Leakage detection for electronic device

A method of detecting a leakage path in an electronic device includes iteratively performing operations until an iteration condition is satisfied. The operations include causing a capacitor to be set to a known state, measuring a voltage level of the capacitor, and storing data indicating the measured voltage level. The operations also include causing the capacitor to be connected to a potential leakage path, remeasuring the voltage level of the capacitor, and storing data indicating the remeasured voltage level. The operations further include comparing the measured voltage level and the remeasured voltage level to detect leakage in the potential leakage path. The iteration condition is satisfied when a difference between the measured voltage level and the remeasured voltage level satisfies a voltage threshold or when a count of iterations performed satisfies an iteration threshold.

CROSS-REFERENCE TO RELATED APPLICATION

This application is related to and claims the benefit of priority of International Application No. PCT/US2018/053623, entitled, “Leakage Detection for Electronic Device”, filed on Sep. 28, 2018, which is hereby incorporated by reference.

BACKGROUND INFORMATION

The present disclosure is related to detecting a leakage path in an electronic device.

Some electronic devices are designed for use in (or configured to be operable in) water or other conductive media. As a non-limiting example, an electronic device can include an underwater sensor that is integrated as part of an underwater wireless sensing system. The underwater wireless sensing system can be used for a variety of applications and industries. To illustrate, underwater wireless sensing system applications can include instrument monitoring applications, pollution control applications, climate recording applications, search and survey applications, marine life applications, etc.

In some scenarios, when an electronic device or system is in or exposed to a conductive medium, current leakage (e.g., a ground fault) can occur due to wiring faults or due to the conductive media entering cabling, connectors or housing of the electronic device or system. For example, there may be inadvertent contact between an energized conductor and ground caused by water entering the housing of the electronic device. If a ground fault is not detected, the ground fault can negatively impact operations of the electronic device or system. For example, the ground fault can reduce signaling reliability, sensing reliability, etc. In other scenarios, the ground fault can result in more serious defects of the electronic device, such as increased corrosion of metallic components (e.g., connectors), or device failure. Ground faults are often of concern with respect to safety—shock prevention, short circuit prevention etc. Some electronic/electrical systems are designed with isolation between portions of the system, such as in industrial equipment and machinery or vehicles like electric cars where the system is designed to provide isolation between high voltage portions of the system and low voltage or ‘chassis’ of the vehicle or equipment. Detecting faults in the isolation of these systems may be important for both safety and reliability.

SUMMARY

According to one implementation of the present disclosure, a method of detecting a leakage path in an electronic device includes iteratively, until an iteration condition is satisfied, performing operations including causing a capacitor to be set to a known state, measuring a voltage level of the capacitor, and storing data indicating the measured voltage level. The operations also include causing the capacitor to be connected to a potential leakage path, remeasuring the voltage level of the capacitor, and storing data indicating the remeasured voltage level. The operations further include comparing the measured voltage level and the remeasured voltage level to detect leakage in the potential leakage path. The iteration condition is satisfied when a difference between the measured voltage level and the remeasured voltage level satisfies a voltage threshold or when a count of iterations performed satisfies an iteration threshold.

According to another implementation of the present disclosure, an apparatus includes a circuit for testing a potential leakage path in an electronic device, where the circuit includes a capacitor. The apparatus also include a controller operable to execute firmware to iteratively, until an iteration condition is satisfied, perform operations including causing the capacitor to be set to a known state, measuring a voltage level of the capacitor, and storing data indicating the measured voltage level. The operations also include causing the capacitor to be connected to the potential leakage path, remeasuring the voltage level of the capacitor, and storing data indicating the remeasured voltage level. The operations further include comparing the measured voltage level and the remeasured voltage level to detect leakage in the potential leakage path. The iteration condition is satisfied when a difference between the measured voltage level and the remeasured voltage level satisfies a voltage threshold or when a count of iterations performed satisfies an iteration threshold.

According to another implementation of the present disclosure, a non-transitory computer-readable medium includes firmware that, when executed by a controller of an electronic device, causes the controller to iteratively, until an iteration condition is satisfied, perform operations including causing a capacitor to be set to a known state, measuring a voltage level of the capacitor, and storing data indicating the measured voltage level. The operations also include causing the capacitor to be connected to a potential leakage path, remeasuring the voltage level of the capacitor, and storing data indicating the remeasured voltage level. The operations further include comparing the measured voltage level and the remeasured voltage level to detect leakage in the potential leakage path. The iteration condition is satisfied when a difference between the measured voltage level and the remeasured voltage level satisfies a voltage threshold or when a count of iterations performed satisfies an iteration threshold.

