Battery charger circuit for battery powered implantable neurostimulation systems

• US 9,026,211 B2
• Filed: 05/09/2014
• Issued: 05/05/2015
• Est. Priority Date: 08/30/2005
• Status: Active Grant

• Current Assignee: Boston Scientific Neuromodulation Corporation (Boston Scientific Corporation)
• Original Assignee: Boston Scientific Neuromodulation Corporation (Boston Scientific Corporation)
• Inventors: Yan, Jie, He, Yuping, Peterson, David K. L., Karunasiri, Rankiri T., Chen, Joey
• Primary Examiner(s): Stice, Paula J
• Application Number:
  US14/274,442
• Publication Number:
  US 20140249603A1
• Time in Patent Office: 361 Days
• Field of Search: 607 33- 34, 607/29, 607/27, 607/39, 607/46, 607/56, 607 60- 61
• US Class Current: 607/33
• CPC Class Codes: A61N 1/36125 Details of circuitry or electric components
• CPC Class Codes: A61N 1/3787 from an external energy source
• CPC Class Codes: H02J 2310/23 The load being a medical device, a medical implant, or a life supporting device
• CPC Class Codes: H02J 50/10 using inductive coupling
• CPC Class Codes: H02J 50/20 using microwaves or radio frequency waves
• CPC Class Codes: H02J 7/0068 Battery or charger load switching, e.g. concurrent charging and load supply H02J7/0013 takes precedence
• CPC Class Codes: H02J 7/007182 in response to battery voltage
• CPC Class Codes: H02J 7/04 Regulation of charging current or voltage

Abstract

An implantable device includes a stimulation electronic circuit, a battery, a receiver configured to receive energy from a source external to the implantable stimulation device, and a battery charger circuit configured to use the energy to charge the battery and power the stimulation electronic circuit, the battery charger circuit including a load switch for connecting/disconnecting the battery, the load switch being controlled by the stimulation electronic circuit.

Claims

1. An implantable device, comprising:

a battery having a battery voltage;

a receiver configured to receive energy from a source external to the implantable device and to produce a DC voltage;

a regulator for receiving the DC voltage and configured to produce an output voltage from the DC voltage at a node, wherein the node is configured to power a load in the implantable device;

a charging circuit for receiving the DC voltage and configured to charge the battery using the DC voltage; and

a switch configured to receive the battery voltage at a first terminal, and coupled to the node at a second terminal,

wherein the switch is controllable at a third terminal to couple the battery voltage to the node.

2. The device of claim 1, further comprising a battery protection circuit, wherein the charging circuit is configured to charge the battery through the battery protection circuit.

3. The device of claim 2, wherein the switch receives the battery voltage at the first terminal through the battery protection circuit.

4. The device of claim 1, further comprising a battery protection circuit, wherein the switch receives the battery voltage at the first terminal through the battery protection circuit.

5. The device of claim 1, wherein the output voltage produced by the regulator comprises a fixed optimum operating voltage for the load.

6. The device of claim 1, wherein the charging circuit is configured to charge the battery via first and second charging paths.

7. The device of claim 6, wherein the first charging path is activated if the battery voltage is below a threshold, and wherein the second charging path is activated if the battery voltage is above a threshold.

8. The device of claim 1, wherein the charging circuit is configured to trickle charge the battery if the battery voltage is below a first threshold, and to charge the battery in a constant current mode if the battery voltage is above the first threshold.

9. The device of claim 8, wherein the charging circuit is configured to charge the battery in a constant voltage mode if the battery voltage is above a second threshold higher than the first threshold.

10. The device of claim 1, wherein the switch comprises a PMOS transistor.

11. The device of claim 10, wherein a substrate of the PMOS transistor is electrically connected to the DC voltage if the external source is providing energy to the receiver, or electrically connected to the battery voltage if the external source is not providing energy to the receiver.

12. The device of claim 1, wherein the load comprises a stimulation circuit for providing neurostimulation to a patient.

13. The device of claim 1, wherein the switch is controllable at the third terminal by the load.

14. The device of claim 1, wherein the switch is controllable at the third terminal to couple the battery voltage to the node if the external source is not present.

15. The device of claim 1, wherein the DC voltage is used by the regulator and the charging circuit to power the load and to charge the battery simultaneously.