Functional electrical stimulator open circuit protection circuit

Abstract

The utility model provides a functional electrical stimulator open circuit protection circuit, which comprises an electrode slice J1 and a circuit body which are connected with each other, and the circuit body comprises a charging and discharging loop, a voltage division circuit, a diode D4, a reverse amplification circuit and a comparison circuit. The charging and discharging loop is connected with an electrode slice J1, the voltage division circuit is connected with the charging and discharging loop, one end of the diode D4 is connected with the voltage division circuit to filter positive voltage, the other end of the diode D4 is connected with the input end of the reverse amplification circuit, and the output end of the reverse amplification circuit is connected with the comparison circuit. The output end of the comparison circuit is used for outputting judgment information to the single-chip microcomputer. According to the embodiment, the charging and discharging loop is arranged to detect the state of the electrode plate at any time.

Description

Technical Field

[0001] The utility model relates to the technical field of rehabilitation treatment instruments, in particular to an open circuit protection circuit of a functional electrical stimulator. Background Art

[0002] It has long been known that there are electrical stimulation devices that apply electrical stimulation to nerves and muscle groups to achieve pain relief and improve muscle atrophy. The devices usually use electrodes to stick to the parts of the human body that need treatment for electrical stimulation. In actual operation, if the electrodes are not in close contact with the skin, sufficient treatment cannot be achieved. Therefore, a circuit that can detect the working status of the electrodes is urgently needed. Utility Model Content

[0003] In view of the deficiencies in the prior art, the utility model proposes an open-circuit protection circuit for a functional electrical stimulator, which can detect the working condition of the electrode piece at all times and avoid the problem of inadequate treatment caused by the electrode piece falling off.

[0004] The technical solution of the utility model is achieved in this way:

[0005] A functional electrical stimulator open circuit protection circuit comprises an electrode sheet J1 and a circuit body connected to each other, wherein the circuit body comprises a charge and discharge circuit, a voltage divider circuit, a diode D4, a reverse amplifier circuit and a comparison circuit; the charge and discharge circuit is connected to the electrode sheet J1, the voltage divider circuit is connected to the charge and discharge circuit, one end of the diode D4 is connected to the voltage divider circuit to filter out positive voltage, and the other end is connected to the input end of the reverse amplifier circuit, the output end of the reverse amplifier circuit is connected to the comparison circuit, and the output end of the comparison circuit is used to output judgment information to a single-chip microcomputer.

[0006] In a further embodiment, the charge-discharge circuit includes a resistor R26 and a capacitor C6 connected to each other, and the resistor R26 and the capacitor C6 are respectively connected to the electrode sheet J1.

[0007] In a further implementation manner, the voltage divider circuit includes a resistor R27 and a resistor R30, the resistor R27 and the resistor R30 are connected in series, and the resistor R30 is grounded.

[0008] In a further embodiment, the diode D4 is connected across the resistor R30.

[0009] In a further implementation manner, the reverse amplification circuit includes an operational amplifier U2A and a resistor R25, wherein the resistor R25 is connected to the inverting input terminal and the output terminal of the operational amplifier U2A, and the non-inverting input terminal and the reverse input terminal of the operational amplifier are respectively connected to the two ends of the diode D4.

[0010] In a further implementation manner, the comparison circuit includes a comparator U3B, the positive electrode of the comparator is connected to the reverse amplifier circuit, and the negative electrode of the comparator is connected to a VDD power supply.

[0011] In a further implementation manner, the VDD power supply is configured to be 3.3V.

[0012] In a further implementation manner, the output end of the comparison circuit is connected to a voltage-stabilizing diode D6.

[0013] Compared with the prior art, the utility model has the following advantages:

[0014] This embodiment sets up a charge and discharge circuit to constantly detect the state of the electrode sheet. When working normally, the charge and discharge circuit is in a charging state. When the electrode sheet falls off, the charge and discharge circuit discharges the circuit to generate a bipolar pulse voltage. After a series of processing by the voltage divider circuit, the diode and the reverse amplifier circuit, the voltage is compared with the comparison circuit to avoid noise influence. If it is confirmed that the electrode sheet has fallen off, the comparison circuit sends a judgment information. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] In order to more clearly illustrate the implementation methods of the utility model or the technical solutions in the prior art, the drawings required for use in the implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some implementation methods of the utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0016] Figure 1 It is a structural schematic diagram of the open circuit protection circuit of the functional electrical stimulator of the utility model. DETAILED DESCRIPTION

[0017] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments of the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0018] like Figure 1As shown, an embodiment of the utility model discloses a functional electrical stimulator open circuit protection circuit, including an electrode sheet J1 and a circuit body connected to each other, wherein the circuit body includes a charge and discharge circuit, a voltage divider circuit, a diode D4, a reverse amplifier circuit and a comparison circuit; the charge and discharge circuit is connected to the electrode sheet J1, the voltage divider circuit is connected to the charge and discharge circuit, one end of the diode D4 is connected to the voltage divider circuit to filter out the positive voltage, and the other end is connected to the input end of the reverse amplifier circuit, the output end of the reverse amplifier circuit is connected to the comparison circuit, and the output end of the comparison circuit is used to output judgment information to the single-chip microcomputer.

