Load-adaptive bioelectric current stimulator

• US 8,527,061 B2
• Filed: 09/01/2011
• Issued: 09/03/2013
• Est. Priority Date: 05/13/2011
• Status: Active Grant

• Current Assignee: National Chiao Tung University (Government of The Republic of China)
• Original Assignee: National Chiao Tung University (Government of The Republic of China)
• Inventors: Ker, Ming-Dou, Lin, Chun-Yu, Chen, Wei-Ling
• Primary Examiner(s): STOKLOSA, JOSEPH A
• Application Number:
  US13/224,166
• Publication Number:
  US 20120290046A1
• Time in Patent Office: 733 Days
• Field of Search: 607 1- 76
• US Class Current: 607/62
• CPC Class Codes: A61N 1/36521 the parameter being derived from measurement of an electrical impedance

Abstract

The disclosure relates to a load-adaptive bioelectrical current stimulator, which comprises a current output module, an adaptation module and a control module. The current output module generates a stimulus current to an electrode. The adaptation module detects the electrical status of the stimulus current passing through the electrode and generates a feedback signal to the control module. According to the feedback signal, the control module controls the current output module to stabilize the output status of the stimulus current adaptively. Thereby, the load-adaptive bioelectrical current stimulator can use the feedback control mechanism to regulate the value of the stimulus current to adapt to variation of load impedance.

Claims

1. A load-adaptive bioelectric current stimulator comprising:

a current output module generating a stimulus current to an electrode;

an adaptation module detecting an electric status of said stimulus current when said stimulus current passes through said electrode, and generating a feedback signal; and

a control module controlling said current output module according to said feedback signal to stabilize output of said stimulus current adaptively,

wherein said adaptation module includes;

a current mirror; and

a comparator,

wherein said current mirror of said adaptation module generates a differential signal of voltage difference to said comparator according to said stimulus current, and

wherein said comparator generates an analog current signal to said control module as said feedback signal according to said differential signal of voltage difference, and said stimulus current directs to ground through said current mirror of said adaptation module.

2. The load-adaptive bioelectric current stimulator according to claim 1, wherein said control module is a charge pump system, and according to said analog current signal, said charge pump system controls a working voltage output by said current output module in a PWM (Pulse Width Modulation) way to regulate said stimulus current.

3. The load-adaptive bioelectric current stimulator according to claim 2, wherein said current output module includes a control circuit and a current mirror of said current output module, and when said control circuit is activated, said current output module generates said stimulus current via said current mirror of said current output module.

4. A load-adaptive bioelectric current stimulator, comprising:

a current output module generating a stimulus current to an electrode;

an adaptation module detecting an electric status of said stimulus current when said stimulus current passes through said electrode, and generating a feedback signal; and

a control module controlling said current output module according to said feedback signal to stabilize output of said stimulus current adaptively,

wherein said adaptation module is an analog/digital conversion circuit, and said analog/digital conversion circuit provides a digital voltage signal for said control module as said feedback signal according to an output voltage generated by said stimulus current when said stimulus current passes through said electrode,

wherein said control module is a digital control device, and according to said digital voltage signal, said digital control device provides said current output module with an operating signal composed of a set of complementary triggering signals in a PFM (Pulse Frequency Modulation) way to regulate said stimulus current,

wherein said current output module includes a set of complementary current source circuits receiving said set of complementary triggering signals of respectively and generating said stimulus current, and said stimulus current directs to ground through said electrode, and

wherein each of said set of complementary current source circuits includes a control circuit and a current mirror, and said control circuit is turned on/off by a corresponding one of said set of complementary triggering signals.