The device contains four multicontroller Inter-Integrated Circuit (I2C) controllers. Each I2C controller was designed to be compliant to the Philips I2C-bus™ specification version 2.1. However, the device IOs are not fully compliant to the I2C electrical specification. The speeds supported and exceptions are described per port below:
- I2C1, I2C2, and I2C3
- Speeds:
- Standard-mode (up to 100 Kbits/s)
- Fast-mode (up to 400 Kbits/s)
- Exceptions:
- The IOs associated with these ports are not compliant to the fall time requirements defined in the I2C specification because they are implemented with higher performance LVCMOS push-pull IOs that were designed to support other signal functions that could not be implemented with I2C compatible IOs. The LVCMOS IOs being used on these ports are connected such they emulate open-drain outputs. This emulation is achieved by forcing a constant low output and disabling the output buffer to enter the Hi-Z state.
- The I2C specification defines a maximum input voltage VIH of (VDDmax + 0.5 V), which exceeds the absolute maximum ratings for the device IOs. The system must be designed to ensure the I2C signals never exceed the limits defined in the Absolute Maximum Ratings section of this datasheet.
- I2C0
- Speeds:
- Standard-mode (up to 100 Kbits/s)
- Fast-mode (up to 400 Kbits/s)
- Exceptions:
- The IOs associated with this port were not design to support Hs-mode.
- The rise and fall times of the I2C signals connected to these ports must not exceed a slew rate of 0.8 V/ns (or 8E+7 V/s). This limit is more restrictive than the minimum fall time limits defined in the I2C specification. Therefore, it may be necessary to add additional capacitance to the I2C signals to slow the rise and fall times such that they do not exceed a slew rate of 0.8 V/ns.
- The I2C specification defines a maximum input voltage VIH of (VDDmax + 0.5 V), which exceeds the absolute maximum ratings for the device IOs. The system must be designed to ensure the I2C signals never exceed the limits defined in the Absolute Maximum Ratings section of this datasheet.
Refer to the Philips I2C-bus specification version 2.1 for timing details.
For more details about features and additional description information on the device Inter-Integrated Circuit, see the corresponding subsections within Signal Descriptions and Detailed Description sections.