Automatic activation of continuous glucose monitoring (CGM) transmitters

Abstract

To reduce battery discharge of a continuous glucose monitoring (CGM) transmitter.SOLUTION: For example, battery-powered electronic devices, such as continuous glucose monitoring (CGM) transmitters, have switch disconnect circuits that reduce battery discharge while the device is stored and / or in a "shelf mode". The device has two externally accessible activation pads, each configured to contact the same electrical conductor located in the packaging for the device that causes the switch disconnect circuit to disconnect the battery from the device electronics while the device is in the packaging. When the device is removed from the package, the two activation pads are no longer in contact with the conductors and the switch disconnect circuit automatically connects the battery to the device electronics. Methods and other aspects of reducing battery discharge in battery-powered electronic devices are also described.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] Related Applications This application claims the priority and benefit of U.S. Provisional Patent Application No. 62 / 901,976, filed on September 18, 2019, entitled "AUTOMATIC ACTIVATION OF CONTINUOUS MONITORING (CGM) Transmitter", which is hereby incorporated by reference in its entirety for all purposes.

[0002] The present disclosure relates to a wireless transmitter for a continuous glucose monitoring system.

Background Art

[0003] Continuous analyte detection in in vivo and / or in vitro samples, such as continuous glucose monitoring (CGM), has become routine, especially in diabetes care. By providing real-time glucose concentrations, treatment / clinical actions can be applied more timely, and glycemic status can be better controlled.

[0004] During CGM operation, the biosensor is typically inserted subcutaneously and operates continuously in an environment surrounded by tissue and interstitial fluid. The subcutaneously inserted biosensor provides a signal to a wireless CGM transmitter of the CGM sensor device, and the signal indicates the user's blood glucose level. These measurements can be automatically performed many times throughout the day (e.g., every few minutes or at other intervals).

[0005] The wireless CGM transmitter is typically attached to the outer surface of the user's skin, such as the abdomen or the posterior part of the upper arm, while the biosensor is inserted through the skin to contact the interstitial fluid.

[0006] Wireless CGM transmitters are typically battery-powered devices that may be stored and / or kept on shelves in a store or warehouse for extended periods before being used by the user. Some conventional CGM transmitters may be packaged in low-power mode, but significant battery discharge can occur during storage or shelf mode. Other conventional CGM transmitters may have an electromechanical activation switch that is initially set to disconnect the battery from the CGM electronics in order to conserve battery power during storage or shelf mode. However, such switches unfavorably increase the bulk and cost of the CGM transmitter, considering the size of the switch, and also require sealing. Furthermore, these conventional CGM transmitters rely on the user to activate the transmitter by resetting the activation switch in order to connect the battery to the CGM electronics.

[0007] Therefore, an improved wireless CGM transmitter, a method to reduce battery discharge in storage mode and / or shelf mode, and a method to start the CGM transmitter are expected. [Overview of the project]

[0008] According to a first embodiment, a method for reducing battery discharge of a continuous glucose monitoring (CGM) transmitter includes receiving a CGM transmitter in a package configured to receive and encapsulate a CGM transmitter therein; automatically electrically disconnecting the battery of the CGM transmitter from the transmitter electronics of the CGM transmitter in response to the CGM transmitter being received in the package; and automatically electrically connecting the battery to the transmitter electronics in response to the CGM transmitter being removed from the package.

[0009] According to a second embodiment, a wireless continuous glucose monitoring (CGM) transmitter includes first and second activation pads, transmitter electronic equipment, and a battery having a positive terminal and a negative terminal, the negative terminal of which is coupled to the first activation pad. The CGM transmitter also includes a switch-off circuit having an input terminal, an output terminal, and an enable terminal, the input terminal being coupled to the positive terminal of the battery, the output terminal being coupled to the power input of the transmitter electronic equipment, and the enable terminal being coupled to the second activation pad. The switch-off circuit is configured to electrically disconnect the battery from the transmitter electronic equipment in response to the electrical connection of the first activation pad to the second activation pad.

[0010] According to a third aspect, a method for reducing battery discharge in a wireless continuous glucose monitoring (CGM) transmitter includes coupling the input of a switch-off circuit to the positive terminal of a battery and coupling the output of the switch-off circuit to the power input of the transmitter electronics of the CGM transmitter. The method also includes coupling a first activation pad to the negative terminal of a battery and a second activation pad to the enable terminal of the switch-off circuit. The method further includes packaging the CGM transmitter in a package including a conductor positioned to contact both the first and second activation pads, causing the switch-off circuit to disconnect the battery from the transmitter electronics.

