Patent ID: 7257222

Claim:
A ring voltage generation circuit for generating a ring voltage signal between a TIP lead and a RING lead; comprising: a) an amplifier circuit configured to receive an input voltage signal and to amplify the input voltage signal in order to generate the ring voltage signal; b) an absolute value generator configured to receive the input voltage signal and to generate a measured absolute value of the input voltage signal; c) a DC/DC converter configured to receive the measured absolute value of the input voltage signal and to convert the measured absolute value into a supply voltage for the amplifier circuit, the DC/DC converter operably coupled to provide the supply voltage to a supply input of the amplifier circuit; and d) a common mode feedback device configured to receive the supply voltage, a TIP potential of the TIP lead and a RING potential of the RING lead, and further configured to generate a control voltage based on the received supply voltage, TIP potential of the TIP lead, and RING potential, wherein the common mode feedback device is operable to control the amplifier circuit using the control voltage.