Current generation architecture for an implantable stimulator device to promote current steering between electrodes

A method for controlling a pulse generator having a plurality of electrode nodes, each electrode node configured to be coupled to a corresponding electrode configured to contact a patient's tissue, the method comprising:

• providing a first current to each of a plurality of first digital-to-analog converters (DACs), wherein each of the first DACs is dedicated to provide an anodic stimulation current to a different dedicated one of the electrode nodes, wherein each first current has a magnitude indicative of a total anodic current amplitude to be produced at the electrode nodes, wherein each first DAC comprises a plurality of first branches;
• and
• selecting one or more first branches in at least one of the first DACs to produce an amplified version of the first current, wherein the amplified first current at each selected first branch in each of the first DACs is summed to produce the anodic stimulation current at its dedicated electrode.

A method for controlling a pulse generator having a plurality of electrode nodes, each electrode node configured to be coupled to a corresponding electrode configured to contact a patient's tissue, the method comprising:

• providing a first current to each of a plurality of first digital-to-analog converters (DACs), wherein each one of the first DACs is dedicated to provide an anodic stimulation current to a different dedicated one of the electrode nodes, wherein each first current has a magnitude indicative of a total anodic current amplitude to be produced at the electrode nodes;
• providing a plurality of first control signals to each of the first DACs, wherein the first control signals indicate a percentage of the total anodic current amplitude that each first DAC will produce as the anodic stimulation current at its dedicated electrode node.