[0011] According to a fourth aspect, the battery-powered electronic device includes first and second activation pads, device electronic equipment, and a battery having a positive terminal and a negative terminal, the negative terminal of which is coupled to the first activation pad. The battery-powered electronic device also includes a switch-off circuit having an input terminal, an output terminal, and an enable terminal, the input terminal being coupled to the positive terminal of the battery, the output terminal being coupled to the power input of the device electronic equipment, and the enable terminal being coupled to the second activation pad. The switch-off circuit is configured to electrically disconnect the battery from the device electronic equipment in response to an electrical connection of the first activation pad to the second activation pad.

[0012] Further aspects, features, and advantages of this disclosure may be readily apparent from the following description and drawings of several exemplary embodiments and examples, including the best mode intended for carrying out the invention. This disclosure may also take other different embodiments, some of which may be modified in various ways without departing from the scope of the invention. For example, some embodiments of this disclosure are applicable to other battery-powered electronic devices provided to a user, including batteries. Such battery-powered electronic devices may include various games, music, video, communication, and / or computer devices, and / or combinations thereof. This disclosure is intended to cover all modifications, equivalents, and substitutions contained in the appended claims (see further below). [Brief explanation of the drawing]

[0013] The drawings described below are for illustrative purposes only and are not necessarily drawn to exact scale. Therefore, the drawings and descriptions should be considered illustrative and not limiting. The drawings are not intended to limit the scope of the invention in any way.

[0014] [Figure 1]Figure 1 shows a schematic diagram of a wireless sustained glucose monitoring (CGM) transmitter received in a CGM transmitter package according to one or more embodiments. [Figure 2] Figure 2A shows a bottom view of a CGM transmitter according to one or more embodiments. Figure 2B shows a side view of the CGM transmitter of Figure 2A and the CGM transmitter package (with the side panel removed) according to one or more embodiments. Figure 2C shows a side view of a CGM transmitter housed in the CGM transmitter package (with the side panel removed) of Figure 2B according to one or more embodiments. Figure 2D shows a front view of a CGM transmitter housed in the CGM transmitter package (with the front panel removed) of Figure 2C according to one or more embodiments. [Figure 3] Figure 3 shows a schematic diagram of the transmitter electronics of a CGM transmitter coupled to a CGM sensor assembly according to one or more embodiments. [Figure 4] Figure 4 shows a simplified side view of a CGM sensor device according to one or more embodiments. [Figure 5] Figure 5 shows a flowchart illustrating a method for reducing battery discharge of a CGM transmitter according to one or more embodiments. [Figure 6] Figure 6 shows a flowchart of another method for reducing battery discharge of a CGM transmitter according to one or more embodiments. [Modes for carrying out the invention]

[0015] Battery-powered electronic devices containing one or more batteries may be stored on shelves in a store or warehouse for several months before use (this may be referred to as shelf mode). These electronic devices may be exposed to significant battery discharge during shelf mode, even if they were initially set to a low-power mode. In one or more embodiments described herein, a battery-powered electronic device, which may be, for example, a wireless continuous glucose monitoring (CGM) transmitter, may include a switch-off circuit that significantly reduces battery discharge, along with packaging configured to receive and encapsulate the device while it is stored and / or in shelf mode. Furthermore, a battery-powered electronic device according to one or more embodiments described herein may automatically activate when the device is removed from its packaging.

[0016] These and other features of the battery-powered electronic devices of the present invention according to one or more embodiments are described below in relation to the wireless CGM transmitter and Figures 1-6.

[0017] Some conventional battery-powered CGM transmitters are initially packaged and configured in low-power mode. However, these CGM transmitters can still consume battery power. For example, the microcontroller in a typical low-power mode CGM transmitter can still consume 1-2 μA. After 12 months of storage or shelf mode, the battery may lose approximately 9-18 mAh. This represents enough battery power to operate a CGM transmitter for roughly two weeks. Manufacturers typically address this battery discharge problem by offering larger, more expensive batteries with sufficient power to compensate for longer storage and / or shelf mode.

