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

At least one output current source or sink for an implantable stimulator device, comprising:

• a first input path for receiving a reference current;
• a first output path for providing an output current to a first electrode of the implantable stimulator device, wherein the first electrode is implantable adjacent to tissue to be stimulated, and wherein a magnitude of the output current is dictated by a magnitude of the reference current;
• and
• a first feedback circuit for comparing a first voltage on the first input path and a second voltage on the first output path, wherein the first feedback circuit controls a first transistor in the first output path such that the first transistor operates in a linear mode and not in a saturation mode.

At least one output current source or sink for an implantable stimulator device, comprising:

• a first input path comprising a first load coupled to a power supply for receiving a reference current;
• a first output path comprising a second load coupled to the power supply and a transistor, wherein the first output path comprises an output current coupled to a first electrode of the implantable stimulator device, wherein the first electrode is implantable adjacent to tissue to be stimulated;
• and
• a first feedback circuit for comparing a first voltage on the first input path and a second voltage on the first output path, wherein the first feedback circuit controls the transistor such that the transistor operates in a linear mode and not in a saturation mode.