GL852GX is Genesys Logic’s premium 4-port hub solution which fully complies with Universal Serial Bus Specification Revision 2.0. GL852GX implements multiple TT* (Note1) architecture that provide dedicated TT* to each downstream (DS) ports, which guarantee Full-Speed(FS) data passing bandwidth when multiple FS device perform heavy loading operations. The controller inherits Genesys Logic’s cutting edge technology on cost and power efficient serial interface design. GL852GX has proven compatibility, lower power consumption figure and better cost structure above all USB2.0 hub solutions worldwide.
GL852GX implements multiple hub configuration features onto internal mask ROM, which traditionally requires one external EEPROM. The microprocessor detects general purpose I/O (GPIO) status during the initial stage to configure hub settings such as (1) number of DSport, (2) declare of compound device (3) gang/individual mode selection…etc. External EEPROM can be removed if no vendor specified PID/VID or product string is required for the application. Besides, GL852GX can provide two 12MHz clock output, which can dramatically reduce the total BOM cost by saving two crystals on the PCBA. This feature is especially suitable for multi-chip applications such as docking.
GL852GX supports two package types, summarized as below table. LQFP48 package provides full hub features such as (1) two-color (green/amber) status LEDs for each DS ports, (2) Individual/Gang mode power management scheme that indicates DS port over-current events. (3) Number of DS ports setting configured by GPIO setting (4) non-removable declaration configured by GPIO setting (5) Support both 93C46 and 24C02 EEPROM (6) power switch polarity selections (7) 12MHz clock output…etc. QFN28 package support only partial hub features but provide smaller footprint (5x5mm) that targets space limited PCB layout environments such as embedded system or UMPC/MID applications.
● Compliant to USB Specification Revision 2.0
− 4 downstream ports
− Upstream port supports both high-speed (HS) and full-speed (FS) traffic
− Downstream ports support HS, FS, and low-speed (LS) traffic
− 1 control pipe (endpoint 0, 64-byte data payload) and 1 interrupt pipe (endpoint 1, 1-byte data payload)
− Backward compatible to USB specification Revision 1.1
● On-chip 8-bit micro-processor
− RISC-like architecture
− USB optimized instruction set
− Dual cycle instruction execution
− Performance: 6 MIPS @ 12MHz
− With 64-byte RAM and 2K internal ROM
− Support customized PID, VID by reading external EEPROM
− Support downstream port configuration by reading external EEPROM
● Multiple Transaction translator (MTT)
− MTT provides respective TT control logics for each downstream port
● Each downstream port supports two-color status indicator, with automatic and manual modes
compliant to USB specification Revision 2.0
● Built-in upstream port 1.5KΩ pull-up and downstream port 15KΩ pull-down resistors
● Support both individual and gang modes of power management and over-current detection
for downstream ports (For LQFP48 only, individual mode not available on QFN28 package)
● Conform to bus power requirements of USB 2.0 specification
● Automatic switching between self-powered and bus-powered modes
● Integrate USB 2.0 transceiver
● Embedded PLL support external 12 MHz crystal / Oscillator clock input
● Support 12MHz clock output (LQFP48 x2, QFN28 x1)
● Support compound-device (non-removable in downstream ports) by I/O pin configuration
(Not available on QFN 28 package)
● Number of Downstream port can be configured by GPIO without external EEPROM
(Not available on QFN 28 package)
● Operate on 3.3 Volts (Built-in 3.3V to 1.8V regulator)
● Improve output drivers with slew-rate control for EMI reduction
● Internal power-fail detection for ESD recovery
● Available package type: 48-pin LQFP and 28-pin QFN
● Applications:
− Stand-alone USB hub / USB Docking
− UMPC/MID, motherboard on-board applications
− Consumer electronics built-in hub application
− Monitor built-in hub
− Embedded systems
− Compound device to support USB hub function such as keyboard hub applications
