Apparatus for converting analog signals into digital signals and digital signals into analog signals

US4112426A · kind A · utility

Assignee

• Siemens Aktiengesellschaft · DE

Inventors

• Ernst Hofer · Munich, DE
• Klaus Wintzer · Munich, DE

Key dates

• Filing date: Aug 30, 1976
• Grant date: Sep 5, 1978
• Expiry date: Aug 30, 1996

Classification

• Technology area (CPC H): Electricity
• CPC primary: H03M1/146
• WIPO field: Telecommunications
• WIPO sector: Electrical engineering

Abstract

Apparatus for a telecommunication system having subscriber stations constructed to send and receive analog signals which are communicated from one station to the other by means of digital signals is described. Each subscriber station is equipped with a converter for converting received digital signals into analog signals and analog signals into digital signals for transmission. The converter circuit employs an analog to digital converter constructed to work according to the iterative principle and including a binary counter and a buffer register, the stages of which are enabled, respectively, by predetermined counter stage outputs. A digital to analog converter is connected to receive the outputs of the bistable stages forming the buffer register. The counter is connected to trigger the conversion of a received digital signal into an analog signal and subsequently to initiate the conversion of an analog signal into a digital signal; this occurs only after a specified calling bit sequence is received by the converter.