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TUSB2036

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SLLS372H – MARCH 2000 – REVISED JANUARY 2016

Product Folder Links: TUSB2036

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5 Description (Continued)

The EXTMEM (pin 26) enables or disables the optional EEPROM interface. When EXTMEM is high, the vendor

and product IDs (VID and PID) use defaults, such that the message displayed during enumeration is General

Purpose USB Hub.

The TUSB2036 supports both bus-powered and self-powered modes. External power-management devices,

such as the TPS2044, are required to control the 5-V power source switching (on/off) to the downstream ports

and to detect an overcurrent condition from the downstream ports individually or ganged.

An individually port power controlled hub switches power on or off to each downstream port as requested by the

USB host. Also when an individually port power controlled hub senses an over-current event, only power to the

affected downstream port will be switched off. A ganged hub switches on power to all its downstream ports when

power is required to be on for any port. The power to the downstream ports is not switched off unless all ports

are in a state that allows power to be removed. Also when a ganged hub senses an over-current event, power to

all downstream ports will be switched off.

The logic level of the MODE pin controls the selection of a crystal input to drive an internal oscillator or an

external clock source.