100 V High Performance Amplifiers in BCD Technology for SLIC Applications

The circuits described in this paper are a line driver and a sensing amplifier. They are part of a Subscriber Line Interface Circuit (SLIC) fabricated in BCD technology that operates up to 100 V. The driver requires about 500 μA of quiescent current, can sink and source up to 100 mA, and remains stable for all possible line lengths. The sensing amplifier senses the line current to synthesize both the ac and DC line termination. It achieves a 2 mV offset and a gain-bandwidth product of 2.5 MHz. The adopted mixed technology allows the realization of a compact single chip SLIC.