[0018] Other conventional battery-powered CGM transmitters may be manufactured without an internal connection between the battery and the transmitter electronics, instead having two externally accessible conductive pads, one connected to the battery and the other to the power input of the transmitter electronics. When mounted to a CGM sensor assembly that may be positioned on the user's skin, an electrical connector on the CGM sensor assembly may contact the two conductive pads to electrically connect the battery to the transmitter electronics. However, this type of electrical connection has the disadvantage of not being sufficiently reliable for wearable devices that are subject to vibrations caused by user actions. If the electrical connection between the two conductive pads is broken (i.e., one or both of the two conductive pads lose contact with the electrical connector on the CGM sensor assembly), the CGM transmitter may lose data, even if only for a few milliseconds, and may require additional recalibration when power is restored.

[0019] Figure 1 shows a wireless CGM transmitter 100 and a CGM package 102 configured to receive a CGM transmitter 100, according to one or more embodiments. The CGM transmitter 100, while packaged in the CGM package 102, advantageously reduces battery discharge during storage and / or shelf mode and automatically starts up when removed from the CGM package 102. Advantageously, once removed from the CGM package 102, the CGM transmitter 100 requires no electrical connection by any external device, connector, or component, and is powered by its battery, requiring no other action from the user.

[0020] The CGM transmitter 100 may provide Bluetooth, WiFi, RF, or other suitable wireless communication. The CGM transmitter 100 may include at least one battery 104, a switch-off circuit 106, a transmitter electronic device 108, a first activation pad 110-A, and a second activation pad 110-B. The battery 104 may have a positive ("+") terminal and a negative ("-") terminal. The negative ("-") terminal of the battery 104 may be coupled to the first activation pad 110-A. The switch-off circuit 106 may have an input terminal 112, an output terminal 114, and an enable terminal 116, the input terminal 112 may be coupled to the positive ("+") terminal of the battery 104, the output terminal 114 may be coupled to the power input 118 of the transmitter electronic device 108, and the enable terminal 116 may be coupled to the second activation pad 110-B.

[0021] The switch-off circuit 106 may also include a transistor switch 120, a logic gate 122, an inverter 124, a differential amplifier 126 (acting as a comparator), and a current source 128. The transistor switch 120 may be coupled in series between the input terminal 112 and the output terminal 114 (i.e., in the direction of the current flow through the transistor switch 120 when turned on). The logic gate 122 may have first and second inputs and outputs, the output of which may be coupled to the control input of the transistor switch 120 to control the on / off operation of the transistor switch 120. In some embodiments, the transistor switch 120 may include a MOSFET, more specifically a P-channel MOSFET, whose drain is coupled to the input terminal 112, its source is coupled to the output terminal 114, and its gate is coupled to the output of the logic gate 122. In embodiments including a P-channel MOSFET, the logic gate 122 may include an OR gate. Other types of transistor switches and logic gates may be used as alternatives. The inverter 124 may be coupled between the enable terminal 116 and the first input of the logic gate 122. The differential amplifier 126 may have an inverting input coupled to input terminal 112, a non-inverting input coupled to output terminal 114, and an output coupled to a second input of logic gate 122. A current source 128 may be coupled between input terminal 112 and enable terminal 116. In some embodiments, the switch-off circuit 106 may include a nanopower ideal diode, such as the MAX40203 Ideal Diode from Maxim Integrated, San Jose, California.

[0022] When the second activation pad 110-B is electrically floating (i.e., the second activation pad 110-B is not electrically connected to the first activation pad 110-A, ground, or voltage), the enable terminal 116 is also electrically floating. In some embodiments, in response thereto, a current source 128 that can provide about 14 - 16 nA enables the switch-off circuit 106. That is, the inverter 124 outputs a logic LOW signal to the logic (OR) gate 122. The logic (OR) gate 122 also receives a logic LOW signal from the output of the differential amplifier 126 and outputs the logic LOW signal to the transistor (P-channel MOSFET) switch 120. The logic LOW signal received at the control input (gate) of the transistor (P-channel MOSFET) switch 120 turns it on and generates a current path between the input terminal 112 and the output terminal 114. Thereby, the battery 104 is connected to the power input 118 of the transmitter electronic device 108. In this enable mode, the voltage drop between the transistor (P-channel MOSFET) switches 120 can be less than 20 mV in some embodiments.

