Transcutaneous nerve stimulation device using a common controller for pulse production and parameter display

• US 4,693,254 A
• Filed: 09/17/1986
• Issued: 09/15/1987
• Est. Priority Date: 06/05/1984
• Status: Expired due to Fees

• Current Assignee: Stimtech Products, Inc.
• Original Assignee: Codman & Shurtleff Incorporated (Johnson & Johnson)
• Inventors: Coombes, Alan, Mickiewicz, Stanley P.
• Primary Examiner(s): Cohen, Lee S.
• Assistant Examiner(s): SHAY, DAVID M
• Application Number:
  US06/910,271
• Time in Patent Office: 363 Days
• Field of Search: 428/419 F, 428/420, 428/420 R, 428/421, 428/422, 428/423 W
• US Class Current: 607/46
• CPC Class Codes: A61N 1/36021 for treatment of pain
• CPC Class Codes: A61N 1/3603 Control systems
• CPC Class Codes: A61N 1/37235 Aspects of the external programmer

Abstract

A transcutaneous nerve stimulation device is provided using a common controller for both output pulse production and treatment parameter display. The common controller, which preferentially takes the form of a programmed microprocessor, is connected by signal lines to both the pulse output circuitry and the display, which are controlled by time-sharing the signal lines. The controller is responsive to operator entered input signals for the calculation of output pulse characteristics and display parameters. During a majority of treatment time, the controller is providing signals on the signal lines for control of the display. The display signals are interrupted during timed intervals when output signals are produced.

Claims

1. A portable transcutaneous nerve stimulation device for producing therapeutic electrical stimulation pulses comprising:

battery means for energizing the circuitry of said device;

a microprocessor having inputs and outputs;

memory means, connected to said microprocessor, which retains a program for enabling said microprocessor to control treatment pulse production and treatment parameter display in a time-shared manner;

output pulse circuitry having an input coupled to outputs of said microprocessor and an output at which treatment pulses are produced;

a display having inputs coupled to ones of said outputs of said microprocessor and continuously responsive to signal levels at said outputs of said microprocessor for displaying treatment parameters; and

means for applying treatment parameters to an input of said microprocessor.

2. The stimulation device of claim 1, wherein said memory means retains software program means for controlling said microprocessor, partitioned into a background program means and a foreground program means,

wherein said background program means comprises means for calculating output signals for said display and for said output pulse circuitry, and wherein said foreground program means comprises means for controlling the timing of operation of said output circuitry and said display.

3. The stimulation device of claim 2, wherein said treatment parameter means includes a plurality of switches which are periodically sampled by said software program means.

4. The stimulation device of claim 3, wherein said treatment parameter means includes a mode switch which is set to control the mode of operation of said device, the setting of said mode switch being periodically sampled by said software program means.

5. The stimulation device of claim 1, wherein said output pulse circuitry includes a digital to analog converter, and wherein said display comprises a liquid crystal display;

and

wherein said microprocessor has an output bus coupled to inputs of said digital to analog converter and to inputs of said liquid crystal display.

6. The stimulation device of claim 5, wherein said microprocessor comprises means for producing control signals for said display on said output bus, said display signal production being interrupted periodically for the production of output pulse control signals on said output bus.

7. The stimulation device of claim 4, wherein said microprocessor has a data bus coupled to said mode switch and to said display, said data bus being controlled by said microprocessor as an output bus for applying control signals for said display, and as an input bus for periodically sampling the setting of said mode switch.

8. The stimulation device of claim 1, wherein said output circuitry includes a digital to analog converter having an output, a control input, and data inputs coupled to outputs of said microprocessor, and a transmission gate having an input coupled to the output of said digital to analog converter, an output coupled to an output of said device, and a control input;

said microprocessor having a first control line coupled to said control input of said digital to analog converter for causing the production of an output voltage by said converter, and a second control line coupled to said control input of said transmission gate for rendering said gate conductive during the production of a treatment pulse.

9. The stimulation device of claim 8, further including a second transmission gate having an input coupled to the output of said digital to analog converter, an output coupled to a second output of said device, and a control input;

wherein said microprocessor has a third control line, coupled to said control input of said second transmission gate, for rendering said second transmission gate conductive during the production of a treatment pulse at said second output.

10. The stimulation device of claim 8, wherein said digital to analog converter further includes a reference voltage input, wherein said microprocessor controls the application of a reference voltage to said reference voltage input during the production of treatment pulses.

11. A portable transcutaneous nerve stimulation device for producing therapeutic electrical stimulation pulses comprising:

battery means for energizing the circuitry of said device;

an output at which treatment pulses are produced;

a display for displaying parameters of said treatment pulses;

controller means having an output bus and producing control signals for said output and said display on said output bus at different times during treatment, said controller having input lines;

memory means, coupled to said controller means, for storing a program for operating said controller means for the production of treatment pulses and the display of parameters on said display;

means for coupling said display to said output bus, wherein said display is continously responsive to signals on said bus for displaying parameters in accordance with said signals;

means for coupling said output to said output bus in common with said display, wherein said output is selectively responsive to signals on said bus for the production of treatment pulses; and

means for applying treatment pulse parameter signals to said input lines of said controller means for control of said treatment pulse parameters and for display of pulse parameters on said display.

12. The stimulation device of claim 11, wherein said controller means is a digital microprocessor.

13. The stimulation device of claim 12, wherein said output bus comprises a digital bus on which output control signals and display control signals are produced in a time-shared manner by said microprocessor.

14. The stimulation device of claim 11, wherein said display comprises a liquid crystal display controlled by signals produced by said controller means;

and

wherein said output includes a digital to analog converter which is responsive to signals produced by said controller means.

15. The stimulation device of claim 14, wherein lines of said output bus are coupled to both inputs of said digital to analog converter and to segment control inputs of said liquid crystal display.

16. The stimulation device of claim 11, wherein said output includes

a digital to analog converter having an output, and an input coupled to said output bus of said controller means;

a gate having an input coupled to the output of said digital to analog converter, and an output at which treatment pulses are produced,

wherein said gate is coupled to an output line of said controller means for controllably rendering said gate conductive during the production of said treatment pulses.

17. The stimulation device of claim 11, wherein said treatment pulse parameter means comprises a plurality of switches coupled to said input lines of said controller means.

18. The stimulation device of claim 17, wherein said treatment pulse parameter means further includes a mode switch for selecting a mode of operation of said device, said mode switch being connected to an input line of said controller means.