequency : 300kHz to 2MHz </li> <li> Current Limit, Over-Temperature Protection and Over-Voltage Protection </li> <li> Input Under-Voltage Lockout </li> <li> RoHS Compliant and Halogen Free </li> </ul>

3. Key Performance Summary Table

<table width="680" class="MsoTableLightListAccent2" style="border: currentColor; width: 510.2pt; border-collapse: collapse;" border="1" cellspacing="0" cellpadding="0"> <tbody> <tr style="height: 17pt;"> <td style="background: #009eb8; padding: 0cm 5.4pt; border: 1pt solid #009eb8; width: 35.78%; height: 17pt;"> <p class="ListParagraph1CxSpFirst">Key Features</p> </td> <td style="background: #009eb8; border-width: 1pt 1pt 1pt medium; border-style: solid solid solid none; border-color: #009eb8 #009eb8 #009eb8 currentColor; padding: 0cm 5.4pt; width: 64.22%; height: 17pt;"> <p class="ListParagraph1CxSpLast">Evaluation Board Number : PCB025_V1</p> </td> </tr> <tr style="height: 17pt;"> <td style="border-width: medium 1pt 1pt; border-style: none solid solid; border-color: currentColor #009eb8 #009eb8; padding: 0cm 5.4pt; width: 35.78%; height: 17pt;"> <p class="ListParagraph1CxSpFirst">Default Input Voltage</p> </td> <td style="border-width: medium 1pt 1pt medium; border-style: none solid solid none; border-color: currentColor #009eb8 #009eb8 currentColor; padding: 0cm 5.4pt; width: 64.22%; height: 17pt;"> <p class="ListParagraph1CxSpLast">3.8V</p> </td> </tr> <tr style="height: 17pt;"> <td style="border-width: medium 1pt 1pt; border-style: none solid solid; border-color: currentColor #009eb8 #009eb8; padding: 0cm 5.4pt; width: 35.78%; height: 17pt;"> <p class="ListParagraph1CxSpFirst">Default OVP</p> </td> <td style="border-width: medium 1pt 1pt medium; border-style: none solid solid none; border-color: currentColor #009eb8 #009eb8 currentColor; padding: 0cm 5.4pt; width: 64.22%; height: 17pt;"> <p class="ListParagraph1CxSpLast">36V</p> </td> </tr> <tr style="height: 17pt;"> <td style="border-width: medium 1pt 1pt; border-style: none solid solid; border-color: currentColor #009eb8 #009eb8; padding: 0cm 5.4pt; width: 35.78%; height: 17pt;"> <p class="ListParagraph1CxSpFirst">Default Per Channel Output Current</p> </td> <td style="border-width: medium 1pt 1pt medium; border-style: none solid solid none; border-color: currentColor #009eb8 #009eb8 currentColor; padding: 0cm 5.4pt; width: 64.22%; height: 17pt;"> <p class="ListParagraph1CxSpLast">20mA</p> </td> </tr> <tr style="height: 17pt;"> <td style="border-width: medium 1pt 1pt; border-style: none solid solid; border-color: currentColor #009eb8 #009eb8; padding: 0cm 5.4pt; width: 35.78%; height: 17pt;"> <p class="ListParagraph1CxSpFirst">Default Marking & Package Type</p> </td> <td style="border-width: medium 1pt 1pt medium; border-style: none solid solid none; border-color: currentColor #009eb8 #009eb8 currentColor; padding: 0cm 5.4pt; width: 64.22%; height: 17pt;"> <p class="ListParagraph1CxSpLast">RT8555WSC, WL-CSP-20B 1.65 x 2.05 (BSC)</p> </td> </tr> <tr style="height: 17pt;"> <td style="border-width: medium 1pt 1pt; border-style: none solid solid; border-color: currentColor #009eb8 #009eb8; padding: 0cm 5.4pt; width: 35.78%; height: 17pt;"> <p class="ListParagraph1CxSpFirst">Operation Frequency</p> </td> <td style="border-width: medium 1pt 1pt medium; border-style: none solid solid none; border-color: currentColor #009eb8 #009eb8 currentColor; padding: 0cm 5.4pt; width: 64.22%; height: 17pt;"> <p class="ListParagraph1CxSpLast">900kHz</p> </td> </tr> <tr style="height: 51pt;"> <td style="border-width: medium 1pt 1pt; border-style: none solid solid; border-color: currentColor #009eb8 #009eb8; padding: 0cm 5.4pt; width: 35.78%; height: 51pt;"> <p class="ListParagraph1CxSpFirst">Other Key Features</p> </td> <td style="border-width: medium 1pt 1pt medium; border-style: none solid solid none; border-color: currentColor #009eb8 #009eb8 currentColor; padding: 0cm 5.4pt; width: 64.22%; height: 51pt;"> <p class="ListParagraph1CxSpMiddle">2.7V to 24V Input Voltage Range</p> <p class="ListParagraph1CxSpMiddle">Programmable LED Current, Switching Frequency, Dimming Mode</p> <p class="ListParagraph1CxSpMiddle">Output Over-Voltage Protection, Current Limit, Thermal Shutdown</p> <p class="ListParagraph1CxSpLast">20-Ball WL-CSP, with pitch 0.4mm Package</p> </td> </tr> </tbody> </table> <p class="MsoNormal"> </p>

4. Bench Test Setup Conditions

