A FILTER AND A SWITCHING CIRCUIT

摘要

The present invention provides in an in-line filter for coupling a voice frequency equipment (VFE) to a transmission line that can be used for transmission of DSL data and telephone signals. The filter comprises electronic components that are arranged so that signal attenuation at a predetermined frequency range is provided when the VFE is off-line. The present invention also provides a switching circuit that may be used for such a filter. The switching circuit is bidirectional and has switching properties for a first current direction that are independent from the switching properties for a current in the reverse direction.