Systems and methods for obtaining substantially simultaneous mult-channel impedance measurements and related applications

A method for use with an implantable system that includes

• a plurality of terminals configured to be connected to a plurality of implantable electrodes via electrical conductors of one or more implantable leads,
• wherein a plurality of different subsets of the implantable electrodes can be used to define a plurality of different electrical pulse delivery vectors, and
• wherein a plurality of different subsets of the implantable electrodes can be used to define a plurality of different sensing vectors;
• a pulse generator configured to produce one or more electrical pulses for delivery via a selected one of the plurality of different electrical pulse delivery vectors at a time;
• a sensing circuit configured to sense a signal indicative of an impedance associated with a selected one of the plurality of different sensing vectors at a time;
• the method comprising:
• selectively connecting outputs of the pulse generator to a selected one of the plurality of different electrical pulse delivery vectors at a time, in a time-multiplexed manner;
• selectively connecting inputs of the sensing circuit to a selected one of the plurality of different sensing vectors at a time, in a time-multiplexed manner;
• selectively connecting an output of the sensing circuit to one of a plurality of separate signal processing channels at a time, in a time-multiplexed manner;
• and
• using the plurality of separate signal processing channels to simultaneously perform signal processing on separate sensed signals, wherein each of the separate sensed signals is indicative of an impedance associated with a separate one of the plurality of different sensing vectors.

An implantable system, comprising:

• a plurality of terminals configured to be connected to a plurality of implantable electrodes via electrical conductors of one or more implantable leads,
• wherein a plurality of different subsets of the implantable electrodes are used to define a plurality of different electrical pulse delivery vectors, and
• wherein a plurality of different subsets of the implantable electrodes are used to define a plurality of different sensing vectors;
• a pulse generator configured to produce one or more electrical pulses for delivery via a selected one of the plurality of different electrical pulse delivery vectors at a time;
• a sensing circuit configured to sense a signal indicative of an impedance associated with a selected one of the plurality of different sensing vectors at a time;
• a plurality of separate signal processing channels each configured to perform signal processing on a sensed signal indicative of an impedance obtained using the sensing circuit;
• a first multiplexer configured to selectively connect outputs of the pulse generator to a selected one of the plurality of different electrical pulse delivery vectors at a time;
• a second multiplexer configured to selectively connect inputs of the sensing circuit to a selected one of the plurality of different sensing vectors at a time;
• and
• a third multiplexer configured to selectively connect an output of the sensing circuit to one of the plurality of separate signal processing channels at a time;
• a controller configured to control the pulse generator, sensing circuitry, signal processing channels and the first, second and third multiplexers to obtain a plurality of impedance signals each of which is associated with a different sensing vector;
• and
• a processor and/or circuitry configured to combine two or more of the plurality of impedance signals to obtain a combined impedance signal.