Philips ISP1520

Philips Semiconductors ISP1520

Hi-Speed USB hub controller

Product data Rev. 03 — 24 November 2004 13 of 51

9397 750 13701 © Koninklijke Philips Electronics N.V. 2004. All rights reserved.

9.1.2 Power switching

Powerswitching of downstream ports can be done individually or ganged, where all

ports are simultaneously switched with one power switch.The ISP1520 suppor ts both

modes, which can be selected using input PSWn_N; see Tab le 5.

Voltage drop requirements:Self-powered hubs are required to provide a minimum

of 4.75 V to its output port connectors at all legal load conditions. To comply with

Underwriters Laboratory Inc. (UL) safety requirements, the power from any port must

be limited to 25 W (5 A at 5 V). Overcurrent protection may be implemented on a

global or individual basis.

Assuming a 5 V ±3 % power supply, the worst-case supply voltage is 4.85V. This

only allows a voltage drop of 100 mV across the hub Printed-Circuit Board (PCB) to

each downstream connector. This includes a voltage drop across the:

•Power supply connector

•Hub PCB (power and ground traces, ferrite beads)

•Power switch (FET on-resistance)

•Overcurrent sense device.

The PCB resistance and power supply connector resistance may cause a drop of

25 mV, leaving only 75mV as the voltage drop allowed across the power switch and

overcurrent sense device. The individual voltage drop components are shown in

Figure 5.

For global overcurrent detection, an increased voltage drop is needed for the

overcurrent sense device (in this case,a low-ohmic resistor). This can be realized by

using a special power supply of 5.1 V ±3 %, as shown in Figure 6.

(1) Includes PCB traces, ferrite beads, and so on.

Fig 5. Typical voltage drop components in the self-powered mode using individual overcurrent detection.

5 V

POWER SUPPLY

± 3 % regulated −

+4.85 V (min)

004aaa261

low-ohmic

PMOS switch

ISP1520

power switch

(PSWn_N)

VBUS

D+

D−

GND

SHIELD

4.75 V (min)

downstream

port

connector

hub board

resistance

voltage drop

25 mV

voltage drop

75 mV

(1)

(1) Includes PCB traces, ferrite beads, and so on.

Fig 6. Typical voltage drop components in the self-powered mode using global overcurrent detection.

5.1 V KICK-UP

POWER SUPPLY

± 3 % regulated −

+4.95 V (min)

004aaa262

low-ohmic

PMOS switch

ISP1520

power switch

(PSWn_N)

VBUS

D+

D−

GND

SHIELD

4.75 V (min)

downstream

port

connector

hub board

resistance

voltage drop

25 mV

voltage drop

75 mV

low-ohmic

sense resistor

for overcurrent

detection

voltage drop

100 mV

(1)

Contents

Main ISP1520 Hi-Speed Universal Serial Bus hub controller Universal Serial Bus Specication Rev.2.0 Rev. 03 24 November 2004 Product data 1. General description 2. Features Universal Serial Bus Specication Rev.2.0 3. Applications 4. Abbreviations 5. Ordering information Product data Rev. 03 24 November 2004 4 of 51 6. Block diagram Fig 1. Block diagram. ISP1520 Philips Semiconductors ISP1520 Product data Rev. 03 24 November 2004 5 of 51 7. Pinning information ISP1520BD Fig 2. Pin conguration. 7.2 Pin description 7.1 Pinning Page ISP1520 Hub Demo Board Users Guide Page 8. Functional description 8.3 Phase-locked loop clock multiplier 8.4 I2C-bus controller 8.5 Overcurrent detection circuit 8.6 GoodLink 8.7 Power-on reset Fig 4. External clock with respect to power-on reset. Fig 3. Power-on reset timing. Stable external clock is to be available at A. POR EXTERNAL CLOCK A 9. Conguration selections 9.1 Conguration through I/O pins Page Philips Semiconductors ISP1520 9.2 Device descriptors and string descriptors settings using I2C-bus The I C-bus specication Page 9.2.3 ROM or EEPROM map Page Page Philips Semiconductors ISP1520 Page 10. Hub controller description 11. Descriptors Page Page 12. Hub requests Tab le 23 shows the suppor ted standard USB requests. 12.1 Standard USB requests 12.2 Hub class requests Tab le 24 shows the hub class requests. 12.3 Detailed responses to hub requests Page Page 12.4 Various get descriptors bmRequestType 10000000B bmRequest GET_DESCRIPTOR = 6 13. Limiting values 14. Recommended operating conditions In accordance with the Absolute Maximum Rating System (IEC 60134). 15. Static characteristics Page Page 16. Dynamic characteristics C; test circuit Figure 21; unless otherwise specied. Page TPERIOD is the bit duration corresponding with the USB data rate. Fig 11. Source differential data-to-EOP transition skew and EOP width. TPERIOD is the bit duration corresponding with the USB data rate. tJR is the jitter reference point. Fig 13. Receiver SE0 width tolerance. Fig 12. Receiver differential data jitter. Fig 14. Hub differential data delay and SOP distortion. Fig 15. Hub EOP delay and EOP skew. and T within recommended operating range; V 5 V; V =V ; V 17. Application information 17.1 Descriptor conguration selection ISP1520 Fig 18. Adjusting analog overcurrent detection limit (optional). ISP1520 17.3 Self-powered hub congurations ISP1520 Fig 19. Self-powered hub; individual port power switching; individual overcurrent detection. Fig 20. Self-powered hub; ganged port power switching; global overcurrent detection. ISP1520 18. Test information DMn D Fig 22. Full-speed test circuit. Fig 21. High-speed transmitter and receiver test circuit. 19. Package outline LQFP64: plastic low profile quad flat package; 64 leads; body 10 x 10 x 1.4 mm SOT314-2 Fig 23. LQFP64 package outline. c 20. Soldering 20.1 Introduction to soldering surface mount packages Data Handbook IC26; Integrated Circuit Packages 20.2 Reow soldering 20.3 Wave soldering 21. Revision history Contact information 22. Data sheet status 23. Denitions 24. Disclaimers 25. Licenses 26. Trademarks Contents