FPF2300 Fairchild Semiconductor, FPF2300 Datasheet - Page 13

• Manufacturer Part Number: FPF2300
• Manufacturer: Fairchild Semiconductor

© 2009 Fairchild Semiconductor Corporation
FPF2300/02/03 • Rev. 1.1.3
Application Information
FPF230X is designed to simplify USB port power design based
on self-powering USB host/hub applications. A self-powering
USB port is powered by a local 5V power supply, not by an
upstream port. Each port should supply at least 500mA to each
downstream function based on USB 2.0 specification. Imple-
mentation can depend on the number of USB ports and current
In Figure 39, each USB port is connected with each output.
Four USB ports can be implemented with two FPF230X parts.
Current limiting and control are provided based on a single port.
Host
5V
Host
5V
Figure 39. Individual Port Power Management for Self-Powered 4-Port USB Hub
1μF
1μF
1μF
Figure 38. Self Powered 4-Port USB Hub Using a Single FPF230X
OFF ON
OFF ON
OFF ON
OFF ON
OFF ON
OFF ON
IN
ONA
ONB
IN
ONA
ONB
IN
ONA
ONB
FPF2300/2/3
FPF2300/2/3
FPF2300/2/3
13
GND
capability per port required in actual power designs. FPF230X
has 1.1A minimum current limit per output, which can cover two
ports, as shown in Figure 38. Four USB ports can be imple-
mented with a single FPF230X part and current limiting is pro-
vided based on a two-port basis for a cost-effective solution.
Current capability per port has more headroom; up to a mini-
mum of 1.1A per port.
GND
GND
FLAGB(A)
FLAGB(B)
10KΩ
10KΩ
OUTB
OUTA
FLAGB(A)
FLAGB(B)
FLAGB(A)
FLAGB(B)
10KΩ
10KΩ
10KΩ
10KΩ
OUTB
OUTB
OUTA
OUTA
33μF
33μF
33μF
33μF
33μF
33μF
33μF
33μF
Downstream
Downstream
Downstream
Downstream
USB Port
USB Port
USB Port
USB Port
Downstream
Downstream
Downstream
Downstream
USB Port
USB Port
USB Port
USB Port
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