Microchip Technology EVB-USB5744, Руководство пользователя

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EVB-USB5744 Evaluation Board User’s Guide
DS50002306B-page 14
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2015 Microchip Technology Inc.
The table below describes the port enable/disable strap options available for all four
ports on the USB5744.
2.2 POWER SOURCE - SELF-POWERED
The EVB-USB5744 only supports self-powered operation, and is powered through one +12.0 V
regulated 'wall wart' external power supply. The power supply plugs into the 2.5 mm connector
J9 on the board. Alternatively, an external voltage can be injected onto the J6
Ext. 12 V header,
which is not populated by default. The +12.0 V feeds a 6 A regulator which o5.25 V
across the board. This +5.25 V output supplies the +3.3 V and +1.2 V onboard regulators.
2.3 DOWNSTREAM PORT POWER CONTROL
USB power to the four downstream ports are controlled via port power controllers with
auto-discharge function. This provides up to 2.1 A of USB battery charging power to
each port, limited to a total of 5 A at any one time.
FIGURE 2-4: INITIAL CONFIGURATION
TABLE 2-3: PORT ENABLE/DISABLE STRAP OPTIONS
Downstream
Port
Associated
Switch
Switch Position LED
1 SW1 1-2, 4-5 = Port Enabled (Default)
2-3, 5-6 = Port Disabled
2 SW2 1-2, 4-5 = Port Enabled (Default)
2-3, 5-6 = Port Disabled
3 SW3 1-2, 4-5 = Port Enabled (Default)
2-3, 5-6 = Port Disabled
4 SW4 1-2, 4-5 = Port Enabled (Default)
2-3, 5-6 = Port Disabled