<h3>Headers Description and Placement</h3> <p class="MsoNormal"><a href="/content/dam/richtek-eds/resources/evaluation-boards/evb_rt8555wsc/html-images/image001_en.jpg" class="fancybox"><img width="397" height="284" width="397" height="284" id="圖片 6" alt="Technical Document Image Preview" src="/content/dam/richtek-eds/resources/evaluation-boards/evb_rt8555wsc/html-images/image001_en.jpg" /></a></p> <p class="2">Please carefully inspect the EVB IC and external components, comparing them to the following Bill of Materials, to ensure that all components are installed and undamaged. If any components are missing or damaged during transportation, please contact the distributor or send e-mail to <a href="mailto:evb_service@richtek.com" class="link">evb_service@richtek.com</a></p> <p class="2"><span style="text-decoration: underline;"><br /> </span></p> <h3>Test Points</h3> <p class="MsoNormal">The EVB is provided with the test points and pin names listed in the table below..</p> <table width="680" class="MsoTableLightListAccent2" style="border: currentColor; width: 510.2pt; border-collapse: collapse;" border="1" cellspacing="0" cellpadding="0"> <tbody> <tr style="height: 1cm;"> <td style="background: #009eb8; padding: 0cm 5.4pt; border: 1pt solid #009eb8; width: 13.56%; height: 1cm;"> <p class="23CxSpFirst">Test point/</p> <p class="23CxSpMiddle">Pin name</p> </td> <td style="background: #009eb8; border-width: 1pt 1pt 1pt medium; border-style: solid solid solid none; border-color: #009eb8 #009eb8 #009eb8 currentColor; padding: 0cm 5.4pt; width: 25.02%; height: 1cm;"> <p class="23CxSpMiddle">Signal</p> </td> <td style="background: #009eb8; border-width: 1pt 1pt 1pt medium; border-style: solid solid solid none; border-color: #009eb8 #009eb8 #009eb8 currentColor; padding: 0cm 5.4pt; width: 61.42%; height: 1cm;"> <p class="23CxSpLast">Comment (expected waveforms or voltage levels on test points)</p> </td> </tr> <tr style="height: 17pt;"> <td style="border-width: medium 1pt 1pt; border-style: none solid solid; border-color: currentColor #009eb8 #009eb8; padding: 0cm 5.4pt; width: 13.56%; height: 17pt;"> <p class="ListParagraph1CxSpFirst">VIN</p> </td> <td style="border-width: medium 1pt 1pt medium; border-style: none solid solid none; border-color: currentColor #009eb8 #009eb8 currentColor; padding: 0cm 5.4pt; width: 25.02%; height: 17pt;"> <p class="ListParagraph1CxSpMiddle">Input voltage</p> </td> <td style="border-width: medium 1pt 1pt medium; border-style: none solid solid none; border-color: currentColor #009eb8 #009eb8 currentColor; padding: 0cm 5.4pt; width: 61.42%; height: 17pt;"> <p class="ListParagraph1CxSpLast">Boost conveter input voltage.</p> </td> </tr> <tr style="height: 17pt;"> <td style="border-width: medium 1pt 1pt; border-style: none solid solid; border-color: currentColor #009eb8 #009eb8; padding: 0cm 5.4pt; width: 13.56%; height: 17pt;"> <p class="ListParagraph1CxSpFirst">VIN_1</p> </td> <td style="border-width: medium 1pt 1pt medium; border-style: none solid solid none; border-color: currentColor #009eb8 #009eb8 currentColor; padding: 0cm 5.4pt; width: 25.02%; height: 17pt;"> <p class="ListParagraph1CxSpMiddle">Input voltage</p> </td> <td style="border-width: medium 1pt 1pt medium; border-style: none solid solid none; border-color: currentColor #009eb8 #009eb8 currentColor; padding: 0cm 5.4pt; width: 61.42%; height: 17pt;"> <p class="ListParagraph1CxSpLast">RT8555 VIN input voltage. Connected to VIN through R1.</p> </td> </tr> <tr style="height: 1cm;"> <td style="border-width: medium 1pt 1pt; border-style: none solid solid; border-color: currentColor #009eb8 #009eb8; padding: 0cm 5.4pt; width: 13.56%; height: 1cm;"> <p class="ListParagraph1CxSpFirst">VOUT</p> </td> <td style="border-width: medium 1pt 1pt medium; border-style: none solid solid none; border-color: currentColor #009eb8 #009eb8 currentColor; padding: 0cm 5.4pt; width: 25.02%; height: 1cm;"> <p class="ListParagraph1CxSpMiddle">Output voltage </p> </td> <td style="border-width: medium 1pt 1pt medium; border-style: none solid solid none; border-color: currentColor #009eb8 #009eb8 currentColor; padding: 0cm 5.4pt; width: 61.42%; height: 1cm;"> <p class="ListParagraph1CxSpLast">Output voltage up to 36V. Drive LED light bars by VOUT connect to FB1 ~ FB6.</p> </td> </tr> <tr style="height: 17pt;"> <td style="border-width: medium 1pt 1pt; border-style: none solid solid; border-color: currentColor #009eb8 #009eb8; padding: 0cm 5.4pt; width: 13.56%; height: 17pt;"> <p class="ListParagraph1CxSpFirst">LX</p> </td> <td style="border-width: medium 1pt 1pt medium; border-style: none solid solid none; border-color: currentColor #009eb8 #009eb8 currentColor; padding: 0cm 5.4pt; width: 25.02%; height: 17pt;"> <p class="ListParagraph1CxSpMiddle">Switching node test point</p> </td> <td style="border-width: medium 1pt 1pt medium; border-style: none solid solid none; border-color: currentColor #009eb8 #009eb8 currentColor; padding: 0cm 5.4pt; width: 61.42%; height: 17pt;"> <p class="ListParagraph1CxSpLast">LX waveform</p> </td> </tr> <tr style="height: 39.7pt;"> <td style="border-width: medium 1pt 1pt; border-style: none solid solid; border-color: currentColor #009eb8 #009eb8; padding: 0cm 5.4pt; width: 13.56%; height: 39.7pt;"> <p class="ListParagraph1CxSpFirst">EN</p> </td> <td style="border-width: medium 1pt 1pt medium; border-style: none solid solid none; border-color: currentColor #009eb8 #009eb8 currentColor; padding: 0cm 5.4pt; width: 25.02%; height: 39.7pt;"> <p class="ListParagraph1CxSpMiddle">Enable input</p> </td> <td style="border-width: medium 1pt 1pt medium; border-style: none solid solid none; border-color: currentColor #009eb8 #009eb8 currentColor; padding: 0cm 5.4pt; width: 61.42%; height: 39.7pt;"> <p class="ListParagraph1CxSpLast">Enable signal. Connecting this pin to pull high enable operation; floating this EN pin or connecting this pin to GND can disable the device.