Philips Universal Serial Bus ISP1122 - Manual (Page 27)

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 in Section 12.2 .
Fig 11. Mode 1: self-powered hub; ganged port power switching; global overcurrent detection.
dbook, 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 Ω
VBUS
D
+
D −
GND
SHIELD
+
4.75 V
(min)
1
downstream
ports
120
µ F
ferrite bead
VBUS
D
+
D −
GND
SHIELD
+
4.75 V
(min)
2
120
µ F
ferrite bead
VBUS
D
+
D −
GND
SHIELD
+
4.75 V
(min)
3
120
µ F
ferrite bead
VBUS
D
+
D −
GND
SHIELD
+ 4.75 V
(min)
4
120
µ F
ferrite bead
VBUS
D
+
D −
GND
SHIELD
+ 4.75 V
(min)
5
120
µ F
ferrite bead
100
Ω
to
1 k Ω
low-ohmic
PMOS switch
47 k Ω
0.1 µ F