DS00001726B-page 15

USB2422

3.2

Battery Charging Configuration

The battery charging option can be configured in one of two ways:

• When the hub is brought up in the default configuration with strapping options enabled, with the PRTP-

WR1/BC_EN1 pin configured (Port 1 only). See the following sections for details:

- Section 2.3, "Pin Descriptions (Grouped by Function)," on page 7

- Section 2.5, "Strap Pin Configuration," on page 10

• When the hub is initialized for configuration over SMBus.

3.2.1

BATTERY CHARGING ENABLED VIA SMBUS

Register memory map location 0xD0 is allocated for battery charging support. The Battery Charging register at location

0xD0 starting from bit 1 enables battery charging for each downstream port when asserted. Bit 1 represents port 1, and

bit 2 represents port 2. Each port that has battery charging enabled asserts the corresponding PRTPWR[2:1] pin.