
Philips Semiconductors ISP1520
Hi-Speed USB hub controller
Product data Rev. 03 — 24 November 2004 7 of 51
9397 750 13701 © Koninklijke Philips Electronics N.V. 2004. All rights reserved.
RESET_N 31 I asynchronous reset input; when reset is active, the internal
switch to the 1.5 kΩ external resistor is opened, and all pins
DPn and DMn are three-state; it is recommended that you
connect to VBUS through an RC circuit; refer to the
schematics in the
ISP1520 Hub Demo Board User’s GuideADOC 32 I analog or digital overcurrent detect selection input; a LOW
selects the digital mode and a HIGH (3.3 Vor 5.0 V) selects
the analog mode
XTAL1 33 I crystal oscillator input (12 MHz)
XTAL2 34 O crystal oscillator output (12 MHz)
GND 35 - ground supply
DM2 36 AI/O downstream facing port2 D− connection (analog)[3]
DP2 37 AI/O downstream facing port 2 D+ connection (analog)[3]
TEST_HIGH 38 - test pin; connect to 3.3 V
VCC1 39 - analog supply voltage 1 (3.3 V)
GND 40 - ground supply
VCC4 41 - cr ystal and PLL supply voltage4 (3.3 V)
GND 42 - ground supply
DM3 43 AI/O downstream facing port3 D− connection (analog)[4]
DP3 44 AI/O downstream facing port 3 D+ connection (analog)[4]
VCC2 45 - transceiver supply voltage 2 (3.3 V)
GND 46 - ground supply
DM4 47 AI/O downstream facing port4 D− connection (analog)[4]
DP4 48 AI/O downstream facing port 4 D+ connection (analog)[4]
NOOC 49 I no overcurrent protection selection input; connect this pin to
HIGH (3.3 V) to select no overcurrent protection; if no
overcurrent is selected, all OCn_N pins must be connected
to VREF(5V0)
GRN4_N 50 I/O output —green LED port indicator (open-drain) for
downstream facing port 4
input — functionof the pin when used as an input is given in
Tabl e 9
AMB4_N 51 I/O output —amber LED port indicator (open-drain) for
downstream facing port 4
input — functionof the pin when used as an input is given in
Tabl e 8
GRN3_N 52 I/O output —green LED port indicator (open-drain) for
downstream facing port 3
input — functionof the pin when used as an input is given in
Tabl e 9
AMB3_N 53 I/O output —amber LED port indicator (open-drain) for
downstream facing port 3
input — functionof the pin when used as an input is given in
Tabl e 8
Table 2: Pin description[1]
…continued
Symbol[2] Pin Type Description