</p> </td> </tr> <tr style="height: 17pt;"> <td style="border-width: medium 1pt 1pt; border-style: none solid solid; border-color: currentColor #009eb8 #009eb8; padding: 0cm 5.4pt; width: 13.56%; height: 17pt;"> <p class="ListParagraph1CxSpFirst">PWM</p> </td> <td style="border-width: medium 1pt 1pt medium; border-style: none solid solid none; border-color: currentColor #009eb8 #009eb8 currentColor; padding: 0cm 5.4pt; width: 25.02%; height: 17pt;"> <p class="ListParagraph1CxSpLast">PWM input</p> </td> <td style="border-width: medium 1pt 1pt medium; border-style: none solid solid none; border-color: currentColor #009eb8 #009eb8 currentColor; padding: 0cm 5.4pt; width: 61.42%; height: 17pt;"> <p class="MsoNormal">PWM Dimming Control Input.</p> </td> </tr> <tr style="height: 1cm;"> <td style="border-width: medium 1pt 1pt; border-style: none solid solid; border-color: currentColor #009eb8 #009eb8; padding: 0cm 5.4pt; width: 13.56%; height: 1cm;"> <p class="ListParagraph1CxSpFirst">FB1 ~ FB6</p> </td> <td style="border-width: medium 1pt 1pt medium; border-style: none solid solid none; border-color: currentColor #009eb8 #009eb8 currentColor; padding: 0cm 5.4pt; width: 25.02%; height: 1cm;"> <p class="ListParagraph1CxSpMiddle">FB pin</p> </td> <td style="border-width: medium 1pt 1pt medium; border-style: none solid solid none; border-color: currentColor #009eb8 #009eb8 currentColor; padding: 0cm 5.4pt; width: 61.42%; height: 1cm;"> <p class="ListParagraph1CxSpLast">Current Sink for LED1 ~ LED6. Drive LED light bars by VOUT connect to FB1 ~ FB6.</p> </td> </tr> <tr style="height: 17pt;"> <td style="border-width: medium 1pt 1pt; border-style: none solid solid; border-color: currentColor #009eb8 #009eb8; padding: 0cm 5.4pt; width: 13.56%; height: 17pt;"> <p class="ListParagraph1CxSpFirst">VCP</p> </td> <td style="border-width: medium 1pt 1pt medium; border-style: none solid solid none; border-color: currentColor #009eb8 #009eb8 currentColor; padding: 0cm 5.4pt; width: 25.02%; height: 17pt;"> <p class="ListParagraph1CxSpMiddle">Internal regulator</p> </td> <td style="border-width: medium 1pt 1pt medium; border-style: none solid solid none; border-color: currentColor #009eb8 #009eb8 currentColor; padding: 0cm 5.4pt; width: 61.42%; height: 17pt;"> <p class="ListParagraph1CxSpLast">LDO Output of Internal Regulator.</p> </td> </tr> <tr style="height: 17pt;"> <td style="border-width: medium 1pt 1pt; border-style: none solid solid; border-color: currentColor #009eb8 #009eb8; padding: 0cm 5.4pt; width: 13.56%; height: 17pt;"> <p class="ListParagraph1CxSpFirst">GND</p> </td> <td style="border-width: medium 1pt 1pt medium; border-style: none solid solid none; border-color: currentColor #009eb8 #009eb8 currentColor; padding: 0cm 5.4pt; width: 25.02%; height: 17pt;"> <p class="ListParagraph1CxSpMiddle">Ground</p> </td> <td style="border-width: medium 1pt 1pt medium; border-style: none solid solid none; border-color: currentColor #009eb8 #009eb8 currentColor; padding: 0cm 5.4pt; width: 61.42%; height: 17pt;"> <p class="ListParagraph1CxSpLast">Ground.</p> </td> </tr> <tr style="height: 17pt;"> <td style="border-width: medium 1pt 1pt; border-style: none solid solid; border-color: currentColor #009eb8 #009eb8; padding: 0cm 5.4pt; width: 13.56%; height: 17pt;"> <p class="ListParagraph1CxSpFirst">SDA</p> </td> <td style="border-width: medium 1pt 1pt medium; border-style: none solid solid none; border-color: currentColor #009eb8 #009eb8 currentColor; padding: 0cm 5.4pt; width: 25.02%; height: 17pt;"> <p class="ListParagraph1CxSpMiddle">Data signal</p> </td> <td style="border-width: medium 1pt 1pt medium; border-style: none solid solid none; border-color: currentColor #009eb8 #009eb8 currentColor; padding: 0cm 5.4pt; width: 61.42%; height: 17pt;"> <p class="ListParagraph1CxSpLast">Data Signal Input of I²C Interface.</p> </td> </tr> <tr style="height: 17pt;"> <td style="border-width: medium 1pt 1pt; border-style: none solid solid; border-color: currentColor #009eb8 #009eb8; padding: 0cm 5.4pt; width: 13.56%; height: 17pt;"> <p class="ListParagraph1CxSpFirst">SCL</p> </td> <td style="border-width: medium 1pt 1pt medium; border-style: none solid solid none; border-color: currentColor #009eb8 #009eb8 currentColor; padding: 0cm 5.4pt; width: 25.02%; height: 17pt;"> <p class="ListParagraph1CxSpMiddle">Clock signal</p> </td> <td style="border-width: medium 1pt 1pt medium; border-style: none solid solid none; border-color: currentColor #009eb8 #009eb8 currentColor; padding: 0cm 5.4pt; width: 61.42%; height: 17pt;"> <p class="ListParagraph1CxSpLast">Clock Signal Input of I²C Interface.