[0023] Connecting the second activation pad 110-B to the first activation pad 110-A connected to ground (i.e., the negative (“-”) battery terminal), for example, also grounds the enable terminal 116 and deactivates the switch-off circuit 106. That is, the inverter 124 outputs a logic HIGH signal to the logic (OR) gate 122, which continues to receive a logic LOW signal from the output of the differential amplifier 126. The logic (OR) gate 122 responds by outputting the logic HIGH signal to the control input (gate) of the transistor (P-channel MOSFET) switch 120, thereby turning off the transistor (P-channel MOSFET) switch 120. Thus, the transistor (P-channel MOSFET) switch 120 is open (i.e., there is no current path between the input terminal 112 and the output terminal 114), which disconnects the battery 104 from the power input 118 of the transmitter electronic device 108.

[0024] In this deactivation mode, in some embodiments, the self-consumption current can be about 130 nA. For example, during 12 months of storage and / or shelf mode of the CGM transmitter 100, the battery 104 can discharge by about 1.1 mAh (i.e., 130 nA × 24 hours × 365 days) during this deactivation mode. This reduced battery discharge rate advantageously matches the typical self-discharge rate of LiMn batteries.

[0025] To implement the deactivation mode while the CGM transmitter 100 is in storage mode and / or shelf mode, a CGM package 102 can be provided (e.g., by the CGM transmitter manufacturer or a packaging vendor) configured to receive and enclose the CGM transmitter 100 therein. The CGM package 102 includes a conductor 130 positioned such that when the CGM transmitter 100 is received and enclosed within the CGM package 102, a first activation pad 110-A and a second activation pad 110-B, each externally accessible on an outer surface of the CGM transmitter 100, both come into electrical contact with the conductor 130. By electrically connecting the first activation pad 110-A to the second activation pad 110-B via the conductor 130, the enable terminal 116 is grounded, which deactivates the switch-off circuit 106 as described above. The conductor 130 can be, for example, a metal plate or conductive carbon rubber and can be positioned, attached to, and / or installed within the CGM package 102 in any conventional manner (e.g., by being fitted within a molded insert positioned within the CGM package 102, by being attached or fastened, etc.). Other conductive materials can be used for the conductor 130.

[0026] Figures 2A to 2D show a CGM transmitter 200 identical or substantially similar to the CGM transmitter 100, which may have a first activation pad 210-A and a second activation pad 210-B accessible from the outside on the bottom surface 211 of the CGM transmitter 200 according to one or more embodiments. The first activation pad 210-A and the second activation pad 210-B may be coupled within the CGM transmitter 200 to operate as described above for the first activation pad 110-A and the second activation pad 110-B of the CGM transmitter 100 with respect to connecting and disconnecting one or more batteries to the transmitter electronics of the CGM transmitter 200.

[0027] Figures 2B to 2D show a CGM package 202 which may be identical to or substantially similar to the CGM package 102 and which may be configured to receive and encapsulate a CGM transmitter 200 therein according to one or more embodiments.

[0028] As shown in Figures 2B-2D, the CGM package 202 may be a conventional cardboard structure, roughly square or rectangular, or box-shaped package, having a front panel 232, a rear panel 234, a top panel 236, a bottom panel 238, and two side panels 240-A and 240-B. The CGM package 202 also includes a conductor 230 which, once the CGM transmitter 200 is received within the CGM package 202, is mounted and / or positioned or installed inside the CGM package 202 so as to make electrical contact with both the first activation pad 210-A and the second activation pad 210-B. The conductor 230 may be, for example, a metal plate, a strip of conductive carbide rubber, or any other suitable conductor. The conductor 230 may be attached to the internal surface (e.g., the internal surface of the bottom panel 238) or internal structure of the CGM package 202 in any suitable manner (e.g., via adhesive or fasteners). The CGM package 202 may further include a support surface 242 configured to receive a portion of the CGM transmitter 200 thereon. The support surface 242 may be the same cardboard structure as the panels of the CGM package 202, or alternatively, it may be, for example, a molded and / or bottom insert configured to be received inside the CGM package 202 in front of the CGM transmitter 200. Other types or structures of the support surface 242 are possible. The CGM package 202 may be configured and constructed using one or more support surfaces 242 and / or guide structures such that, for example, when the CGM transmitter 200 is fully received into the CGM package 202, the CGM transmitter 200 can be guided and received within the CGM package 202 only in an orientation in which both the first activation pad 210-A and the second activation pad 210-B are in electrical contact with the conductor 230.In other embodiments, the CGM package 202 may be of other suitable shapes, structures, and materials, provided that the CGM transmitter 200 is configured to be received and enclosed within it such that the first activation pad 210-A and the second activation pad 210-B are in electrical contact with a conductor located inside the CGM package 202, respectively.