DETAILED DESCRIPTION

Particular embodiments of the present disclosure are described below with reference to the drawings. In the description, common features are designated by common reference numbers throughout the drawings.

Particular implementations are described herein with reference to the drawings. In the description, common features are designated by common reference numbers throughout the drawings. In some drawings, multiple instances of a particular type of feature are used. Although these features are physically and/or logically distinct, the same reference number is used for each, and the different instances are distinguished by addition of a letter to the reference number. When the features as a group or a type are referred to herein (e.g., when no particular one of the features is being referenced), the reference number is used without a distinguishing letter. However, when one particular feature of multiple features of the same type is referred to herein, the reference number is used with the distinguishing letter. For example, referring toFIG.2, multiple switches are illustrated and associated with reference numbers124A,124B,124C, etc. When referring to a particular one of these switches, such as a first switch124A, a distinguishing letter “A” is used. However, when referring to any arbitrary one of these switches or to these switches as a group, the reference number124is used without a distinguishing letter.

As used herein, various terminology is used for the purpose of describing particular implementations only and is not intended to be limiting. For example, the singular forms “a,” “an,” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. Further, the terms “comprise,” “comprises,” and “comprising” are used interchangeably with “include,” “includes,” or “including.” Additionally, the term “wherein” is used interchangeably with the term “where.” As used herein, “exemplary” indicates an example, an implementation, and/or an aspect, and should not be construed as limiting or as indicating a preference or a preferred implementation. As used herein, an ordinal term (e.g., “first,” “second,” “third,” etc.) used to modify an element, such as a structure, a component, an operation, etc., does not by itself indicate any priority or order of the element with respect to another element, but rather merely distinguishes the element from another element having a same name (but for use of the ordinal term). As used herein, the term “set” refers to a grouping of one or more elements, and the term “plurality” refers to multiple elements.

As used herein, “generating”, “calculating”, “using”, “selecting”, “accessing”, and “determining” are interchangeable unless context indicates otherwise. For example, “generating”, “calculating”, or “determining” a parameter (or a signal) can refer to actively generating, calculating, or determining the parameter (or the signal) or can refer to using, selecting, or accessing the parameter (or signal) that is already generated, such as by another component or device. As used herein, “coupled” can include “communicatively coupled,” “electrically coupled,” or “physically coupled,” and can also (or alternatively) include any combinations thereof. Two devices (or components) can be coupled (e.g., communicatively coupled, electrically coupled, or physically coupled) directly or indirectly via one or more other devices, components, wires, buses, networks (e.g., a wired network, a wireless network, or a combination thereof), etc. Two devices (or components) that are electrically coupled can be included in the same device or in different devices and can be connected via electronics, one or more connectors, or inductive coupling, as illustrative, non-limiting examples. In some implementations, two devices (or components) that are communicatively coupled, such as in electrical communication, can send and receive electrical signals (digital signals or analog signals) directly or indirectly, such as via one or more wires, buses, networks, etc. As used herein, “directly coupled” is used to describe two devices that are coupled (e.g., communicatively coupled, electrically coupled, or physically coupled) without intervening components.

The techniques described herein enable detection of a leakage path (or ground fault) in circuitry of an electronic device. In a particular implementation, the electronic device includes a controller coupled to a circuit that includes a plurality of switches and a floating capacitor. The controller executes firmware to operate the circuit through a number of operational states in order to detect current leakage from a component within the electronic device to a conductive medium around the electronic device. For example, the controller can cause the capacitor to be charged then couple the charged capacitor to a potential leakage path. If the voltage level of the capacitor drops due to the capacitor being connected to the potential leakage path, this can be an indication of a ground fault (e.g., current leakage to the conductive medium). However, in some implementations, the electronic device includes other energy storage devices in addition to the capacitor. In such implementations, the voltage level in the capacitor can decrease as a result of charge carriers being transferred between the capacitor and another energy storage device. To illustrate, if the potential leakage path includes a second capacitor and the capacitor is charged to a higher voltage level than the second capacitor, charge can be transferred from the capacitor to the second capacitor when the capacitor is coupled to the potential leakage path. In this situation, a decrease in the voltage level of the capacitor due to being coupled to the potential leakage path would not be indicative of a ground fault.

