Hardware Set Up; Configuration Switches - Texas Instruments TUSB8040AEVM User Manual

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Configuration Switches

The TI TUSB8040AEVM has two sets of switches to facilitate configuration changes. Changing these
switch settings without a complete understanding of the result is not recommended. Configuration inputs
are only read by the TUSB8040A during power on reset, changing the switch settings while the EVM is
powered on will have no effect. Please refer to the EVM schematic for additional information (included in
the appendix).
The switch definitions are as follows, with the standard setting in parenthesis:
SW1_1 (on): FULLPWRz Switch. The TUSB8040A has an internal pull up on this terminal, so the
TUSB8040A defaults to a non full power management mode. If the switch is set to the ON position, the
terminal is pulled low and full power management mode is enabled. This means that the TUSB8040A
reports that it supports downstream port power switching in the USB descriptors it sends to the USB host.
Since the TUSB8040AEVM does implement downstream port power switching, full power management
mode should be enabled.
SW1_2 (off): SMBUSz Switch. The TUSB8040A has an internal pull up on this terminal, so I
mode is enabled by default. If the switch is set to the ON position, the terminal is pulled low and SMBUS
mode is enabled.
SLLU163 – May 2012
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Figure 2. Configuration Switches
Copyright © 2012, Texas Instruments Incorporated
SLLU163 – May 2012

Hardware Set Up

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C interface
Hardware Set Up
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