[0029] Figure 3 shows a wireless transmitter electronics 308 of a CGM transmitter 300, which may be detachably coupled to a CGM sensor assembly 344 in one or more embodiments. Alternatively, in some embodiments, the CGM transmitter 300 and the CGM sensor assembly 344 may be an integrated unit. The CGM transmitter 300 may be identical or substantially similar to the CGM transmitters 100 and / or 200, and the transmitter electronics 308 may be identical or substantially similar to the transmitter electronics 108. The CGM sensor assembly 344 may include sensor electronics and be configured to continuously acquire glucose readings via a sensor component (not shown in Figure 3, see Figure 4) inserted into the patient's body. The CGM transmitter 300 may include contact pads 346-A, 346-B, and 346-C, respectively, which are configured to make electrical contact with the CGM sensor assembly 344, from which glucose readings are received, and those readings are transferred to the transmitter electronics 308.

[0030] The transmitter electronics 308 may include a power supply (VCC) input 318, a microcontroller 348, an antenna 350, a serial bus 352, and an analog front-end (AFE) circuit 354, and may provide Bluetooth, WiFi, RF, or other suitable wireless communication. The transmitter electronics 308 may supply power to the CGM sensor assembly 344 via power contacts 356. The analog front-end circuit 354 may process glucose readings (e.g., provide analog-to-digital signal conversion) and transfer the converted signal to the microcontroller 348 via the serial bus 352. The microcontroller 348 may be programmed to further process the converted signal to determine the glucose concentration and transfer the determined glucose concentration via the antenna 350 to a management unit or a suitable computer within range of the CGM transmitter 300.

[0031] Figure 4 illustrates a CGM sensor device 401 according to one or more embodiments. The CGM sensor device 401 includes a wireless CGM transmitter 400 which is identical or substantially similar to the CGM transmitters 100, 200, and / or 300. The CGM sensor device 401 may also include a body-mounted CGM sensor assembly 444, a sensor component 458, and a sensor pod 460. The CGM transmitter 400 may be coupled to the body-mounted CGM sensor assembly 444 in any conventional manner, and the body-mounted CGM sensor assembly 444 may be powered from one or more batteries in the CGM transmitter 400. Each of the CGM transmitters 100, 200, 300, and / or 400 may be detachable from one CGM sensor assembly and reusable in other CGM sensor assemblies. The CGM sensor assembly 444 may be identical or substantially similar to the CGM sensor assembly 344. The sensor pod 460 may be configured to receive and house the CGM sensor assembly 444 and the CGM transmitter 400, and may be mountable / attachable to the user's body 462 (e.g., torso) in any conventional manner. For example, a sensor component 458, which may be a cannula or needle, may be inserted into the user's body 462 by known means, such as the use of an insertion set. The sensor component 458 may be coupled with the CGM sensor assembly 444 to enable substantially continuous detection of blood glucose levels in the user's blood. The CGM transmitter 400 may communicate sensor readings and other data received from the CGM sensor assembly 444 to a CGM management unit or other suitable computer device (not shown) within range of the CGM transmitter 400.

[0032] Figure 5 illustrates a method 500 for reducing battery discharge in a wireless continuous glucose monitoring (CGM) transmitter, according to one or more embodiments. The method 500 may be used, for example, with a CGM transmitter 100 and a CGM package 102 and / or a CGM transmitter 200 and a CGM package 202. In process block 502, the method 500 may include receiving the CGM transmitter in a package configured to receive and encapsulate the CGM transmitter therein. For example, as shown in Figures 2B-2D, the CGM transmitter 200 may be received in a CGM package 202 configured to receive and encapsulate the CGM transmitter 200 therein.

[0033] In process block 504, method 500 may include automatically electrically disconnecting the battery of the CGM transmitter from the transmitter electronics of the CGM transmitter in response to the CGM transmitter being accepted into the package. For example, as shown in Figure 1 and above, with both the first activation pad 110-A and the second activation pad 110-B in contact with the conductor 130, the switch disconnect circuit 106 electrically disconnects the battery 104 from the transmitter electronics 108.