To mitigate effects of this situation, the controller uses an iterative process to detect a leakage path. The iterative process includes comparing a voltage level of the capacitor when it has been set to a known state to the voltage level of the capacitor after it has been coupled to a potential leakage path. Thus, in the iterative process, the controller sets the capacitor to a known state (e.g., a specified voltage level or a discharged state). If the electronic device includes another energy storage device (e.g., a capacitor or inductor), the other energy storage device may allow current to flow to the capacitor if the known state is at a voltage level less than a voltage level of the energy storage device. To mitigate the effects of such current flow, an entire set of circuitry to be tested, including the capacitor, the other energy storage device, and other circuitry of the potential leakage path, can be discharged (or at least partially discharged) before beginning the iterative process.

FIG.1is a diagram of system100including an electronic device102with a circuit120for detecting a leakage path144(e.g., a current leakage path). In the particular implementation illustrated, the electronic device102includes, is surrounded by, or is submerged in a conductive medium140. The conductive medium140can include a component of the electronic device102, such as a chassis of the electronic device102, that is intended to be electrically isolated from electrical components of the electronic device102. Alternatively, or in addition, the conductive medium140can be part of the environment in which the electronic device102operates such as the metal chassis of a vehicle or metallic equipment in an industrial setting. For example, the electronic device102can include a floating or submersible electronic device, such as an aquatic vehicle (e.g., a manned, autonomous, or remotely piloted surface or submersible vehicle), a sensor package, etc. In such implementations, the leakage path144can be present due to a ground fault that allows current to flow from a voltage source106of the electronic device102to the conductive medium140. Thus, the circuit120and associated components of the electronic device102act as a ground fault detector to detect ground faults in the electronic device102by detecting the presence of the leakage path144.

The electronic device102includes primary circuitry150, which includes electronic components and circuitry configured to facilitate operation of the electronic device102. The specific configuration of the primary circuitry150depends on the design and functional characteristics of the electronic device102. For example, if the electronic device102is self-propelled, the primary circuitry150can include one or more motors, one or more actuators (e.g., steering actuators), etc. In various implementations, the primary circuitry150can include sensors, communications devices, control systems of the electronic device102, tools (e.g., manipulator arms, lifting devices, cargo handling devices, etc.), navigation systems, other electronic devices for sensing or changing aspects of the electronic device102, other electronic devices for sensing or interacting with an environment around the electronic device102, or a combination thereof. The configuration of the primary circuitry150can be changed from time to time, e.g., based on specific mission requirements. In some configurations, the primary circuitry150includes one or more energy storage components104, such as one or more capacitors, one or more inductors, or a combination thereof.

In the example illustrated inFIG.1, the electronic device102also includes a circuit120that includes a capacitor122and a plurality of switches124. The circuit120is coupled to one or more control nodes130of a controller108and to an input/output (I/O) node128of a processing circuit126. Although the controller108and the processing circuit126are shown inFIG.1as separate components, in some implementations, the controller108and the processing circuit126are combined in a single component, such as a microprocessor. A specific example of the circuit120, including connections to the control node(s)130and to the I/O node128, is described with reference toFIGS.2-7.

The control node(s)130are configured to control operation of the switches124(e.g., to open or close each switch) based on an operational state of the circuit120. In the particular example illustrated inFIGS.1-7, the I/O node128is configured to provide a voltage with a specified voltage level to the capacitor122when the I/O node is in an output state and is configured to measure a voltage level of the capacitor122when the I/O node is in an input state. In other implementations, the processing circuit126can include separate input and output nodes, in which case the switches124can be used to selectively couple the capacitor122to the input node or the output node.

The controller108and the processing circuit126are coupled to a memory110. In the example illustrated inFIG.1, the memory110stores firmware112(e.g., instructions), settings114, and voltage measurement data134. In other implementations, the electronic device102can include more than one memory device, in which case the firmware112, the settings114, and the voltage measurement data134can be stored in different memory devices. To illustrate, the firmware112can be stored in a non-volatile memory device, the voltage measurement data134can be stored in a volatile memory device, and the settings114can be stored in the non-volatile memory device, in the volatile memory device, or in another memory device.

