Patent ID: 7530091

Claim:
A VoIP drop amplifier for connecting equipment to a broadband signal, the VoIP drop amplifier comprising: an input connector for accepting a broadband cable signal from a cable system and returning broadband signals to the cable system; a plurality of output connectors including at least one non-essential output connector and at least one essential input connectors, the at least one essential output connector including an output adapted for connection to VoIP telecommunication equipment; an amplification path connecting the input connector to the plurality of output connectors, the amplification path having: a diplex filter for separating the broadband signal into return and forward signals; amplifier circuitry comprising a forward amplifier for amplifying the forward signals; a return path for the return signals; and a splitter for connecting signals traveling on the amplification path to each of the plurality of output connectors; a bypass path connecting the input connector to the at least one essential output connector; a switching circuit for switching between the amplification path and the bypass path; and a dc current and voltage sensing circuit connected to the switching circuit for to selecting the bypass path upon dc current and voltage sensing circuit detecting an abnormal condition and for selecting the amplification path when the dc current and voltage sensing circuit does not detect an abnormal condition, the dc current and voltage sensing circuit comprising: a circuit for detecting total dc current powering the amplifier circuitry; a first comparator circuit for comparing the total dc current powering the amplifier circuitry to a high current limit and generating a first output based on the comparison; a second comparator circuit for comparing the total dc current powering the amplifier to a low current limit and generating a second output based on the comparison, the low current limit being lower than the high current limit; a circuit for monitoring dc voltage supplied to the reverse amplifier and the forward amplifier, and a voltage comparator circuit for comparing dc voltage supplied to the amplifier circuitry to a low voltage limit and for generating an output based on the voltage comparison, the abnormal condition being detected when the first output exceeds the high current limit, the second output is less than the low current limit, or the output based on the voltage comparison detects dc voltage supplied to the amplifier circuitry less than the low voltage limit.