EVB-USB2517 Evaluation Board User Manual (Revision A)

SMSC EVB-USB2517 Revision A

3

Revision 1.2 (1-7-09)

USER MANUAL

2 Hardware Configuration

2.1

Hardware Description

The EVB-USB2517 has one onboard regulator, which generates 3.3 volts from an external 5 volt power

supply. The USB2517 generates its own on-chip 1.8 volt supply. The internal 1.8 volt regulator to the

oscillator and the PLL is turned off during suspend to minimize suspend current. The USB2517 hub

consumes power from the 3.3 volt supply. Downstream port power is distributed by four power switches

(U1, U2, U6 and U7) that consume power from the 5 volt supply.

2.1.1

Port Assignment

Downstream ports are numbered one through seven with individual port power controllers. The port

power controllers provide 5 volts of power with over-current protection to the downstream devices.

Upstream and downstream port connectors have USB 2.0 compliant decoupling and a separate shield

ground.

2.1.2

Hub Configuration

Default: The EVB-USB2517 has been set up to support internal default configuration with no strapping

options enabled as determined by the state of CFG_SEL2, CFG_SEL1 and CFG_SEL0 pins

immediately after reset.

U5. To enable this option, change the states of CFG_SEL2 and CFG_SEL1. Program and install an

EEPROM at U5. This option allows access to all of the configuration registers and ID strings for the

USB2517 device for detailed and desired functional analysis and exercise. The EVB-USB2517 is

bytes.

2.1.3

Port Power LEDs

LEDs 9,10,11,12,16,17, and 18 can be arranged to indicate when port power is available. This feature

is optional and consumes power in suspend mode. The recommendation is to leave this feature

unpopulated for low-cost and low-power implementations.

2.1.4

Hi-Speed Indicator LED

A red LED, LED14 or LED15 (depending on the strapping of HS_IND/CFG_SEL1), indicates when the

hub’s upstream port is connected at Hi-Speed.

2.1.5

Powered State LED

An optional LED, LED13, indicates when power is present.