Patent ID: 7170727

Claim:
An input pad for differential current signals on an integrated circuit comprising: a first input; a second input; an upper reference voltage set to an upper fixed voltage value; a lower reference voltage set to a lower fixed voltage value; a first primary ESD protection circuit connected to said first input and also connected to said upper reference voltage and to said lower reference voltage; a second primary ESD protection circuit connected to said second input and also connected to said upper reference voltage and to said lower reference voltage; a first amplifier having a first connection to said first ESD protection circuit and having an output; a second amplifier having a second connection to said second ESD protection circuit and having an output; a common mode rejection circuit that is connected to said first connection between said first ESD protection circuit and said first amplifier and said second connection between said second ESD protection circuit and said second amplifier, said common mode rejection circuit further having a first output and a second output, and said first ESD protection circuit and said second ESD protection circuit not included as part of said common mode rejection circuit; a first output connected to said first output of said common mode rejection circuit and said output of said first amplifier, said output of said first amplifier not coupled to said first output through said common mode rejection circuit, and said first output not connected to said first ESD protection circuit; and a second output connected to said second output of said common mode rejection circuit and said output of said second amplifier, said output of said second amplifier not coupled to said second output through said common mode rejection circuit, and said second output not connected to said second ESD protection circuit.