Patent ID: 6922469

Claim:
A communication system, comprising: phone line side circuitry capable of being coupled to a user end of phone lines, the phone line side circuitry being configured to provide an output signal for sending data to the phone lines; powered side circuitry capable of being coupled to the phone line side circuitry through an isolation barrier that comprises a plurality of isolation elements, the powered side circuitry being configured to be isolated from the phone lines in order to satisfy phone line isolation regulatory standards; phone line side integrated ringer circuitry within the phone line side circuitry; and powered side integrated ringer circuitry within the powered side circuitry; wherein the powered side circuitry is configured to communicate a first digital differential signal to at least two of the isolation barrier elements, the at least two isolation barrier elements comprising at least a first isolation capacitor and a second isolation capacitor; wherein the phone line side circuitry is configured to communicate a second digital differential signal to the first isolation capacitor and the second isolation capacitor, wherein the first and second digital differential signals are communicated across the same first and second isolation capacitors so that the first and second isolation capacitors bidirectionally transfer the first and second digital differential signals; wherein the powered side circuitry is further configured to provide a clock signal to the phone line side circuitry through at least one of the plurality of isolation elements; and wherein the powered side circuitry and the phone line side circuitry are further configured so that power is capable of being provided from the powered side circuitry to the phone line side circuitry while still maintaining the isolation required by the phone line isolation regulatory standards.