</p> </td> </tr> <tr style="height: 17pt;"> <td style="border-width: medium 1pt 1pt; border-style: none solid solid; border-color: currentColor #009eb8 #009eb8; padding: 0cm 5.4pt; width: 13.56%; height: 17pt;"> <p class="ListParagraph1CxSpFirst">JP2</p> </td> <td style="border-width: medium 1pt 1pt medium; border-style: none solid solid none; border-color: currentColor #009eb8 #009eb8 currentColor; padding: 0cm 5.4pt; width: 25.02%; height: 17pt;"> <p class="ListParagraph1CxSpMiddle">Chip enable control</p> </td> <td style="border-width: medium 1pt 1pt medium; border-style: none solid solid none; border-color: currentColor #009eb8 #009eb8 currentColor; padding: 0cm 5.4pt; width: 61.42%; height: 17pt;"> <p class="ListParagraph1CxSpLast">Install jumper or drive EN directly to enable or disable operation.</p> </td> </tr> <tr style="height: 17pt;"> <td style="border-width: medium 1pt 1pt; border-style: none solid solid; border-color: currentColor #009eb8 #009eb8; padding: 0cm 5.4pt; width: 13.56%; height: 17pt;"> <p class="ListParagraph1CxSpFirst">JP5</p> </td> <td style="border-width: medium 1pt 1pt medium; border-style: none solid solid none; border-color: currentColor #009eb8 #009eb8 currentColor; padding: 0cm 5.4pt; width: 25.02%; height: 17pt;"> <p class="ListParagraph1CxSpMiddle">PWM control</p> </td> <td style="border-width: medium 1pt 1pt medium; border-style: none solid solid none; border-color: currentColor #009eb8 #009eb8 currentColor; padding: 0cm 5.4pt; width: 61.42%; height: 17pt;"> <p class="ListParagraph1CxSpLast">Install jumper or drive PWM signal directly to operation.</p> </td> </tr> </tbody> </table> <p class="MsoNormal"> </p>

5. Power-up & Measurement Procedure

<p class="MsoListParagraph">1. Connect input power and input ground to VIN and GND test pins respectively.</p> <p class="MsoListParagraph">2. Connect LED ligh bars to VOUT and FB1 ~ FB6 test pins respectively.</p> <p class="MsoListParagraph">3. There is a 3- pin header “EN” for enable control. To use a jumper at “H” option to tie EN test pin to input power VIN for enabling the device. Inversely, to use a jumper at “L” option to tie EN test pin and ground GND for disabling the device.</p> <p class="MsoListParagraph">4. There is a 3- pin header “PWM” for PWM dimming control. To use a jumper at “H” option to tie PWM test pin to input power VIN for PWM = 100% dimming the device. Inversely, to use a jumper at “L” option to tie PWM test pin and ground GND for PWM = 0% dimming the device.</p> <p class="MsoListParagraph">5. Usually use Function Generator to produce PWM signal to PWM dimming RT8555 ILED current. </p> <p class="MsoListParagraph">6. Input PWM frequency about 200Hz ~ 20kHz.</p> <p class="MsoListParagraph">7. For detailed RT8555 function operation, please reference RT8555 datasheet. </p> <p class="MsoListParagraph"> </p>

6. Schematic, Bill of Materials & Board Layout

<h2> </h2> <h3>EVB Schematic Diagram</h3> <p class="MsoNormal"><a href="/content/dam/richtek-eds/resources/evaluation-boards/evb_rt8555wsc/html-images/image002_en.jpg" class="fancybox"><img width="681" height="408" width="681" height="408" id="圖片 2" style="border-width: 0px; border-style: solid;" alt="Technical Document Image Preview" src="/content/dam/richtek-eds/resources/evaluation-boards/evb_rt8555wsc/html-images/image002_en.jpg" /></a></p> <p class="21"> </p>

7. Bill of Materials

<table width="680" class="MsoTableLightListAccent2" style="border: currentColor; border-collapse: collapse;" border="1" cellspacing="0" cellpadding="0"> <tbody> <tr style="height: 17pt;"> <td style="background: #009eb8; padding: 0cm 5.4pt; border: 1pt solid #009eb8; width: 20.8%; height: 17pt;"> <p class="MsoNormal">Reference</p> </td> <td style="background: #009eb8; border-width: 1pt 1pt 1pt medium; border-style: solid solid solid none; border-color: #009eb8 #009eb8 #009eb8 currentColor; padding: 0cm 5.4pt; width: 5.26%; height: 17pt;"> <p class="MsoNormal">Qty</p> </td> <td style="background: #009eb8; border-width: 1pt 1pt 1pt medium; border-style: solid solid solid none; border-color: #009eb8 #009eb8 #009eb8 currentColor; padding: 0cm 5.4pt; width: 25%; height: 17pt;"> <p class="MsoNormal">Part number</p> </td> <td style="background: #009eb8; border-width: 1pt 1pt 1pt medium; border-style: solid solid solid none; border-color: #009eb8 #009eb8 #009eb8 currentColor; padding: 0cm 5.4pt; width: 19.48%; height: 17pt;"> <p class="MsoNormal">Description</p> </td> <td style="background: #009eb8; border-width: 1pt 1pt 1pt medium; border-style: solid solid solid none; border-color: #009eb8 #009eb8 #009eb8 currentColor; padding: 0cm 5.4pt; width: 15.28%; height: 17pt;"> <p class="MsoNormal">Package</p> </td> <td style="background: #009eb8; border-width: 1pt 1pt 1pt medium; border-style: solid solid solid none; border-color: #009eb8 #009eb8 #009eb8 currentColor; padding: 0cm 5.4pt; width: 14.18%; height: 17pt;"> <p class="MsoNormal">Manufacture</p> </td> </tr> <tr style="height: 39.7pt;"> <td style="border-width: