RT6206AHGQW Evaluation Board your power partner. 5.5A, 18V, 650kHz, ACOT™ Synchronous Step-Down Converter Purpose The RT6206AH is a synchronous step-down DC/DC converter with Advanced Constant On-Time (ACOT™) mode control. This document explains the function and use of the RT6206AH evaluation board (EVB), and provides information to enable operation, modification of the evaluation board and circuit to suit individual requirements. Table of Contents Purpose ................................................................................................................................................................. 1 Introduction............................................................................................................................................................ 2 Key Performance Summary Table .......................................................................................................................... 2 Bench Test Setup Conditions ................................................................................................................................. 3 Schematic, Bill of Materials & Board Layout ........................................................................................................... 5 More Information.................................................................................................................................................... 8 Important Notice for Richtek Evaluation Board ....................................................................................................... 8 EVB_RT6206AHGQW-00 March 2016 1 http://www.richtek.com RT6206AHGQW Evaluation Board your power partner. Introduction General Product Information The RT6206AH is a synchronous step-down DC/DC converter with Advanced Constant On-Time (ACOT™) mode control. It achieves high power density to deliver up to 5.5A output current from a 4.5V to 18V input supply. The proprietary ACOT™ mode offers an optimal transient response over a wide range of loads and all kinds of ceramic capacitors, which allows the device to adopt very low ESR output capacitor for ensuring performance stabilization. In addition, RT6206AH keeps an excellent constant switching frequency under line and load variation and the integrated synchronous power switches with the ACOT™ mode operation provides high efficiency in whole output current load range. Cycle-by-cycle current limit provides an accurate protection by a valley detection of low side MOSFET and external soft-start setting eliminates input current surge during startup. Protection functions include thermal shutdown for RT6206AH. Product Feature ACOT™ Mode Enables Fast Transient Response 4.5V to 18V Input Voltage Range 5.5A Output Current 35mΩ Internal Low Side N-MOSFET Advanced Constant On-Time Control Support All Ceramic Capacitors Up to 95% Efficiency Adjustable Output Voltage from 0.765V to 7V Adjustable Soft-Start Cycle-by-Cycle Current Limit Input Under-Voltage Lockout Thermal Shutdown Key Performance Summary Table Key Features Evaluation Board Number : PCB066_V1 Input Voltage Range 4.5V to 18V Max Output Current 5.5A Default Output Voltage 1.05V Default Marking & Package Type RT6206AHGQW, WDFN-10L 3x3 Operation Frequency Fixed 650kHz EVB_RT6206AHGQW-00 March 2016 2 http://www.richtek.com RT6206AHGQW Evaluation Board your power partner. Bench Test Setup Conditions Headers Description and Placement 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 [email protected]. Test Points The EVB is provided with the test points and pin names listed in the table below. Test point/ Pin name Signal Comment (expected waveforms or voltage levels on test points) VIN Input voltage Power input. EN Enable test point Externally pulled high to enable and pulled low to disable this chip. It is internally pulled up to high when the pin is floating. GND Ground The exposed pad must be soldered to a large PCB and connected to GND for maximum power dissipation. VREG5 Internal Regulator Output Internal Regulator Output. Connect a 1µF capacitor to GND to stabilize output voltage. SS Soft-Start Control. Connect an external capacitor between this pin and GND to set the soft-start time. PG Power good test point Output of power good indicator. BOOT Bootstrap supply test point Bootstrap supply for high-side gate driver. Connect a capacitor between the BOOT and SW pins. SW Switch node test point Connect this pin to an external L-C filter. EVB_RT6206AHGQW-00 March 2016 3 http://www.richtek.com RT6206AHGQW Evaluation Board your power partner. Power-up & Measurement Procedure 1. Apply a 12V nominal input power supply (4.5 < VIN < 18V) to the VIN and GND terminals. 2. Set the jumper at JP1to connect terminals 2 and 3, connecting EN to enable operation. 3. Verify the output voltage (approximately 1.05V) between VOUT and GND. 4. Connect an external load up to 5.5A to the VOUT and GND terminals and verify the output voltage and current. Output Voltage Setting Set the output voltage with the resistive divider (R2, R3) between VOUT and GND with the midpoint connected to FB. The output is set by the following formula : VOUT = 0.765 × (1 + EVB_RT6206AHGQW-00 R2 ) R3 March 2016 4 http://www.richtek.com RT6206AHGQW Evaluation Board your power partner. Schematic, Bill of Materials & Board Layout EVB Schematic Diagram Bill of Materials Reference Qty Part Number Description Package Manufacture U1 1 RT6206AHGQW DC/DC Converter WDFN-10L 3x3 RICHTEK C1, C3 2 GRM31CR71E106KA12L 10µF/25V/X7R C-1206 MURATA C4, C10, C7 3 C1608X7R1H104KT000N 0.1µF/50V/X7R C-0603 TDK C8, C9 2 GRM31CR61A226KE19L 22µF/10V/X5R C-1206 MURATA C6 1 0603B332K500 3.3nF/50V/X7R C-0603 WALSIN C5 1 C2012X7R1E105KT 1µF/25V/X7R C-0805 TDK C2 1 L1 1 1.4µH/7A 8 x 8 x 4 mm TAIYO YUDEN R2 1 8.25k R-0603 R3 1 22.1k R-0603 R1, R4 2 100k R-0603 EVB_RT6206AHGQW-00 March 2016 NC NR8040T1R4N 5 http://www.richtek.com RT6206AHGQW Evaluation Board your power partner. PCB Layout Top View (1st layer) PCB Layout—Inner Side (2nd Layer) EVB_RT6206AHGQW-00 March 2016 6 http://www.richtek.com RT6206AHGQW Evaluation Board your power partner. PCB Layout—Inner Side (3rd Layer) Bottom View (4th Layer) EVB_RT6206AHGQW-00 March 2016 7 http://www.richtek.com RT6206AHGQW Evaluation Board your power partner. More Information For more information, please find the related datasheet or application notes from Richtek website http://www.richtek.com. Important Notice for Richtek Evaluation Board THIS DOCUMENT IS FOR REFERENCE ONLY, NOTHING CONTAINED IN THIS DOCUMENT SHALL BE CONSTRUED AS RICHTEK’S WARRANTY, EXPRESS OR IMPLIED, UNDER CONTRACT, TORT OR STATUTORY, WITH RESPECT TO THE PRESENTATION HEREIN. IN NO EVENT SHALL RICHTEK BE LIABLE T O BUYER OR USER FOR ANY AND ALL DAMAGES INCLUDING WITHOUT LIMITATION TO DIRECT, INDIRECT, SPECIAL, PUNITIVE OR CONSEQUENTIAL DAMAGES. EVB_RT6206AHGQW-00 March 2016 8 http://www.richtek.com