loading
Richtek

RT6280BHGQUF Step-Down Converter Evaluation Board

EVB_RT6280BHGQUF

Share

The RT6280B is an advanced constant on-time (ACOT) mode synchronous buck converter. The main control loop of the RT6280B using an advanced constant on-time (ACOT) mode control which provides a very fast transient response. The RT6280B operates from 4.5V to 23V input voltage, the output voltage can be programmed between 0.6V to 5.1V.

Purpose

The RT6280B is an advanced constant on-time (ACOT) mode synchronous buck converter with the input voltage range from 4.5V to 23V and provides 10A output current. This document explains the function and use of the RT6280B evaluation board (EVB), and provides information to enable operation, modification of the evaluation board and circuit to suit individual requirements.


Introduction

General Product Information

The RT6280B is an advanced constant on-time (ACOT) mode synchronous buck converter. The main control loop of the RT6280B using an advanced constant on-time (ACOT) mode control which provides a very fast transient response. The RT6280B operates from 4.5V to 23V input voltage, the output voltage can be programmed between 0.6V to 5.1V.


Product Feature

  • Input Voltage Range : 4.5V to 23V
  • 10A Output Current
  • ACOTMode Performs Fast Transient Response
  • ACOTArchitecture to Enable All MLCC Output Capacitor Usage
  • Fixed 500kHz Switching Frequency
  • High Efficient Internal Power MOSFET Switch 20mΩ (High-Side) and 10mΩ (Low-Side)
  • Adjustable Output Voltage from 0.6V to 5.1V
  • Pre-biased Soft-Start
  • Cycle-by-Cycle Over-Current Protection
  • Input Under-Voltage Lockout
  • Thermal Shutdown Protection
  • Output Over/Under-Voltage Protection

  • Key Performance Summary Table

    Key Features

    Evaluation Board Number: PCB091_V1

    Default Input Voltage

    12V

    Max Output Current

    10A

    Default Output Voltage

    3.3V

    Default Marking & Package Type

    RT6280BHGQUF, UQFN-12HL 3x3 (FC)

    Operation Frequency

    Steady 500kHz at all loads



    Bench Test Setup Conditions

    Headers Description and Placement

    Technical Document Image Preview

    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 evb_service@richtek.com.



    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. Support 4.5V to 23V Input Voltage. Must bypass with a suitable large ceramic capacitor at this pin.

    EN

    Enable test point

    Enable control. Pull this pin high to turn on the Buck. Do not leave this pin floating.

    GND

    Ground

    Ground.

    PGOOD

    Power good test point

    Power good Indicator. Open drain output when the output voltage is within 90% to 120% of regulation point.

    FB

    Feedback voltage input

    The pin is used to set the output voltage of the converter to regulate to the desired voltage via a resistive divider. Feedback reference = 0.6V.

    VCC

    Internal regulator output

    5V linear regulator Output for Internal Control Circuit. A capacitor (typical 1µF) should be connected to AGND. Don’t connect to external Load.

    BOOT

    Bootstrap supply test point

    Bootstrap supply for high-side gate driver. Connect a 0.1µF ceramic capacitor between the BOOT and SW pins.

    LX

    Switch node test point

    Connect this pin to an external L-C filter.

    BYP

    Bypass test point

    Bypass input for the internal LDO. BYP is externally connected to the output of switching regulator. When the BYP voltage rises above the bypass switch turn-on threshold, the LDO regulator shuts down and the VCC pin is connected to the BYP pin through an internal switch.

    ILIMT

    Current limit seeting

    Current limit setting pin. The current limit is set to 8A, 10A or 12A when this pin is pull low, floating or pull high respectively.



