MIC2505_04 Datasheet, PDF (10/12 Pages) Micrel Semiconductor – Single 2A / Dual 1A / High-Side Switches

MIC2505/2506
Applications Information
USB Application
Figure 4 depicts a low cost and robust implementation of a
four-port, self-powered USB hub circuit employing ganged
overcurrent protection.
Micrel
(+)
4.45V to 5.25V
3.5A max.
(–)
V_BUS
D+
D–
GND
33µF _MIC5203-3.3
MIC5207-3.3
LDO Regulator
IN
OUT
GND
4.7
µF
Bold lines indicate
0.1" wide, 1-oz. copper
high-current traces.
100k
3.3V USB Controller
V+
ON/OFF
1.0 _OVERCURRENT
µF
D+
D– _GND
MIC2505-2/-1
EN
FLG
GND
GATE
OUT
IN
OUT
IN
33µF
0.1µF
33µF
Ferrite
Bead
0.01µF
V_BUS
D+
D–
GND
0.01µF
V_BUS
D+
D–
GND
33µF
0.01µF
V_BUS
D+
D–
GND
33µF
0.01µF
V_BUS
D+
D–
GND
Data
Figure 4. Ganged-Switch Self-Powered Hub
Downstream
USB
Port 1
500mA max.
Downstream
USB
Port 2
500mA max.
Downstream
USB
Port 3
500mA max.
Downstream
USB
Port 4
500mA max.
M9999-042704
10
April 2004