Patent · US Expired

Multiplexer commutated high pass filter

US4031506A · kind A · utility

13Cited by
5References
7Claims
0Family size

Assignee

Inventor

Key dates

Filing dateMar 8, 1976
Grant dateJun 21, 1977
Priority date
Expiry dateMar 8, 1996

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04L25/4904
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

A multi-channel analog system comprises a plurality of channels each being adapted to receive analog signals from a signal source such as a seismic sensor. A multiplexer multiplexes the analog channels prior to converting the channels' signals into digital numbers. Each channel has a DC blocking capacitor connected to one terminal of a normally-open multiplexer switch; the other terminal of the switch is coupled to a multiplexer bus. In accordance with this invention, the bus is connected to a common resistor. Control means consecutively close the multiplexer switches so that the capacitor whose switch has been closed forms a high-pass filter with the common resistor. The resistor is preferably connected as the input resistor to an operational amplifier. The capacitors, the multiplexer, and the common resistor form a multiplexer-commutated high-pass filter which is particularly adapted for multi-channel seismic systems.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.