    Power-up & Measurement Procedure

    1. Connect input power (4.5V < VIN < 23V) and input ground to VIN and GND test pins respectively.

    2. Connect positive end and negative terminals of load to VOUT and GND test pins respectively.

    3. Set the jumper at J7 to connect terminals 2 and 3, connecting EN to VIN through resistor REN, to enable operation.

    4. Verify the output voltage (approximately 3.3V) between VOUT and GND.

    5. Connect an external load up to 10A to the VOUT and GND terminals and verify the output voltage and current.


    Output Voltage Setting

    Set the output voltage with the resistive divider (R4, R5) between VOUT and GND with the midpoint connected to FB. The output is set by the following formula:

    Technical Document Image Preview



    Schematic, Bill of Materials & Board Layout

    EVB Schematic Diagram

    Technical Document Image Preview



    Bill of Materials

    Reference

    Qty

    Part Number

    Description

    Package

    Manufacturer

    U1

    1

    RT6280BHGQUF

    DC-DC Converter

    UQFN-12HL 3x3 (FC)

    RICHTEK

    C3

    1

    C1608X5R0J475KT

    4.7µF/6.3V/0603

    C-0603

    TDK

    C4

    1

    C1608X5R1E105KT000E

    1µF/25V/X5R/0603

    C-0603

    TDK

    C6, C9, C15, C16

    4

    C1608X7R1H104KT000N

    0.1µF/50V/X7R/0603

    C-0603

    TDK

    C7

    1

    0603N680J500

    68pF/50V/NPO/0603

    C-0603

    WALSIN

    C8, C10

    2

    UMK325BJ106MM

    10µF/50V/X5R/1210

    C-1210

    TAIYO YUDEN

    C11, C12

    2

    C3225X5R1E226MT

    22µF/25V/X5R/1210

    C-1210

    TDK

    L1

    1

    7443552150

    1.5µH

    L-GSCDK104

    WE

    R3, R19

    2

    WR06X1003FTL

    100k/0603

    R-0603

    WALSIN

    R4

    1

    RTT039092FTP

    90.9k/0603

    R-0603

    WALSIN

    R5

    1

    WR06X2002FTL

    20k/0603

    R-0603

    WALSIN

    R11

    1

    WR06X3602FTL

    36k/0603

    R-0603

    WALSIN

    R12, R15

    2

    WR06X000PTL

    0R/0603

    R-0603

    WALSIN

    R16

    1

    WR06X7502FTL

    75k/0603

    R-0603

    WALSIN

    R18

    1

    WR06X1002FTL

    10k/0603

    R-0603

    WALSIN



    PCB Layout

    Technical Document Image Preview

    Top View (1st layer)

    Technical Document Image Preview

    PCB Layout—Inner Side (2nd Layer)

    Technical Document Image Preview

    PCB Layout—Inner Side (3rd Layer)

    Technical Document Image Preview

    Bottom View (4th Layer)

    Title Last Update Share Download
    Evaluation Board User Guide 2018/06/04
    Bill of Materials 2018/06/04
    Gerber File 2018/06/04
    Schematic 2018/06/04
    RT6280B

    23V, 10A, 500kHz ACOT®同步Buck轉換器

    RT6280B

    RT6280B是簡單易用的10A同步Buck轉換器,輸入電壓範圍為4.5V~23V,內建0.6V精準參考電壓源,集成了低導通電阻的MOSFET功率開關,轉換效率高,使用晶核倒裝的UQFN-12HL 3x3封裝。RT6280B採用ACOT®控制架構,具有超快瞬態回應速度,週邊元件少,在各種輸入電壓、負載和輸出電壓下都具有基本恒定的工作頻率,採用強制PWM模式以滿足應用對精確輸出電壓調整特性的需求。它對上下橋的電流都進行檢測,具備強大的保護特性,使用逐週期電流限制方式應對輸出短路、過流和電感飽和等嚴峻情形,並有內建的軟起動設計避免啟動過程可能導致的電流衝擊,還具有輸入欠壓鎖定保護、輸出欠壓保護、輸出過壓保護和溫度過高保護等特性,確保在任何情形下都可安全、平穩地運行。

    TOP