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TMUXHS4412: Common mode voltage limits

Part Number: TMUXHS4412

Hello, 

Please refer to the diagram below. 

We would like to use the TMUXHS4412 to be able to support both SFP+ and CSFP+ modules.

With CSFP+, 3 control signals(RS0,RS1,MOD) and 1 gnd (Vee) signal of the SFP+ interface are used for the 10Gbps lane.

With SFP+, these control signals should be pulled high to +3.3V. According to the datasheet, however, the max recommended common mode voltage of the TMUXHS4412 is limited to 1.8V, while the absolute maximum is 2.5V.

Since the VIH of the SFP+ inputs is 2.3V, my idea is to set the input common voltage to 2.4V, which is over the recommended but less than absolute maximum. 

1) Do you see any issues with this kind of connection? 

2) What are the consequences, in this case, of working outside the recommended range? Recall that these are just control inputs and do not pass any high speed signals. The high speed signals are routed through the DB0 and DB1 ports. 

3) Can I connect DA0n directly to GND? 

Thank you in advance.