Management of compliance voltage for a stimulator device
A compliance voltage management algorithm is disclosed for managing the compliance voltage, VH, that powers the DAC circuitry in a stimulator device. A user can use a user interface associated with an external programming device to define a time-varying stimulation waveform to be programmed into the stimulator device. The algorithm analyzes the prescribed waveform and determines a number of groups of pulses that will be treated similarly from a VH management standpoint. Optimal compliance voltages are determined for each group, as are the rise and fall rates at which VH is able to change at transitions between groups. These rise or fall rates in VH are then used to set when the compliance voltage should increase or decrease. For example, the algorithm will automatically set VH to start rising in advance of a transition so that it is at the proper higher value when the transition occurs.
1. A method for programming a stimulator device, the stimulator device comprising a plurality of electrodes and current generation circuitry configured to provide pulses at selected ones of the electrodes, wherein the current generation circuitry is powered by a time-varying compliance voltage produced at an output of a compliance voltage generator, the method comprising:
receiving information defining a waveform comprising a sequence of pulses at the selected ones of the electrodes;
determining a plurality of groups, wherein each group comprises a plurality of contiguous pulses in the waveform;
prior to producing the waveform at the selected ones of the electrodes, associating each group with a compliance voltage variable; and
determining programming instructions configured to:
program the current generation circuitry to produce the groups thereby producing the waveform at the selected ones of the electrodes, and
program the compliance voltage generator to produce the time-varying compliance voltage at the output, wherein the compliance voltage generator is programmed with the compliance voltage variable associated with the group being produced by the current generation circuitry.
2. The method of claim 1 , further comprising determining a compliance voltage value for each compliance voltage variable, wherein each compliance voltage value is determined to be suitable to produce the pulses in their associated group at prescribed amplitudes.
3. The method of claim 2 , wherein the compliance voltage values are determined by taking measurements in the stimulator device.
4. The method of claim 1 , wherein the method further comprises use of an external device in communication with the stimulator device,
wherein the information defining the waveform is received at the external device,
wherein each group is associated with a compliance voltage variable at the external device, and
wherein the programming instructions are determined at the external device; and
further comprising transmitting the programming instructions from the external device to the stimulator device.
5. The method of claim 4 , further comprising
determining a compliance voltage value for each compliance voltage variable at the stimulator device, and
transmitting the determined compliance voltages values to the external device, wherein the programming instructions are configured to program the compliance voltage generator with the compliance voltage values to produce the time-varying compliance voltage at the output,
wherein the compliance voltage generator is programmed with the compliance voltage value associated with the group being produced by the current generation circuitry.
6. The method of claim 5 , wherein the compliance voltage values are determined by taking measurements in the stimulator device.
7. The method of claim 4 , wherein the programming instructions are further configured to cause the stimulator device to determine a compliance voltage value for each compliance voltage variable by taking measurements in the stimulator device.
8. The method of claim 1 ,
wherein the information defining the waveform is received at the stimulator device;
wherein each group is associated with a compliance voltage variable at the stimulator device, and
wherein the programming instructions are determined at the stimulator device.
9. The method of claim 8 , further comprising determining a compliance voltage value for each compliance voltage variable at the stimulator device, wherein the compliance voltage values are determined by taking measurements in the stimulator device.
10. The method of claim 1 , wherein the plurality of groups are automatically determined using a computer-implementable algorithm, wherein the computer-implementable algorithm is configured to automatically determine the plurality of contiguous pulses in each group by applying one or more rules that identify that at least some of the plurality of contiguous pulses have similar compliance voltage requirements.
11. The method of claim 10 , wherein the one or more rules identify that the plurality of contiguous pulses have amplitudes or energies that are within a specified range.
12. The method of claim 1 , wherein the method further comprises use of an external device in communication with the stimulator device, wherein at least one of the plurality of groups is determined at least in part based on input received from a user at the external device.
13. The method of claim 1 , wherein a first of the groups is produced during a time period comprising a first time period followed by a second time period, wherein the compliance voltage generator is programmed with a first of the compliance voltage variables during the first group.
14. The method of claim 13 , wherein the first compliance voltage variable is higher than a preceding compliance voltage variable, wherein the time-varying compliance voltage rises over the first time period, and wherein the time-varying compliance voltage equals the first compliance voltage variable during the second time period.
15. The method of claim 13 , wherein the first compliance voltage variable is lower than a preceding compliance voltage variable, wherein the time-varying compliance voltage falls over the first time period, and wherein the time-varying compliance voltage equals the first determined compliance voltage during the second time period.
16. The method of claim 1 , wherein the time-varying compliance voltage rises or falls over time periods when the compliance voltage variables to which the compliance voltage generator is programmed change.
17. The method of claim 1 , wherein the compliance voltage variables are determined such that the time-varying compliance voltage is always high enough to form the sequence of pulses in the waveform at prescribed amplitudes.
18. The method of claim 1 , wherein the information defining the waveform comprises a plurality of blocks of the pulses in the sequence, wherein each of the blocks comprise pulses of the same amplitude, pulse width, energy, or shape.
19. The method of claim 1 , wherein the programming instructions are further configured to program the stimulator device to make measurements to assess the time-varying compliance voltage at different points in time, wherein the stimulator device is configured to adjust values of the compliance voltage variables using the measurements.
20. The method of claim 19 , wherein if the measurements indicate during production of a particular group that the time-varying compliance voltage is too low, the stimulator device is configured to adjust the compliance voltage variable associated with that group to a higher value, and wherein if the measurements indicate during production of a particular group that the time-varying compliance voltage is too high, the stimulator device is configured to adjust the compliance voltage variable associated with that group to a lower value.