[0019] In a further embodiment, the charge and discharge circuit includes a resistor R26 and a capacitor C6 connected to each other, and the resistor R26 and the capacitor C6 are respectively connected to the electrode sheet J1. The voltage divider circuit includes a resistor R27 and a resistor R30, and the resistor R27 and the resistor R30 are connected in series, and the resistor R30 is grounded. The diode D4 is connected to both ends of the resistor R30. The reverse amplifier circuit includes an operational amplifier U2A and a resistor R25, and the resistor R25 is connected to the inverting input and output of the operational amplifier U2A, and the in-phase input and reverse input of the operational amplifier are respectively connected to both ends of the diode D4. The comparison circuit includes a comparator U3B, the positive electrode of the comparator is connected to the reverse amplifier circuit, and the negative electrode of the comparator is connected to the VDD power supply.

[0020] In a preferred embodiment, the VDD power supply is configured to be 3.3V.

[0021] In a preferred embodiment, the output end of the comparison circuit is connected to a voltage-stabilizing diode D6.

[0022] The working mode of the utility model is as follows: when the device is working normally, the resistor R26 and the capacitor C6 are in a charging state; when the electrode sheet is disconnected, the charging circuit is disconnected, and the resistor R26 and the capacitor C6 form a discharge circuit to discharge, generating a bipolar pulse voltage. After the voltage is divided by the resistor R27 and the resistor R30, a pulse signal with a consistent waveform but reduced amplitude is obtained; then the positive direction voltage is grounded through D4 to eliminate it, and only the negative direction voltage is retained. After the voltage is amplified by the reverse amplifier circuit, a group of positive square wave signals are output; then the signal is compared with 3.3V, and the comparator outputs a high level when it is greater than 3.3V, and a low level when it is less than 3.3V; then the voltage is stabilized to 3.3V by D6 and input into the single-chip microcomputer for judgment, and a high level is regarded as the electrode sheet falling off, and a low level is normal operation.

[0023] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A functional electrical stimulator open circuit protection circuit, comprising an electrode sheet J1 and a circuit body connected thereto, characterized in that: The circuit body includes a charge and discharge circuit, a voltage divider circuit, a diode D4, a reverse amplifier circuit and a comparison circuit; the charge and discharge circuit is connected to the electrode sheet J1, the voltage divider circuit is connected to the charge and discharge circuit, one end of the diode D4 is connected to the voltage divider circuit to filter out the positive voltage, and the other end is connected to the input end of the reverse amplifier circuit, the output end of the reverse amplifier circuit is connected to the comparison circuit, and the output end of the comparison circuit is used to output judgment information to the single-chip microcomputer.

2. The open circuit protection circuit of the functional electrical stimulator according to claim 1, characterized in that: The charge-discharge circuit includes a resistor R26 and a capacitor C6 connected to each other, and the resistor R26 and the capacitor C6 are respectively connected to the electrode sheet J1.

3. The open circuit protection circuit of the functional electrical stimulator according to claim 1, characterized in that: The voltage divider circuit includes a resistor R27 and a resistor R30. The resistor R27 and the resistor R30 are connected in series, and the resistor R30 is grounded.

4. The open circuit protection circuit of the functional electrical stimulator according to claim 3, characterized in that: The diode D4 is connected to both ends of the resistor R30.

5. The open circuit protection circuit of the functional electrical stimulator according to claim 1, characterized in that: The reverse amplification circuit includes an operational amplifier U2A and a resistor R25. The resistor R25 is connected to the inverting input terminal and the output terminal of the operational amplifier U2A. The non-inverting input terminal and the reverse input terminal of the operational amplifier U2A are respectively connected to the two ends of the diode D4.

6. The open circuit protection circuit of the functional electrical stimulator according to claim 1, characterized in that: The comparison circuit includes a comparator U3B, the positive electrode of the comparator is connected to the reverse amplifier circuit, and the negative electrode of the comparator is connected to the VDD power supply.

7. The open circuit protection circuit of the functional electrical stimulator according to claim 6, characterized in that: The VDD power supply is configured to be 3.3V.

8. The open circuit protection circuit of the functional electrical stimulator according to claim 1, characterized in that: The output end of the comparison circuit is connected to the voltage-stabilizing diode D6.

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