MC3419-1 The Subscriber Loop Interface Circuit Family (SLIC) The replacement of two-to-four wire conversion with hybrid transformers in Central Office, PBX, and Subscriber Carrier equipment has resulted in major improvement in telephony equipment. The SLIC family performs this task, along with all the other BORSHT functions required by sig- nal transmission. These include the provision of dc power to the telephone (Battery); Overvoltage protection; Ring trip detection; Supervisory features such as hook status and dial pulsing; 2-to-4 wire conversion, suppression of longi- tudinal signals (Hybrid); and Testing. The various type numbers signify differences in longitu- dinal balance specifications. Crosspoint Switches Todays semiconductor Crosspoint switches, im- plemented with semiconductor technology, take the place of the huge banks of mechanical relay matrices once utilized in Central Offices and PBXs. Motorola provides a choice of three configurations to meet specific system design goals. CASE 726 CERAMIC PACKAGE gotten Hook Status Contro: Crreut HST FoI Bz Miror \ ! V ne 1 [a2 Mirror TSAC MONO- CIRCUIT Rrxy Balance Network Analog Ground Receive Input Transit Output Device Description Pins | Suffix MC142100/ ICMOS 4x 4x 1 Matrix; Comple-| 16 L,P 145100 mentary Transistor Ceils MC142101 CMOS 4x 4x 2 Matrix 24 |} L,P Note: L = Ceramic, P = Plastic MOTOROLA EUROPEAN MASTER SELECTION GUIDE 2-31