Stimulation waveforms with high- and low-frequency aspects in an implantable stimulator device
Waveforms for a stimulator device, and methods and circuitry for generating them, are disclosed having high- and low-frequency aspects. The waveforms comprise a sequence of pulses issued at a low frequency which each pulse comprising first and second charge-balanced phases. One or both of the phases comprises a plurality a monophasic sub-phase pulses issued at a high frequency in which the sub-phase pulses are separated by gaps. The current during the gaps in a phase can be zero, or can comprise a non-zero current of the same polarity as the sub-phase pulses issued during that phase. The disclosed waveforms provide benefits of high frequency stimulation such as the promotion of paresthesia free, sub-threshold stimulation, but without drawbacks inherent in using high-frequency biphasic pulses.
1 . A stimulator device system, comprising:
a user interface comprising a first input to specify a first frequency, and a second input to specify a second frequency;
control circuitry configured to issue a plurality of control signals in accordance with the first frequency and the second frequency; and
stimulation circuitry in a stimulator device configured to receive the plurality of control signals and to issue a sequence of pulses at at least one electrode node of the stimulator device, wherein each pulse has a first phase and a second phase,
wherein the first phase consists of a plurality of first monophasic sub-phase pulses of a first polarity issued at the first frequency,
wherein the second phase consists of a plurality of second monophasic sub-phase pulses of a second polarity opposite the first polarity issued at the first frequency,
wherein the pulses are issued at the second frequency.
2 . The system of claim 1 , wherein the user interface further comprises a third input to specify an amplitude.
3 . The system of claim 2 , wherein the amplitude comprises a constant current.
4 . The system of claim 2 , wherein the control circuitry is further configured to issue the plurality of control signals in accordance with the first frequency, the second frequency, and the amplitude.
5 . The system of claim 4 , wherein the amplitude sets an amplitude of the first and second monophasic sub-phase pulses.
6 . The system of claim 1 , wherein the user interface further comprises a fourth input to specify a first pulse width and a fifth input to specify a second pulse width.
7 . The system of claim 6 , wherein the control circuitry is further configured to issue the plurality of control signals in accordance with the first frequency, the second frequency, the first pulse width, and the second pulse width.
8 . The system of claim 7 , wherein the first pulse width sets a pulse width of the first and second monophasic sub-phase pulses.
9 . The system of claim 8 , wherein the second pulse width sets a duration of the first and second phases.
10 . The system of claim 1 , wherein the first and second phases are charge balanced at each at least one electrode node.
11 . A method, comprising:
receiving at a user interface a first frequency and a second frequency;
generating at control circuitry a plurality of control signals in accordance with the first frequency and the second frequency; and
providing the plurality of control signals to stimulation circuitry in a stimulator device to issue a sequence of pulses at at least one electrode node of the stimulator device, wherein each pulse has a first phase and a second phase,
wherein the first phase consists of a plurality of first monophasic sub-phase pulses of a first polarity issued at the first frequency,
wherein the second phase consists of a plurality of second monophasic sub- phase pulses of a second polarity opposite the first polarity issued at the first frequency,
wherein the pulses are issued at the second frequency.
12 . The method of claim 11 , further comprising receiving at the user interface an amplitude.
13 . The method of claim 12 , wherein the amplitude comprises a constant current.
14 . The method of claim 12 , wherein the plurality of control signals are generated at the control circuitry in accordance with the first frequency, the second frequency, and the amplitude.
15 . The method of claim 14 , wherein the amplitude sets an amplitude of the first and second monophasic sub-phase pulses.
16 . The method of claim 11 , further comprising receiving at the user interface a first pulse width and a second pulse width.
17 . The method of claim 16 , wherein the plurality of control signals are generated at the control circuitry in accordance with the first frequency, the second frequency, the first pulse width, and the second pulse width.
18 . The method of claim 17 , wherein the first pulse width sets a pulse width of the first and second monophasic sub-phase pulses.
19 . The method of claim 18 , wherein the second pulse width sets a duration of the first and second phases.
20 . The method of claim 11 , wherein the first and second phases are charge balanced at each at least one electrode node.