[0034] Furthermore, in process block 506, method 500 may include automatically electrically connecting the battery to the transmitter electronic equipment in response to the CGM transmitter being removed from the package. For example, as described above in relation to Figure 1, if the second activation pad 110-B is electrically floating (e.g., not electrically connected to the first activation pad 110-A via the conductor 130), the switch-off circuit 106 electrically connects the battery 104 to the power input 118 of the transmitter electronic equipment 108.

[0035] Figure 6 illustrates a method 600 for reducing battery discharge in a wireless continuous glucose monitoring (CGM) transmitter, according to one or more embodiments. The method 600 may be used, for example, with a CGM transmitter 100 and CGM package 102 and / or a CGM transmitter 200 and CGM package 202. In process block 602, the method 600 may include coupling the input of a switch-off circuit to the positive terminal of a battery and coupling the output of the switch-off circuit to the power input of the transmitter electronics of the CGM transmitter. Referring, for example, to Figure 1, the battery may be battery 104, the switch-off circuit may be switch-off circuit 106, and the transmitter electronics may be transmitter electronics 108.

[0036] In process block 604, method 600 may include connecting a first activation pad to the negative terminal of a battery. Referring again to Figure 1, for example, the first activation pad may be a first activation pad 110-A that can be connected to the negative ("-") terminal of battery 104.

[0037] In process block 606, the second activation pad may be connected to the enable terminal of the switch-off circuit. For example, the second activation pad 110-B may be connected to the enable terminal 116 of the switch-off circuit 106 in Figure 1.

[0038] In process block 608, method 600 may include packaging the CGM transmitter in a package that includes a conductor positioned to contact both the first and second activation pads, causing a switch-off circuit to disconnect the battery from the transmitter electronics. For example, as shown in Figure 1, the CGM transmitter 100 may be packaged in a CGM package 102 that includes a conductor 130 positioned to contact both the first activation pad 110-A and the second activation pad 110-B, thereby causing a switch-off circuit 106 to disconnect the battery 104 from the transmitter electronics 108.

[0039] In some embodiments, method 600 may also include removing the CGM transmitter from its package and automatically activating the CGM transmitter. Removing the CGM transmitter from its package causes the switch-off circuit to electrically connect the battery to the transmitter electronics in response to the conductors in the package no longer electrically connecting the first and second activation pads. As described above in relation to Figure 1, with the second activation pad 110-B electrically floating (i.e., not electrically connected to the first activation pad 110-A, ground, or voltage), the transistor switch 120 is turned on, creating a current path between the input terminal 112 and the output terminal 114, connecting the battery 104 to the power input 118 of the transmitter electronics 108.

[0040] In some embodiments, Method 600 may further include providing a package configured to house and encapsulate a CGM transmitter therein. For example, as shown in Figures 2B-2D, a CGM package 202 may be provided, configured to receive and encapsulate a CGM transmitter 200 therein.

[0041] The foregoing description discloses exemplary embodiments of the present disclosure. Modifications of the apparatus and methods of the above disclosure that fall within the scope of the present disclosure will be readily apparent to those skilled in the art. Thus, while the present disclosure is disclosed in relation to exemplary embodiments, it will be understood that other embodiments may fall within the scope of the present disclosure as defined by the following claims.

Claims

[Claim 1] A battery-powered electronic device, A battery having a positive terminal and a negative terminal, wherein the negative terminal is coupled to a first activation pad and a second activation pad, Equipment and electronic devices, A switch-off circuit having an input terminal, an output terminal, and an enable terminal, The input terminal is connected to the positive terminal of the battery, and the output terminal is connected to the power input of the device / electronic equipment, and the switch disconnection circuit is configured such that A package configured to house the aforementioned battery-powered electronic device, The package comprises a conductor, and the conductor is positioned within the package such that the first activation pad and the second activation pad each make electrical contact with the conductor while the battery-powered electronic device is received within the package, and the electrical contact between the first and second activation pads and the conductor causes the switch circuit to electrically disconnect the battery from the electronic device. A transistor switch is connected in series between the input terminal and the output terminal, A logic gate having first and second inputs and outputs, wherein the output is coupled to a transistor switch and controls the operation of the transistor switch, An inverter coupled between the enable terminal and the first input to the logic gate, A comparator having a first input connected to the input terminal, a second input connected to the output terminal, and an output connected to the second input of the logic gate, and A current source coupled between the input terminal and the enable terminal, A battery-powered electronic device equipped with the following features.

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