Philips Semiconductors ISP1122
USB stand-alone hub
Product specification Rev. 03 — 29 March 2000 27 of 48
9397 750 07002 © Philips Electronics N.V. 2000. All rights reserved.

Power switch is low-ohmic PMOS device as specified inSection 12.2.

Fig 11. Mode 1: self-powered hub; ganged port power switching; global overcurrent detection.
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book, full pagewidth
MGR785
INDV
OPTION
PSW1/GL1
PSW5/GL5/GPSW
PSW4/GL4
PSW3/GL3
SP/BP
OC5/GOC
PSW2/GL2
OC1
OC2
OC3
OC4
low-ohmic
sense resistor
for overcurrent
detection
ISP1122
5.1 V KICK-UP
POWER SUPPLY
± 3%
++4.95 V(min)
+4.95 V(min) VCC
GND
330
k
VBUS
D+
D
GND
SHIELD
+4.75 V
(min) 1
downstream
ports
120
µF
ferrite bead
VBUS
D+
D
GND
SHIELD
+4.75 V
(min) 2
120
µF
ferrite bead
VBUS
D+
D
GND
SHIELD
+4.75 V
(min) 3
120
µF
ferrite bead
VBUS
D+
D
GND
SHIELD
+4.75 V
(min) 4
120
µF
ferrite bead
VBUS
D+
D
GND
SHIELD
+4.75 V
(min) 5
120
µF
ferrite bead
100
to
1 k
low-ohmic
PMOS switch
47 k
0.1 µF