In a particular implementation, the controller108can execute the firmware112to control operation of the circuit120, the processing circuit126, other components of the electronic device102, or a combination thereof. With regard to detecting the leakage path, the controller108, executing the firmware112, can control actuation of the switches124via the control node(s)130. In the example illustrated inFIG.1, the controller108can also cause the processing circuit126to selectively set the I/O node128to an input mode of operation or to an output mode of operation.

The settings114specify parameters used by the controller108to control operation of the circuit120to detect the leakage path144. For example, inFIG.1, the settings114include one or more iteration conditions132, which are described further below. In other example, the settings114can specify one or more other parameters, such as a voltage level to be output by the I/O node128when the I/O node128is in the output mode. In some implementations, the settings114can be modified or updated in response to user input138received via an I/O port136of the electronic device102. For example, the settings114can be updated to account for configuration changes in the primary circuitry150. To illustrate, in a first configuration of the primary circuitry150, the primary circuitry150may include a first set of energy storage components104or no energy storage components; whereas in a second configuration, the primary circuitry150may include a second set of energy storage components104. In this illustrative example, the settings114can be modified, via the user input138, to change operation of the controller108to account for the change in the primary circuitry150. In the illustrative example, settings114can be configurable via user input138based on a configuration of electronic device102.

During operation to detect the leakage path144, the controller108executing the firmware112can cause the capacitor122to be set to a known state. For example, the capacitor122can be at least partially discharged by coupling the capacitor122to a ground. If the primary circuitry150includes the energy storage component(s)104, the energy storage component(s)104can also be at least partially discharged so that current does not flow from the energy storage component(s)104to the capacitor122. Setting the capacitor122to a known state can also, or in the alternative, include providing a voltage with a specified voltage level to the capacitor122. To illustrate, the I/O node128can be set to an output mode and coupled (via actuation of one or more of the switches124) to the capacitor122to apply voltage to the capacitor122.

After the capacitor122is set to the known state, the processing circuit126can measure a voltage level of the capacitor122and store data indicating the voltage level in the voltage measurement data134. For example, the I/O node128can be set to an input mode and coupled (via actuation of one or more of the switches124) to the capacitor122to measure the voltage level of the capacitor122.

The capacitor122is subsequently coupled, via operation of one or more of the switches124, between a portion of the primary circuitry150and a conductive medium connection142. In this context, the portion of the primary circuitry150includes or corresponds to a potential leakage path of one of the voltage sources106to the conductive medium. The conductive medium connection142is exposed to the conductive medium140. If the leakage path144exists between a voltage source106and the conductive medium140via the potential leakage path, coupling the capacitor122to the potential leakage path of the primary circuitry150completes the circuit and enables current to flow from the capacitor122, which reduces the voltage level of the capacitor122.

After the capacitor122is coupled to the potential leakage path, the capacitor122is disconnected from the potential leakage path and the voltage level of the capacitor122is remeasured. Data indicating the remeasured voltage level is stored in the voltage measurement data134. The data indicating the voltage level after the capacitor122is set to the known state (also referred to herein as the “measured voltage level” as distinct from the remeasured voltage level) is compared to the data indicating the remeasured voltage level. As explained above, a difference between the measured voltage level and the remeasured voltage level may indicate presence of the leakage path144. However, in some implementations, such as when the primary circuitry150includes the energy storage component(s)104, the difference between the measured voltage level and the remeasured voltage level can be at least partially due to current flow from the capacitor122to the energy storage component(s)104or from the energy storage component(s)104to the capacitor122.

