User manual

9
Copyright © 2012 Future Technology Devices International Limited
RPi HUB Module Datasheet
Version 1.0
Document Reference No.: FT_000700 Clearance No.: FTDI# 297
In most cases, the FT2232H pin is connected directly to the associated pin on J1 or J2.
There are also several LEDs available on the FT2232H Hub-I/O to indicate the status of power and USB
hub port. Detailed functions of LEDs are described in Table 3.4.
LED Reference
Designator
Colour
Function Description
POWER
Yellow
Power active to downstream USB ports indicator
PORT1
Red
Overcurrent status of downstream USB port 1 indicator
PORT1
Green
Enumeration status of downstream USB port 1 indicator
PORT2
Green
Enumeration status of downstream USB port 2 indicator
PORT2
Red
Overcurrent status of downstream USB port 2 indicator
Figure 3.4 Functions of status LEDs on the module
4 Guide to Supplying Power
When RPi HUB Module is connected to Raspberry Pi board it must be powered from external +5V power
supply. The Raspberry Pi board can be powered by connecting P1-02 header to J2-24 on RPi HUB Module.
To date, the Raspberry Pi uses a 140mA fuse on the power line to the USB connector; this fuse will not
allow an adequate amount of current to power the RPi HUB Module from this USB connector.
USB Bus powered configuration may be used with other host devices, such as PCs or laptops. To enable
external power supply feature, switch the jumper JP1 and JP2 to SELF position, pins 2 & 3 shorted for
both jumpers. The maximum total current consumed by the external USB devices on downstream port 1
and 2 is 1A. If the total current exceeds 1A, the fuse on the RPi HUB Module will disconnect the power to
the USB downstream ports. If this occurs then LEDs PORT1 and PORT2 on the module will illuminate red
to indicate over-current status.
When powered from USB bus power, the estimated current consumed by the circuits on the module is
between 100-300mA depending on the application. User should ensure that the host can supply this
current via USB potation.