MIC2505 Datasheet, PDF (15/24 Pages) Micrel Semiconductor – Single 2A / Dual 1A / High-Side Switches

MIC2505/6
A gate capacitor may be added to the MIC2505 to slow
the turn on time even more, reducing the inrush
current. See Figure 2-13. The UVLO feature ensures
that each time the card is removed and V_IN = 0 that the
gate of the output switch is discharged to zero volts. A
controlled turn-on is executed each time a board is
plugged in, even with multiple insertions.
6.6 USB Application
Figure 6-4 depicts a low cost and robust
implementation of a four-port, self-powered USB hub
circuit employing ganged overcurrent protection.
(+)
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
33μF
Ferrite
Bead
0.01μF
V_BUS
D+
D–
GND
0.01μF
V_BUS
D+
D–
GND
0.01μF
V_BUS
D+
D–
GND
FIGURE 6-4:
Ganged-Switch Self-Powered Hub.
33μF
0.01μF
V_BUS
D+
D–
GND
Data
Downstream
USB
Port 1
500mA max.
Downstream
USB
Port 2
500mA max.
Downstream
USB
Port 3
500mA max.
Downstream
USB
Port 4
500mA max.
 2016 Microchip Technology Inc.
DS20005579A-page 15