Switching regulator for implantable spinal cord stimulation
First Claim
1. An improved switching regulator for an implantable device, wherein the switching regulator includes control circuitry, and wherein the control circuitry provides at least one control parameter for the switching regulator, the improvement comprising:
- a capacitor divider comprising at least two capacitors, and a divided voltage, wherein the divided voltage is the voltage between two of the at least two capacitors;
wherein the control circuitry provides at least one control parameter for the switching regulator based on the divided voltage.
2 Assignments
0 Petitions
Accused Products
Abstract
An improved switching regulator for implantable medical devices includes a control circuit with a capacitor divider to conserve energy, and selectable duty cycles to efficiently match the duty cycle to the charge level in a holding capacitor. The switching regulator charges the holding capacitor to commanded voltage levels, and the holding capacitor provides current for tissue stimulation. The commanded voltage level is reached by “pumping-up” the holding capacitor with the output of the switching regulator. For control purposes, the high voltage (i.e., the voltage across the holding capacitor) is divided between a fixed capacitor and a variable capacitor, and the voltage between the fixed capacitor and the variable capacitor (i.e., the divided voltage) is compared to a reference voltage. The result of the comparison is used to turn-off the switching regulator once the commanded voltage level is reached. The switching duty cycle is set to one of two values. At start-up, or when the output voltage drops below a determined threshold, a low duty cycle is used. Once the output voltage reaches the threshold, a higher duty cycle is used.
162 Citations
20 Claims
-
1. An improved switching regulator for an implantable device, wherein the switching regulator includes control circuitry, and wherein the control circuitry provides at least one control parameter for the switching regulator, the improvement comprising:
-
a capacitor divider comprising at least two capacitors, and a divided voltage, wherein the divided voltage is the voltage between two of the at least two capacitors;
wherein the control circuitry provides at least one control parameter for the switching regulator based on the divided voltage. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9)
-
-
10. An improved power supply for an implantable device, the power supply comprising:
-
a battery;
control circuitry;
a step-up switching regulator inductor with an input connected to the battery and an output connected to a node Vout;
a first switch connected between the node Vout and ground, wherein the first switch is controlled by the control circuitry;
a diode including a cathode side and an anode side, wherein the cathode side is connected to the node Vout, and the anode side is connected to a node Vh;
a holding capacitor connected between the node Vh and ground;
a second switch controlled by the control circuitry;
a first lead;
a fixed capacitor;
a node Vcd; and
a variable capacitor;
wherein the second switch, the first lead, the fixed capacitor, the node Vcd, and the variable capacitor are electrically connected in series between Vh and ground;
a third switch connected between the first lead and ground, wherein the third switch is controlled by the control circuitry;
a fourth switch connected between the node Vcd and ground, wherein the fourth switch is controlled by the control circuitry; and
a comparator having a first input connected to the node Vcd, a second input connected to a reference voltage Vref, and a comparator output provided to the control circuitry. - View Dependent Claims (11, 12, 13, 14)
-
-
15. An improved switching regulator for an implantable device, wherein the switching regulator includes a duty cycle, the improvement comprising:
-
a capacitor divider;
a divided voltage between at least two capacitors of the capacitor divider; and
two or more selectable duty cycles wherein the duty cycle is selectable from the two or more selectable duty cycles based on the divided voltage. - View Dependent Claims (16, 17)
-
-
18. A method to efficiently operate a switching regulator, comprising:
-
providing a voltage input to a switching inductor;
providing a switched path from the switching inductor to ground;
providing a second path from the switching inductor to a storage device;
measuring the voltage level of the storage device using a capacitor divider; and
controlling the switching regulator based on the voltage level. - View Dependent Claims (19, 20)
-
Specification