medium 1pt 1pt; border-style: none solid solid; border-color: currentColor #009eb8 #009eb8; padding: 0cm 5.4pt; width: 20.8%; height: 39.7pt;"> <p class="MsoNormal">U2</p> </td> <td style="border-width: medium 1pt 1pt medium; border-style: none solid solid none; border-color: currentColor #009eb8 #009eb8 currentColor; padding: 0cm 5.4pt; width: 5.26%; height: 39.7pt;"> <p class="MsoNormal">1</p> </td> <td style="border-width: medium 1pt 1pt medium; border-style: none solid solid none; border-color: currentColor #009eb8 #009eb8 currentColor; padding: 0cm 5.4pt; width: 25%; height: 39.7pt;"> <p class="MsoNormal">RT8555</p> </td> <td style="border-width: medium 1pt 1pt medium; border-style: none solid solid none; border-color: currentColor #009eb8 #009eb8 currentColor; padding: 0cm 5.4pt; width: 19.48%; height: 39.7pt;"> <p class="MsoNormal">LED Driver</p> </td> <td style="border-width: medium 1pt 1pt medium; border-style: none solid solid none; border-color: currentColor #009eb8 #009eb8 currentColor; padding: 0cm 5.4pt; width: 15.28%; height: 39.7pt;"> <p class="MsoNormal">WL-CSP-20B 1.65 x 2.05 (BSC)</p> </td> <td style="border-width: medium 1pt 1pt medium; border-style: none solid solid none; border-color: currentColor #009eb8 #009eb8 currentColor; padding: 0cm 5.4pt; width: 14.18%; height: 39.7pt;"> <p class="MsoNormal">RICHTEK</p> </td> </tr> <tr style="height: 17pt;"> <td style="border-width: medium 1pt 1pt; border-style: none solid solid; border-color: currentColor #009eb8 #009eb8; padding: 0cm 5.4pt; width: 20.8%; height: 17pt;"> <p class="MsoNormal">C1, CCP</p> </td> <td style="border-width: medium 1pt 1pt medium; border-style: none solid solid none; border-color: currentColor #009eb8 #009eb8 currentColor; padding: 0cm 5.4pt; width: 5.26%; height: 17pt;"> <p class="MsoNormal">1</p> </td> <td style="border-width: medium 1pt 1pt medium; border-style: none solid solid none; border-color: currentColor #009eb8 #009eb8 currentColor; padding: 0cm 5.4pt; width: 25%; height: 17pt;"> <p class="MsoNormal">C2012X7R1E105KT</p> </td> <td style="border-width: medium 1pt 1pt medium; border-style: none solid solid none; border-color: currentColor #009eb8 #009eb8 currentColor; padding: 0cm 5.4pt; width: 19.48%; height: 17pt;"> <p class="MsoNormal">1µF/50V/X7R</p> <p class="MsoNormal">Ceramic Capacitor</p> </td> <td style="border-width: medium 1pt 1pt medium; border-style: none solid solid none; border-color: currentColor #009eb8 #009eb8 currentColor; padding: 0cm 5.4pt; width: 15.28%; height: 17pt;"> <p class="MsoNormal">0805</p> </td> <td style="border-width: medium 1pt 1pt medium; border-style: none solid solid none; border-color: currentColor #009eb8 #009eb8 currentColor; padding: 0cm 5.4pt; width: 14.18%; height: 17pt;"> <p class="MsoNormal">TDK</p> </td> </tr> <tr style="height: 1cm;"> <td style="border-width: medium 1pt 1pt; border-style: none solid solid; border-color: currentColor #009eb8 #009eb8; padding: 0cm 5.4pt; width: 20.8%; height: 1cm;"> <p class="MsoNormal">CIN3</p> </td> <td style="border-width: medium 1pt 1pt medium; border-style: none solid solid none; border-color: currentColor #009eb8 #009eb8 currentColor; padding: 0cm 5.4pt; width: 5.26%; height: 1cm;"> <p class="MsoNormal">1</p> </td> <td style="border-width: medium 1pt 1pt medium; border-style: none solid solid none; border-color: currentColor #009eb8 #009eb8 currentColor; padding: 0cm 5.4pt; width: 25%; height: 1cm;"> <p class="MsoNormal">GRM31CR71H475KA12L</p> </td> <td style="border-width: medium 1pt 1pt medium; border-style: none solid solid none; border-color: currentColor #009eb8 #009eb8 currentColor; padding: 0cm 5.4pt; width: 19.48%; height: 1cm;"> <p class="MsoNormal">4.7µF/50V/X7R</p> <p class="MsoNormal">Ceramic Capacitor</p> </td> <td style="border-width: medium 1pt 1pt medium; border-style: none solid solid none; border-color: currentColor #009eb8 #009eb8 currentColor; padding: 0cm 5.4pt; width: 15.28%; height: 1cm;"> <p class="MsoNormal">1210</p> </td> <td style="border-width: medium 1pt 1pt medium; border-style: none solid solid none; border-color: currentColor #009eb8 #009eb8 currentColor; padding: 0cm 5.4pt; width: 14.18%; height: 1cm;"> <p class="MsoNormal">Murata</p> </td> </tr> <tr style="height: 1cm;"> <td style="border-width: medium 1pt 1pt; border-style: none solid solid; border-color: currentColor #009eb8 #009eb8; padding: 0cm 5.4pt; width: 20.8%; height: 1cm;"> <p class="MsoNormal">COUT2, COUT3, COUT4</p> </td> <td style="border-width: medium 1pt 1pt medium; border-style: none solid solid none; border-color: currentColor #009eb8 #009eb8 currentColor; padding: 0cm 5.4pt; width: 5.26%; height: 1cm;"> <p class="MsoNormal">3</p> </td> <td style="border-width: medium 1pt 1pt medium; border-style: none solid solid none; border-color: currentColor #009eb8 #009eb8 currentColor; padding: 0cm 5.4pt; width: 25%; height: 1cm;"> <p class="MsoNormal">UMK316BJ225KD-T</p> </td> <td style="border-width: medium 1pt 1pt medium; border-style: