Low power loss current digital-to-analog converter used in an implantable pulse generator

摘要

An implantable stimulation device that includes output current sources and/or sinks configured to provide an output current for a load (i.e., tissue). The output path of the output current source or sink comprises a transistor which operates in a linear mode instead of a saturation mode. Because operation in a linear mode results in smaller drain-to-source voltage drops, power consumption in the output current source or sink (and hence in the implantable stimulator) is reduced, reducing battery or other power source requirements. Operation in the linear mode is facilitated by a load in an input path and a load in the output path (which bears the output current). The loads can be active transistors or passive resistors. A feedback circuit (e.g., an operational amplifier) receives voltages that build up across these loads, and sends a control signal to the gate of the transistor to ensure its linear operation.

主权项

1. An implantable stimulator device, comprising:
a first electrode implantable adjacent to tissue to be stimulated; at least one first transistor configured to source a stimulation current along a first output path to the first electrode; a second electrode implantable adjacent to tissue to be stimulated; and at least one second transistor configured to sink the stimulation current along a second output path from the second electrode, wherein the at least one first transistor and the at least one second transistor are controlled to operate in a linear mode.