Philips ISP1122 10. I2C-bus interface

Philips Semiconductors ISP1122

USB stand-alone hub

Product speciﬁcation Rev. 03 — 29 March 2000 20 of 48

9397 750 07002 © Philips Electronics N.V. 2000. All rights reserved.

9.4.6 Get conﬁguration descriptor

The hub returns 25 bytes containing the conﬁguration descriptor (9 bytes, see

Tab le 11), the interface descriptor (9 bytes, see Ta ble 12 )and the endpoint descriptor

(7 bytes, see Tab le 13).

9.4.7 Get device descriptor

The hub returns 18 bytes containing the device descriptor, see Tab le 10.

9.4.8 Get hub descriptor

The hub returns 9 bytes containing the hub descriptor, see Tab le 14.

9.4.9 Get string descriptor (0)

The hub returns 4 bytes containing the language ID, see Tab le 15.

9.4.10 Get string descriptor (1)

The hub returns 46 bytes containing the manufacturer name, see Tab le 15.

9.4.11 Get string descriptor (2)

The hub returns 16 bytes containing the product name, see Tab le 15 .

10. I2C-bus interface

A simple I2C-bus interface is provided in the ISP1122 to read customized vendor ID,

product ID and some other conﬁguration bits from an external EEPROM. The

interface supports single master operation at a nominal bus speed of 93.75 kHz.

The I2C-bus interfaceis intended for bidirectional communication between ICs via two

serial bus wires, SDA (data) and SCL (clock). Both lines are driven by open-drain

circuits and must be connected to the positive supply voltage via pull-up resistors.

10.1 Protocol

The I2C-bus protocol deﬁnes the following conditions:

•Bus free: both SDA and SCL are HIGH

•START: a HIGH-to-LOW transition on SDA, while SCL is HIGH

•STOP: a LOW-to-HIGH transition on SDA, while SCL is HIGH

•Data valid: after a START condition, data on SDA are stable during the HIGH

period of SCL; data on SDA may only change while SCL is LOW.

Each device on the I2C-bus has a unique slave address, which the master uses to

select a device for access.

The master starts a data transfer using a START condition and ends it by generating

a STOP condition. Transfers can only be initiated when the bus is free. The receiver

must acknowledge each byteby means of a LOW level on SDA during the ninth clock

pulse on SCL.

For detailed information please consult

The I

2

C-bus and how to use it

., order number

9398 393 40011.

Contents

Main ISP1122 Universal Serial Bus stand-alone hub Universal Serial Bus Specication Rev. 1.1 USB Specication Rev. 1.1 Rev. 03 29 March 2000 Product specication 3. Ordering information 4. Block diagram This is a conceptual block diagram and does not include each individual signal. th ISP1122 5. Pinning information 5.1 ISP1122D (SO32) and ISP1122NB (SDIP32) Fig 2. Pin conguration SO32. Fig 3. Pin conguration SDIP32. 5.1.2 Pin description 5.1.1 Pinning Page Page 5.2 ISP1122BD (LQFP32) 5.2.1 Pinning Fig 4. Pin conguration LQFP32. 5.2.2 Pin description ISP1122BD Page 6. Functional description 6.1 Analog transceivers USB Specication Rev. 1.1 6.2 Philips Serial Interface Engine (SIE) 6.3 Hub repeater USB Specication Rev. 1.1 6.4 End-of-frame timers 6.5 General and individual port controller 7. Modes of operation Philips Semiconductors ISP1122 8. Endpoint descriptions 8.1 Hub endpoint 0 (control) 8.2 Hub endpoint 1 (interrupt) Philips Semiconductors ISP1122 9. Host requests 9.1 Standard requests 9.2 Hub specic requests Page 9.3 Descriptors The ISP1122 hub controller supports the following standard USB descriptors: USB Specication Rev. 1.1 Page USB Specication Rev. 1.0 9.4 Hub responses Page 10. I2C-bus interface 10.1 Protocol C-bus and how to use it The I 10.2 Hardware connections 10.3 Data transfer Philips Semiconductors ISP1122 11. Hub power modes USB Specication Rev.1.1 11.1 Voltage drop requirements 12. Overcurrent detection 12.1 Overcurrent circuit description 12.2 Power switch selection 12.3 Tuning the overcurrent trip voltage 12.4 Reference circuits Power switches 1 to 5 are low-ohmic PMOS devices as specied inSection 12.2. ISP1122 Fig 10. Mode 5: self-powered hub; individual port power switching; individual overcurrent detection. Power switch is low-ohmic PMOS device as specied inSection 12.2. Fig 11. Mode 1: self-powered hub; ganged port power switching; global overcurrent detection. Power switches 1 to 4 are low-ohmic PMOS devices as specied inSection 12.2. Fig 12. Mode 4: bus-powered hub; individual port power switching; individual overcurrent detection. Product specication Rev. 03 29 March 2000 29 of 48 Power switch is low-ohmic PMOS device as specied inSection 12.2. Fig 13. Mode 0: bus-powered hub; ganged port power switching; global overcurrent detection. 13. Limiting values In accordance with the Absolute Maximum Rating System (IEC 60134). 14. Static characteristics 15. Dynamic characteristics =0V;T on D = 1.5 k C; C = 50 pF; R =0V;T on D = 1.5 k C; C = 50 pF; R Fig 15. Source differential data jitter. Fig 16. Source differential data-to-EOP transition skew and EOP width. Fig 17. Receiver differential data jitter. Fig 18. Receiver SE0 width tolerance. Fig 19. Hub differential data delay and SOP distortion. [1] fSCL =164fXTAL. [2] Rise time is determined by Cb and pull-up resistor value Rp (typ. 4.7 k). Fig 20. Hub EOP delay and EOP skew. DD SS IH IL 16. Test information Fig 22. Load impedance for D+ and D- pins. Fig 21. I2C-bus timing. 17. Package outline Fig 23. SO32 package outline. SO32: plastic small outline package; 32 leads; body width 7.5 mm SOT287-1 SDIP32: plastic shrink dual in-line package; 32 leads (400 mil) SOT232-1 Fig 24. SDIP32 package outline. LQFP32: plastic low profile quad flat package; 32 leads; body 7 x 7 x 1.4 mm SOT358-1 Fig 25. LQFP32 package outline. c 18. Soldering 18.1 Introduction Data Handbook IC26; Integrated Circuit Packages 18.2 Surface mount packages 18.3 Through-hole mount packages 18.4 Package related soldering information 19. Revision history 20. Data sheet status 21. Denitions 22. Disclaimers 23. Licenses 24. Trademarks Philips Semiconductors - a worldwide company Internet: http://www.semiconductors.philips.com Contents