原标题：Microchip USB5734USB 3.0集线器解决方案

　　microchip公司的USB5734是低功耗OEM可配置的USB 3.0多端口转发器控制器,具有四个下行端口和嵌入USB应用的先进特性,完全和USB 3.0标准以及USB 2.0链路电源管理附录兼容,支持5 Gbps超速(SS), 480Mbps高速(HS),12Mbps全速(FS)和1.5Mbps低速(LS)下行设备,支持包括YD/T 1591-2009在内的多种充电标准,主要用在USB集线器,平板电脑坞站,PC主板,PC监视器坞站和多功能USB 3.0外设.本文介绍了USB5734产品亮点和主要优势,框图,以及USB3.0集线器评估板EVB-USB5744主要特性,电路图,材料清单和PCB元件布局图.

　　The Microchip USB5734 hub is low-power, OEM configurable, USB 3.0 hub feature controller with 4 downstream portsand advanced features for embedded USB applications. The USB5734 is fully compliant with the USB 3.0 Specificationand USB 2.0 Link Power Management Addendum. The USB5734 supports 5 Gbps SuperSpeed (SS), 480 Mbps Hi-Speed (HS), 12 Mbps Full-Speed (FS), and 1.5 Mbps Low-Speed (LS) USB downstream devices on all enabled downstreamports.

　　The USB5734 supports the legacy USB speeds (HS/FS/LS) through a dedicated USB 2.0 hub feature controller that isthe culmination of five generations of Microchip hub feature controller design and experience with proven reliability,interoperability, and device compatibility. The SuperSpeed hub feature controller operates in parallel with the USB 2.0controller, decoupling the 5 Gbps SS data transfers from bottlenecks due to the slower USB 2.0 traffic.

　　The USB5734 enables OEMs to configure their system using “Configuration Straps.” These straps simplify the configurationprocess assigning default values to USB3.0 ports and GPIOs OEMs can disable ports, enable battery chargingand define GPIO functions as default assignments on power up removing the need for OTP or external SPI ROM.

　　The USB5734 supports both upstream battery charger detection and downstream battery charging. The USB5734 integratedbattery charger detection circuitry supports the USB-IF Battery Charging (BC1.2) detection method and mostApple devices. The USB5734 provides the battery charging handshake and supports the following USB-IF

　　BC1.2charging profiles:

　　• DCP: Dedicated Charging Port (Power brick with no data)

　　• CDP: Charging Downstream Port (1.5A with data)

　　• SDP: Standard Downstream Port (0.5A with data)

　　• Custom profiles loaded via SMBus or OTP

　　The USB5734 provides an additional USB endpoint dedicated for use as a USB to I2C/UART/SPI/GPIO interface, allowingexternal circuits or devices to be monitored, controlled, or configured via the USB interface. Additionally, theUSB5734 includes many powerful and unique features such as:FlexConnect, which provides flexible connectivity options. One of the USB5734’s downstream ports can be reconfiguredto become the upstream port, allowing master capable devices to control other devices on the hub.PortSwap, which adds per-port programmability to USB differential-pair pin locations.PortSwap allows direct alignmentof USB signals (D+/D-) to connectors to avoid uneven trace length or crossing of the USB differential signals on thePCB.

　　PHYBoost, which provides programmable levels of Hi-Speed USB signal drive strengthin the downstream port transceivers. PHYBoost attempts to restore USB signal integrityin a compromised system environment. The graphic on the right shows an example ofHi-Speed USB eye diagrams before and after PHYBoost signal integrity restoration. Ina compromised system environmentVariSense, which controls the USB receiver sensitivity enabling programmable levels of USB signal receive sensitivity.

　　This capability allows operation in a sub-optimal system environment, such as when a captive USB cable is used.The USB5734 can be configured for operation through internal default settings. Custom OEM configurations are supportedthrough external SPI ROM or OTP ROM. All port control signal pins are under firmware control in order to allowfor maximum operational flexibility, and are available as GPIOs for customer specific use.

　　The USB5734 is available in commercial (0℃ to +70℃) and industrial (-40℃ to +85℃) temperature ranges

　　USB5734亮点:

　　• USB Hub Feature Controller IC with 4 USB 3.0/2.0downstream ports

　　• USB-IF Battery Charger revision 1.2 support onup & downstream ports (DCP, CDP,SDP)

　　• FlexConnect: Downstream port able to swap withupstream port, allowing master capable devicesto control other devices on the hub

　　• USB to I2C/UART/SPI/GPIO bridge endpoint support

　　• USB Link Power Management (LPM) support

　　• Enhanced OEM configuration options availablethrough either OTP or SPI ROM

　　• Available in 64-pin (9 x 9 mm) SQFN lead-free,RoHS compliant package

　　• Commercial and industrial grade temperaturesupport

　　• Configuration Straps: Predefined configuration ofsystem level functions including GPIOs