none solid solid none; border-color: currentColor #009eb8 #009eb8 currentColor; padding: 0cm 5.4pt; width: 19.48%; height: 1cm;"> <p class="MsoNormal">2.2µF/50V/X5R</p> <p class="MsoNormal">Ceramic Capacitor</p> </td> <td style="border-width: medium 1pt 1pt medium; border-style: none solid solid none; border-color: currentColor #009eb8 #009eb8 currentColor; padding: 0cm 5.4pt; width: 15.28%; height: 1cm;"> <p class="MsoNormal">1206</p> </td> <td style="border-width: medium 1pt 1pt medium; border-style: none solid solid none; border-color: currentColor #009eb8 #009eb8 currentColor; padding: 0cm 5.4pt; width: 14.18%; height: 1cm;"> <p class="MsoNormal">TAIYO</p> </td> </tr> <tr style="height: 17pt;"> <td style="border-width: medium 1pt 1pt; border-style: none solid solid; border-color: currentColor #009eb8 #009eb8; padding: 0cm 5.4pt; width: 20.8%; height: 17pt;"> <p class="MsoNormal">D2</p> </td> <td style="border-width: medium 1pt 1pt medium; border-style: none solid solid none; border-color: currentColor #009eb8 #009eb8 currentColor; padding: 0cm 5.4pt; width: 5.26%; height: 17pt;"> <p class="MsoNormal">1</p> </td> <td style="border-width: medium 1pt 1pt medium; border-style: none solid solid none; border-color: currentColor #009eb8 #009eb8 currentColor; padding: 0cm 5.4pt; width: 25%; height: 17pt;"> <p class="MsoNormal">SR26</p> </td> <td style="border-width: medium 1pt 1pt medium; border-style: none solid solid none; border-color: currentColor #009eb8 #009eb8 currentColor; padding: 0cm 5.4pt; width: 19.48%; height: 17pt;"> <p class="MsoNormal">Schottky diodes</p> </td> <td style="border-width: medium 1pt 1pt medium; border-style: none solid solid none; border-color: currentColor #009eb8 #009eb8 currentColor; padding: 0cm 5.4pt; width: 15.28%; height: 17pt;"> <p class="MsoNormal">SMB/DO-214</p> </td> <td style="border-width: medium 1pt 1pt medium; border-style: none solid solid none; border-color: currentColor #009eb8 #009eb8 currentColor; padding: 0cm 5.4pt; width: 14.18%; height: 17pt;"> <p class="MsoNormal">PANJIT</p> </td> </tr> <tr style="height: 39.7pt;"> <td style="border-width: medium 1pt 1pt; border-style: none solid solid; border-color: currentColor #009eb8 #009eb8; padding: 0cm 5.4pt; width: 20.8%; height: 39.7pt;"> <p class="MsoNormal">L1</p> </td> <td style="border-width: medium 1pt 1pt medium; border-style: none solid solid none; border-color: currentColor #009eb8 #009eb8 currentColor; padding: 0cm 5.4pt; width: 5.26%; height: 39.7pt;"> <p class="MsoNormal">1</p> </td> <td style="border-width: medium 1pt 1pt medium; border-style: none solid solid none; border-color: currentColor #009eb8 #009eb8 currentColor; padding: 0cm 5.4pt; width: 25%; height: 39.7pt;"> <p class="MsoNormal">NR8040T6R8N</p> </td> <td style="border-width: medium 1pt 1pt medium; border-style: none solid solid none; border-color: currentColor #009eb8 #009eb8 currentColor; padding: 0cm 5.4pt; width: 19.48%; height: 39.7pt;"> <p class="MsoNormal">6.8μH/3.4A</p> <p class="MsoNormal"> DCR = 25mΩ, Inductor</p> </td> <td style="border-width: medium 1pt 1pt medium; border-style: none solid solid none; border-color: currentColor #009eb8 #009eb8 currentColor; padding: 0cm 5.4pt; width: 15.28%; height: 39.7pt;"> <p class="MsoNormal">L-NR8040</p> </td> <td style="border-width: medium 1pt 1pt medium; border-style: none solid solid none; border-color: currentColor #009eb8 #009eb8 currentColor; padding: 0cm 5.4pt; width: 14.18%; height: 39.7pt;"> <p class="MsoNormal">TAIYO </p> </td> </tr> <tr style="height: 17pt;"> <td style="border-width: medium 1pt 1pt; border-style: none solid solid; border-color: currentColor #009eb8 #009eb8; padding: 0cm 5.4pt; width: 20.8%; height: 17pt;"> <p class="MsoNormal">R1</p> </td> <td style="border-width: medium 1pt 1pt medium; border-style: none solid solid none; border-color: currentColor #009eb8 #009eb8 currentColor; padding: 0cm 5.4pt; width: 5.26%; height: 17pt;"> <p class="MsoNormal">1</p> </td> <td style="border-width: medium 1pt 1pt medium; border-style: none solid solid none; border-color: currentColor #009eb8 #009eb8 currentColor; padding: 0cm 5.4pt; width: 25%; height: 17pt;"> </td> <td style="border-width: medium 1pt 1pt medium; border-style: none solid solid none; border-color: currentColor #009eb8 #009eb8 currentColor; padding: 0cm 5.4pt; width: 19.48%; height: 17pt;"> <p class="MsoNormal">10Ω/±1%, Resistor</p> </td> <td style="border-width: medium 1pt 1pt medium; border-style: none solid solid none; border-color: currentColor #009eb8 #009eb8 currentColor; padding: 0cm 5.4pt; width: 15.28%; height: 17pt;"> <p class="MsoNormal">0603</p> </td> <td style="border-width: medium 1pt 1pt medium; border-style: none solid solid none; border-color: currentColor #009eb8 #009eb8 currentColor; padding: 0cm 5.4pt; width: 14.18%; height: 17pt;"> </td> </tr> <tr style="height: 17pt;"> <td style="border-width: medium 1pt 1pt; border-style: none solid solid; border-color: currentColor #009eb8 #009eb8; padding: 0cm 5.4pt; width: 20.8%; height: 17pt;"> <p class="MsoNormal">R2, R3, R4, R5, R6, </p> <p class="MsoNormal">R7, R8, R9, R11, R12</p> </td> <td style="border-width: medium 1pt 1pt medium; border-style: none solid solid none; border-color: currentColor #009eb8 #009eb8 currentColor; padding: 0cm 5.4pt; width: 5.26%; height: 17pt;"> <p class="MsoNormal">10</p> </td> <td style="border-width: medium 1pt 1pt medium; border-style: none solid solid none; border-color: currentColor #009eb8 #009eb8 currentColor; padding: 0cm 5.4pt; width: 25%; height: 17pt;"> </td> <td style="border-width: medium 1pt 1pt medium; border-style: none solid solid none; border-color: currentColor #009eb8 #009eb8 currentColor; padding: 0cm 5.4pt; width: 19.48%; height: 17pt;"> <p class="MsoNormal">0Ω, Resistor</p> </td> <td style="border-width: medium 1pt 1pt medium; border-style: none solid solid none; border-color: currentColor #009eb8 #009eb8 currentColor; padding: 0cm 5.4pt; width: 15.28%; height: 17pt;"> <p class="MsoNormal">0603</p> </td> <td style="border-width: medium 1pt 1pt medium; border-style: none solid solid none; border-color: currentColor #009eb8 #009eb8 currentColor; padding: 0cm 5.4pt; width: 14.18%; height: 17pt;"> </td> </tr> <tr style="height: 17pt;"> <td style="border-width: medium 1pt 1pt; border-style: none solid solid; border-color: currentColor #009eb8 #009eb8; padding: 0cm 5.4pt; width: 20.8%; height: 17pt;"> <p class="MsoNormal">COUT1, CIN1, </p> <p class="MsoNormal">CIN2, COUT5, </p> <p class="MsoNormal">C2, C3, C4, C5, C6, L2, R14, R15</p> </td> <td style="border-width: medium 1pt 1pt medium; border-style: none solid solid none; border-color: currentColor #009eb8 #009eb8 currentColor; padding: 0cm 5.4pt; width: 5.26%; height: 17pt;"> <p class="MsoNormal">0</p> </td> <td style="border-width: medium 1pt 1pt medium; border-style: none solid solid none; border-color: currentColor #009eb8 #009eb8 currentColor; padding: 0cm 5.4pt; width: 25%; height: 17pt;"> </td> <td style="border-width: medium 1pt 1pt medium; border-style: none solid solid none; border-color: currentColor #009eb8 #009eb8 currentColor; padding: 0cm 5.4pt; width: 19.48%; height: 17pt;"> <p class="MsoNormal">Not Installed</p> </td> <td style="border-width: medium 1pt 1pt medium; border-style: none solid solid none; border-color: currentColor #009eb8 #009eb8 currentColor; padding: 0cm 5.4pt; width: 15.28%; height: 17pt;"> </td> <td style="border-width: medium 1pt 1pt medium; border-style: none solid solid none; border-color: currentColor #009eb8 #009eb8 currentColor; padding: 0cm 5.4pt; width: 14.18%; height: 17pt;"> </td> </tr> <tr style="height: 17pt;"> <td style="border-width: medium 1pt 1pt; border-style: none solid solid; border-color: currentColor #009eb8 #009eb8; padding: 0cm 5.4pt; width: 20.8%; height: 17pt;"> <p class="MsoNormal">J1</p> </td> <td style="border-width: medium 1pt 1pt medium; border-style: none solid solid none; border-color: currentColor #009eb8 #009eb8 currentColor; padding: 0cm 5.4pt; width: 5.26%; height: 17pt;"> <p class="MsoNormal">1</p> </td> <td style="border-width: medium 1pt 1pt medium; border-style: none solid solid none; border-color: currentColor #009eb8 #009eb8 currentColor; padding: 0cm 5.4pt; width: 25%; height: 17pt;"> </td> <td style="border-width: medium 1pt 1pt medium; border-style: none solid solid none; border-color: currentColor #009eb8 #009eb8 currentColor; padding: 0cm 5.4pt; width: 19.48%; height: 17pt;"> <p class="MsoNormal">4 x 2 Pin Header</p> </td> <td style="border-width: medium 1pt 1pt medium; border-style: none solid solid none; border-color: currentColor #009eb8 #009eb8 currentColor; padding: 0cm 5.4pt; width: 15.28%; height: 17pt;"> </td> <td style="border-width: medium 1pt 1pt medium; border-style: none solid solid none; border-color: currentColor #009eb8 #009eb8 currentColor; padding: 0cm 5.4pt; width: 14.18%; height: 17pt;"> </td> </tr> <tr style="height: 17pt;"> <td style="border-width: medium 1pt 1pt; border-style: none solid solid; border-color: currentColor #009eb8 #009eb8; padding: 0cm 5.4pt; width: 20.8%; height: 17pt;"> <p class="MsoNormal">J2, J5</p> </td> <td style="border-width: medium 1pt 1pt medium; border-style: none solid solid none; border-color: currentColor #009eb8 #009eb8 currentColor; padding: 0cm 5.4pt; width: 5.26%; height: 17pt;"> <p class="MsoNormal">2</p> </td> <td style="border-width: medium 1pt 1pt medium; border-style: none solid solid none; border-color: currentColor #009eb8 #009eb8 currentColor; padding: 0cm 5.4pt; width: 25%; height: 17pt;"> </td> <td style="border-width: medium 1pt 1pt medium; border-style: none solid solid none; border-color: currentColor #009eb8 #009eb8 currentColor; padding: 0cm 5.4pt; width: 19.48%; height: 17pt;"> <p class="MsoNormal">3- Pin Header</p> </td> <td style="border-width: medium 1pt 1pt medium; border-style: none solid solid none; border-color: currentColor #009eb8 #009eb8 currentColor; padding: 0cm 5.4pt; width: 