Using MCC I2C Bus Adapters in SMBus Applications

Using MCC I²C Bus Adapters in SMBus Applications

MCC I²C Bus adapters are designed to meet I²C Bus Specifications. SMBus is based upon the I²C Bus Specification, but includes some additional rules primarily designed to help support master devices operating in a multi-master environment. With the following considerations, our I²C Bus adapters can be used in many SMBus applications.

In regard to SMBus V1.0, V1.1, and V2.0 Specifications, our I2C Bus adapters:

1. Do not implement the SMBus 35 millisecond slave device time-out.
2. Can be directed to operate faster than the maximum SMBus 100 KHz clock rate.
3. Can operate slower than the minimum SMBus 10 KHz clock rate.
4. Have a minimum signal high voltage of 3.3V, as compared to SMBus 2.1V.

Note: With the addition of our iVoLT (#IVOLT, Datasheet) Voltage Level Translator, our I²C Bus adapters can operate with a minimum signal high voltage of 1.5V.
5. Can sink up to 3 mA on Clock and Data signals, as compared to SMBus 350 uA.
6. Do not automatically support the optional SMBus slave device Suspend Mode (SMBSUS#) signal.
7. Do not automatically support the optional SMBus slave device Alert Response (SMBALERT#) signal.

Note: Our I²C Bus adapters support the /INTERRUPT signal which can be used to support SMBSUS# or SMBALERT# signals.
8. Do not automatically support the SMBus (V1.1) Packet Error Check byte slave device processing.
9. Do not automatically support the SMBus (V2.0) Address Resolution Protocol.

• A comparison of I²C Bus and SMBus (http://dbserv.maxim-ic.com/appnotes.cfm?appnote_number=476).
• I²C Bus Specifications (http://www.nxp.com/acrobat/usermanuals/UM10204_3.pdf).
• SMBus Specifications (http://www.smbus.org/specs/).