　　USB5734主要优势:

　　• USB 3.0 compliant 5 Gbps, 480 Mbps, 12 Mbpsand 1.5 Mbps operation

　　- 5 V tolerant USB 2.0 pins

　　- 1.32 V tolerant USB 3.0 pins

　　- Integrated termination & pull-up/pull-down resistors

　　• Supports per port battery charging of most popularbattery powered devices

　　- USB-IF Battery Charging rev. 1.2 support(DCP, CDP, SDP)

　　- Apple portable product charger emulation

　　- Chinese YD/T 1591-2006 charger emulation

　　- Chinese YD/T 1591-2009 charger emulation

　　- European Union universal mobile charger support

　　- Support for Microchip USC100x family of batterycharging controllers

　　- Supports additional portable devices

　　• Smart port controller operation

　　- Firmware handling of companion port controllers

　　• On-chip microcontroller

　　- Manages I/Os, VBUS, and other signals

　　• 8 KB RAM, 64 KB ROM

　　• 8 KB One Time Programmable (OTP) ROM

　　- Includes on-chip charge pump

　　• Configuration programming via OTP ROM, SPIROM, or SMBus

　　• PortSwap

　　- Configurable differential intro-pair signal swapping

　　• PHYBoostTM

　　- Programmable USB transceiver drive strength forrecovering signal integrity

　　• VariSenseTM

　　- Programmable USB receiver sensitivity

　　• Compatible with Microsoft Windows 8, 7, XP,Apple OS X 10.4+, and Linux hub drivers

　　• Optimized for low-power operation andlow thermal dissipation

　　• Package

　　- 64-pin SQFN (9 x 9 mm)

　　• Environmental

　　- 3 kV HBM JESD22-A114F ESD protection

　　- Commercial temperature range (0℃ to +70℃)

　　- Industrial temperature range (-40℃ to +85℃)

　　USB5734目标应用:

　　• Standalone USB Hubs

　　• Laptop Docks

　　• PC Motherboards

　　• PC Monitor Docks

　　• Multi-function USB 3.0 Peripherals

　　图1. USB5734内部框图

　　评估板EVB-USB5744 USB3.0集线器

　　The EVB-USB5744 is a demonstration and evaluation platform that provides the necessary requirements and interface options for evaluating the USB5744 Smart Hub on a 4-layer RoHS-compliant Printed Circuit Board (PCB). This will allow the user to gain an understanding of the product and accelerate the integration of the EVB-USB5744 into the user’s design. The EVB-USB5744 is compliant with the USB 3.0 USB Specification and supports Super-Speed (SS), High-Speed (HS), Full-Speed (FS), and Low-Speed (LS) USB signaling for complete coverage of all defined USB operation speeds. The evaluation platform supports four downstream ports that are USB 2.0 and USB 3.0 compliant. The EVB-USB5734 is also designed for flexible configuration solutions. It can be configured via default internal register settings, downloadable external firmware to an on-board SPI Flash, through SMBus, or through the on-board configuration switches.

　　The EVB-USB5734 allows the user to evaluate the four port, SuperSpeed USB5734 Smart hub with I/O Bridging and FlexConnect. This evaluation board includes an onboard SPI interface as well as strap options for Port Disable, Port Battery Charging Disable, Non-Removeable Port Select and preset application configurations for GPIOs. The kit includes five I/O daughter cards for evaluating the different GPIO configuration options available on the USB5734.

　　评估板EVB-USB5744主要特性:

　　USB5744 in a 56-pin QFN RoHS compliant package

　　USB 3.0 compliant (SS, HS, FS, and LS operation)

　　USB pins are 5 V tolerant

　　Self powered operation

　　Four downstream USB 2.0/3.0 ports

　　All downstream ports support individual port power and overcurrent sense

　　All downstream ports are battery charge enabled (2.1A max per port)

　　Can support up to 5A down stream Port Power at any one time

　　Onboard SPI Flash for external downloadable firmware

　　Low-cost 4-layer space saving design

　　Operates from a single voltage (+12.0 V, regulated) external power supply

　　Onboard 25 MHz crystal or external clock input

　　Single onboard +5.25 V, 6 Amp regulator

　　Single onboard +3.3 V, 0.5 Amp regulator

　　Single onboard +1.2 V, 1 Amp regulator

　　Port Power and Port Enable LED indicators

　　LED indicators for SPI/Strap Configuration

　　图2.评估板EVB-USB5744外形图

　　图3.评估板EVB-USB5744电路图(1)

　　评估板EVB-USB5744材料清单: