The TEA1112 and TEA1112A are bipolar transmission circuits for use in electronic telephone sets. They are added to the range of well-known transmission circuits of the TEA1060-family. This report contains a detailed description of the circuit blocks of the TEA1112 and TEA1112A. Two application examples of the TEA1112 are given. The report handles the consecutive steps to design or to adjust the basic application with these ICs. The EMC behaviour of an evaluation board with the TEA1112 or TEA1112A is included. The general notation in this report for both ICs, TEA1112 and TEA1112A, is: TEA1112/A.