15.28%; height: 17pt;"> </td> <td style="border-width: medium 1pt 1pt medium; border-style: none solid solid none; border-color: currentColor #009eb8 #009eb8 currentColor; padding: 0cm 5.4pt; width: 14.18%; height: 17pt;"> </td> </tr> <tr style="height: 1cm;"> <td style="border-width: medium 1pt 1pt; border-style: none solid solid; border-color: currentColor #009eb8 #009eb8; padding: 0cm 5.4pt; width: 20.8%; height: 1cm;"> <p class="MsoNormal">TP1, TP2, TP3, Z3, </p> <p class="MsoNormal">Z5, Z7, Z8</p> </td> <td style="border-width: medium 1pt 1pt medium; border-style: none solid solid none; border-color: currentColor #009eb8 #009eb8 currentColor; padding: 0cm 5.4pt; width: 5.26%; height: 1cm;"> <p class="MsoNormal">7</p> </td> <td style="border-width: medium 1pt 1pt medium; border-style: none solid solid none; border-color: currentColor #009eb8 #009eb8 currentColor; padding: 0cm 5.4pt; width: 25%; height: 1cm;"> <p class="MsoNormal">PWM, EN, LX, SDA, </p> <p class="MsoNormal">SCL, VCP, VIN_1</p> </td> <td style="border-width: medium 1pt 1pt medium; border-style: none solid solid none; border-color: currentColor #009eb8 #009eb8 currentColor; padding: 0cm 5.4pt; width: 19.48%; height: 1cm; white-space: nowrap;"> <p class="MsoNormal">Test Pin</p> </td> <td style="border-width: medium 1pt 1pt medium; border-style: none solid solid none; border-color: currentColor #009eb8 #009eb8 currentColor; padding: 0cm 5.4pt; width: 15.28%; height: 1cm;"> </td> <td style="border-width: medium 1pt 1pt medium; border-style: none solid solid none; border-color: currentColor #009eb8 #009eb8 currentColor; padding: 0cm 5.4pt; width: 14.18%; height: 1cm;"> </td> </tr> <tr style="height: 51pt;"> <td style="border-width: medium 1pt 1pt; border-style: none solid solid; border-color: currentColor #009eb8 #009eb8; padding: 0cm 5.4pt; width: 20.8%; height: 51pt;"> <p class="MsoNormal">GP1, GP2, GP3, GP4, GP5, GP6, GP7, GP8, GP9, GP10, GP11, GP12</p> </td> <td style="border-width: medium 1pt 1pt medium; border-style: none solid solid none; border-color: currentColor #009eb8 #009eb8 currentColor; padding: 0cm 5.4pt; width: 5.26%; height: 51pt;"> <p class="MsoNormal">12</p> </td> <td style="border-width: medium 1pt 1pt medium; border-style: none solid solid none; border-color: currentColor #009eb8 #009eb8 currentColor; padding: 0cm 5.4pt; width: 25%; height: 51pt;"> <p class="MsoNormal">VOUT, VIN, GND, LED1, LED2, LED3, LED4, LED5, LED6</p> </td> <td style="border-width: medium 1pt 1pt medium; border-style: none solid solid none; border-color: currentColor #009eb8 #009eb8 currentColor; padding: 0cm 5.4pt; width: 19.48%; height: 51pt; white-space: nowrap;"> <p class="MsoNormal">Golden Pin</p> </td> <td style="border-width: medium 1pt 1pt medium; border-style: none solid solid none; border-color: currentColor #009eb8 #009eb8 currentColor; padding: 0cm 5.4pt; width: 15.28%; height: 51pt;"> </td> <td style="border-width: medium 1pt 1pt medium; border-style: none solid solid none; border-color: currentColor #009eb8 #009eb8 currentColor; padding: 0cm 5.4pt; width: 14.18%; height: 51pt;"> </td> </tr> </tbody> </table> <p class="MsoNormal"> </p>

8. EVB Layout

<p class="23CxSpFirst"><a href="/content/dam/richtek-eds/resources/evaluation-boards/evb_rt8555wsc/html-images/image003_en.jpg" class="fancybox"><img width="491" height="352" width="491" height="352" id="圖片 1" style="border-width: 0px; border-style: solid;" alt="Technical Document Image Preview" src="/content/dam/richtek-eds/resources/evaluation-boards/evb_rt8555wsc/html-images/image003_en.jpg" /></a></p> <p class="23CxSpLast">Top View (1^st layer)</p> <p class="MsoNormal"><a href="/content/dam/richtek-eds/resources/evaluation-boards/evb_rt8555wsc/html-images/image004_en.jpg" class="fancybox"><img width="491" height="351" width="491" height="351" id="圖片 4" style="border-width: 0px; border-style: solid;" alt="Technical Document Image Preview" src="/content/dam/richtek-eds/resources/evaluation-boards/evb_rt8555wsc/html-images/image004_en.jpg" /></a></p> <p class="3">PCB Layout—Inner Side (2^nd Layer)</p> <p class="MsoNormal"><a href="/content/dam/richtek-eds/resources/evaluation-boards/evb_rt8555wsc/html-images/image005_en.jpg" class="fancybox"><img width="492" height="352" width="492" height="352" id="圖片 7" style="border-width: 0px; border-style: solid;" alt="Technical Document Image Preview" src="/content/dam/richtek-eds/resources/evaluation-boards/evb_rt8555wsc/html-images/image005_en.jpg" /></a></p> <p class="3">PCB Layout—Inner Side (3^rd Layer)</p> <p class="MsoNormal"><a href="/content/dam/richtek-eds/resources/evaluation-boards/evb_rt8555wsc/html-images/image006_en.jpg" class="fancybox"><img width="492" height="353" width="492" height="353" id="圖片 3" style="border-width: 0px; border-style: solid;" alt="Technical Document Image Preview" src="/content/dam/richtek-eds/resources/evaluation-boards/evb_rt8555wsc/html-images/image006_en.jpg" /></a></p> <p class="23">Bottom View (4^th Layer)</p>