Switch User Manual
Table Of Contents
- 1. General description
- 2. Features
- 3. Applications
- 4. Abbreviations
- 5. Ordering information
- 6. Block diagram
- 7. Pinning information
- 8. Functional description
- 9. Configuration selections
- 10. Hub controller description
- 11. Descriptors
- 12. Hub requests
- 13. Limiting values
- 14. Recommended operating conditions
- 15. Static characteristics
- 16. Dynamic characteristics
- 17. Application information
- 18. Test information
- 19. Package outline
- 20. Soldering
- 21. Revision history
- 22. Data sheet status
- 23. Definitions
- 24. Disclaimers
- 25. Licenses
- 26. Trademarks
Philips Semiconductors
ISP1521
Hi-Speed USB hub controller
Product data Rev. 03 — 24 November 2004 12 of 53
9397 750 13702
© Koninklijke Philips Electronics N.V. 2004. All rights reserved.
The triggering voltage of the POR circuit is 2.03 V nominal. A POR is automatically
generated when V
CC
goes below the trigger voltage for a duration longer than 1 µs.
At t
1
: clock is running and available.
Fig 3. Power-on reset timing.
Stable external clock is to be available at A.
Fig 4. External clock with respect to power-on reset.
004aaa388
t
1
V
CC
2.03 V
0 V
≤ 683 µs
POR
POR
EXTERNAL CLOCK
A
004aaa365