Pll Clock Multiplier; Overcurrent Detection; I 2 C-Bus Interface; Modes Of Operation - Philips ISP1122A Product Data

Philips Semiconductors

6.9 PLL clock multiplier

6.10 Overcurrent detection

6.11 I

7. Modes of operation

Table 4: Mode selection
Mode INDV OPTION SP/BP
[1]
0 0 0
1 0 0
2 0 1
3 0 1
4 1 0
5 1 0
6 1 1
7 1 1
[1] Port power switching: logic 0 = ganged, logic 1 = individual.
[2] Power mode: logic 0 = bus-powered, logic 1 = self-powered (or hybrid-powered).
[3] No overcurrent detection.
[4] No power switching.
9397 750 08958
Product data
A 6 to 48 MHz clock multiplier Phase-Locked Loop (PLL) is integrated on-chip. This
allows for the use of low-cost 6 MHz crystals. The low crystal frequency also
minimizes Electro-Magnetic Interference (EMI). The PLL requires no external
components.
An overcurrent detection circuit for downstream ports has been integrated on-chip. It
is self-reporting, resets automatically, has a low trip time and requires no external
components. Both individual and global overcurrent detection are supported.
2
C-bus interface
2
A basic serial I C-bus interface (single master, 100 kHz) is provided to read VID, PID
and configuration bits from an external I
equivalent). At reset the ISP1122A reads 6 bytes of data from the external memory.
2
The I C-bus interface timing complies with the standard mode of operation as
2
described in The I C-bus and how to use it , order number 9398 393 40011.
The ISP1122A has several modes of operation, each corresponding with a different
pin configuration. Modes are selected by means of pins INDV, OPTION and SP/BP,
as shown in Table 4.
PSWn/GLn
[2]
(n = 1 to 4)
0 GoodLink
1 GoodLink
0 GoodLink
[4]
1 GoodLink
0 individual power
1 individual power
0 individual power
[4]
1 GoodLink
Rev. 03 — 30 October 2001
2
C-bus EEPROM (e.g. Philips PCF8582 or
PSW5/GL5/GPSW OCn
(n = 1 to 4)
ganged power inactive
ganged power inactive
ganged power inactive
[4]
GoodLink inactive
inactive individual
overcurrent
individual power individual
overcurrent
inactive inactive
[4]
GoodLink individual
overcurrent
ISP1122A
USB stand-alone hub
OC5/GOC
global overcurrent
global overcurrent
[3] [3]
inactive
global overcurrent
inactive
individual
overcurrent
[3] [3]
inactive
individual
overcurrent
© Koninklijke Philips Electronics N.V. 2001. All rights reserved.
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