Wave shaping for an implantable medical device

A method for generating a neurological stimulation waveform with an implantable medical device, the method comprising the steps of:

• (a) identifying a portion of a rate period interval;
• (b) partitioning the portion into a plurality of phases;
• and
• (c) approximating the neurological stimulation waveform during a first phase in accordance with at least one parameter, the portion of the rate period interval comprising the plurality of phases.

A computer-readable medium containing instructions for controlling a computer system to generate a neurological stimulation waveform with an implantable medical device, the instructions performing the steps of:

• (a) identifying a portion of a rate period interval;
• (b) partitioning the portion into a plurality of phases;
• and
• (c) approximating the neurological stimulation waveform during a phase in accordance with at least one parameter, the portion of the rate period interval comprising the plurality of phases.

An apparatus for generating a neurological stimulation waveform with an implantable medical device, comprising in combination:

• a waveform generator, the waveform generator comprising a regulator module and a digital to analog converter (DAC);
• and
• a waveform controller coupled to the waveform generator, the waveform controller configured to perform the steps of:
• (a) identifying a portion of a rate period interval;
• (b) partitioning the portion into a plurality of phases;
• (c) determining an approximate value of the neurological stimulation waveform during a phase;
• (d) subtracting the approximate value from a constant value in order to obtain a digital signal, the constant value approximately equal to an input voltage to the regulator module;
• (e) applying the digital signal to the DAC in order to develop a desired voltage drop across the regulator module;
• and
• (f) repeating steps (c)-(e) for each step interval of the phase.

An implantable medical device, comprising in combination:

• a telemetry module;
• a processor that communicates with a programmer through the telemetry module in order to configure the implantable medical device;
• a therapy module that provides a neurological stimulation waveform to a patient and receives configuration information and commands about a therapeutical treatment from the processor, the therapy module comprising:
• a waveform generator;
• and
• a waveform controller coupled to the waveform generator, the waveform controller configured to perform the steps of:
• (a) identifying a portion of a rate period interval;
• (b) partitioning the portion into a plurality of phases;
• (c) determining an approximate value of the neurological stimulation waveform during a phase;
• (d) subtracting the approximate value from a constant value in order to obtain a digital signal, the constant value approximately equal to an input voltage to a regulator module;
• and
• (e) applying the digital signal to the DAC in order to develop a desired voltage drop across the regulator module;
• and
• a power module that provides electrical power to the telemetry module, the processor, and the therapy module.