4-Port USB 2.0 Hub Controller

Datasheet

Chapter 8 Implementation Notes

The following sections consist of select functional explanations to aid in implementing the Hub Controller into a system.

8.1Configuration Implementations

The USB20H04 is normally configured by an external EEPROM connected directly to the serial interface. Typical circuit diagrams are shown below. For a more detailed discussion of the serial interface, including how to configure the USB20H04 using the SMBus mode, please see Application Note 9.29, "USB20H04 4- Port USB 2.0 Hub Controller, Configuration Programming". The Application Note also discusses designing a Hub system that supports In Circuit Programming of the EEPROM.

8.1.1Interfacing a 2-wire Serial EEPROM

The I2C EEPROM interface is designed to attach to a single “dedicated” I2C EEPROM. It conforms to the Standard-mode I2C Specification (100kbit/s transfer rate and 7-bit addressing) for protocol and electrical compatibility. The circuit board designer is required to place external pull-up resistors (10K ohm recommended) on the SDA & SCL lines (per SMBus 1.0 Specification, and EEPROM manufacturer guidelines) to VDD in order to assure proper operation.

Figure 8.1 - 2-Wire EEPROM Interface

Revision 1.63 (03-30-07)

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SMSC USB20H04

DATASHEET