Subscriber Line Interface Circuit
Original Publication Date: 1984-Jun-01
Included in the Prior Art Database: 2005-Feb-04
A simple subscriber line interface circuit (SLIC) is proposed that withstands specific equipment in different line switching environments, for instance, European requirements, at the cost of a few more electrical components. The basic circuit, schematically represented in Fig. 1, comprises two quasi-identical blocks each one representing a differential operational amplifier, OA1 or OA2, with a gain of 2 and referenced to a voltage level VS1 or VS2, respectively, other than ground. By splitting resistor R1 into two parts, i.e., R11 and R12, side 1 of the basic circuit is double-ended between nodes M and N, while side 2 with resistor R2 is single ended.