Title :
A Low-Noise Trunk Interface Circuit
Author :
Smolka, G.J. ; Grehl, U. ; Jahn, B. ; Riedle, U. ; Veit, W. ; Werker, H.
Author_Institution :
Siemens AG, Component Group, Balanstr. 73, D-8000 Munich 80, Germany
Abstract :
A fully analog trunk-interface circuit with wide dynamic range is described. It is on an analog line card of a PABX. The circuit suppresses meter pulses in the voice channel and contains filters for hybrid balancing and impedance matching. Meter and ringing signals are filtered and detected. All the filter functions are implemented in a continuous-time MOSFET-C technique with automatic on-chip tuning. The four-transistor structure used has not been realized in silicon before.
Keywords :
Band pass filters; Communication networks; Dynamic range; Frequency; ISDN; Impedance matching; Low pass filters; MOSFET circuits; Pulse amplifiers; Silicon;
Conference_Titel :
Solid-State Circuits Conference, 1991. ESSCIRC '91. Proceedings - Seventeenth European
Conference_Location :
Milan, Italy