To reduce the effect on detecting the leakage path144of current flow between the capacitor122and the energy storage component(s)104, several of the operations described above can be iteratively repeated until one or more iteration conditions132are satisfied. For example, after at least partially discharging the capacitor122and the energy storage component(s)104, the controller108can perform an iterative process that includes setting the capacitor122to a known state, measuring the voltage level of the capacitor122, coupling the capacitor122to the potential leakage path, remeasuring the voltage level of the capacitor122, and comparing the measured voltage level and the remeasured voltage level. In a particular implementation, an iterative condition of the iteration conditions132is satisfied when the difference between the measured voltage level and the remeasured voltage level is less than or equal to the voltage threshold. In this implementation, the voltage threshold is sufficiently low such that the difference between the measured voltage level and the remeasured voltage level being less than or equal to a voltage threshold indicates that there is no significant leakage path144between the conductive medium connection142and the voltage sources106. Alternatively, or in addition, an iterative condition of the iteration conditions132is satisfied when a particular number of iterations performed satisfies an iteration count threshold. In this implementation, the iteration count reaching the iteration count threshold without any iteration resulting in the difference between the measured voltage level and the remeasured voltage level being less than or equal to a voltage threshold indicates the presence of the leakage path144. In some implementations, the controller108can generate an indication of presence (or absence) of the leakage path144. For example, the controller108can output data to a user or to another device via the I/O port136.

The number of iterations needed to reliably determine that a leakage path144is present (or absent) can vary depending on the specific configuration of the primary circuitry150, depending on the voltage sources106, or both. For example, in a first configuration, the primary circuitry150can include a relatively small-capacity energy storage component104(e.g., a small capacitor), and in a second configuration, the primary circuitry150can include a relatively large-capacity energy storage component104(e.g., a large capacitor). Assuming the capacitor122used to detect leakage is the same for each configuration of the primary circuitry150, more iterations may be needed to confirm the presence (or absence) of the leakage path144for the second configuration than for the first configuration because the capacitor122may need to be charged and discharged to the large capacitor multiple times to equalize the voltage level of the capacitor122and the large capacitor. In contrast, due to the smaller capacity of the small capacitor, the capacitor122can be charged and discharged to the small capacitor fewer times to equalize the voltage level of the capacitor122and the small capacitor.

Accordingly, the circuit120in conjunction with the controller108and the processing circuit126enables reliable detection of leakage paths (e.g., ground faults) in the electronic device102. Further, using the settings114as parameters for the firmware112to control a leakage detection process allows the circuit120to be used to detect leakage paths for a variety of configurations of the primary circuitry150of the electronic device102.

FIGS.2-7are diagrams illustrating an example of the circuit120in a various operational states. In the example illustrated inFIGS.2-7, the circuit120includes the capacitor122and the switches124, including a first switch124A, a second switch124B, a third switch124C, a fourth switch124D, a fifth switch124E, a sixth switch124F, a seventh switch124G, and an eighth switch124H. The switches124are coupled to the control nodes130, including a first control node130A, a second control node130B, a third control node130C, a fourth control node130D, a fifth control node130E, and a sixth control node130F. The control nodes130control actuation of the switches124. In the particular example illustrated inFIGS.2-7, the switches are electro-optical switches (e.g., PhotoMOS relays), each including a light emitting diode (LED) and a photo-electric element. In this example, when the LED of a particular switch124is active (e.g., outputting light) the photo-electric element of the switch124allows current flow (e.g., closes the switch124), and when the LED of a particular switch124is inactive (e.g., not outputting light) the photo-electric element of the switch124inhibits current flow (e.g., opens the switch124). In other implementations, one or more of the switches124can be an electrical switch (e.g., a transistor), an electromechanical switch (e.g., a relay), or another switch-type that is controllable by the controller108, such as a pneumatic switch.

The circuit120is coupled via the first switch124A to a first voltage source106A and via the second switch124B to a second voltage source106B. In the example illustrated inFIGS.2-7, the second voltage source106B is a ground. The circuit120is also coupled, via the third switch124C to the conductive medium connection142. The fourth switch124D, when closed, provides a resistive path to at least partially discharge the primary circuitry150, which can be coupled to the circuit120between the first switch124A and the first voltage source106A, between the second switch124B and the second voltage source106B, or both. The fifth switch124E is coupled to a first terminal of the capacitor122and to ground, such as a ground rail coupled to the second voltage source106B or another ground. The sixth switch124F is coupled to a second terminal of the capacitor122and to the ground, such as a ground rail coupled to the second voltage source106B or another ground. The seventh switch124G is coupled to the I/O node128and to the first terminal of the capacitor122. The eighth switch124H is coupled to the I/O node128and to the second terminal of the capacitor122. In the example illustrated inFIGS.2-7, the circuit120also includes a transient voltage suppressor202coupled in parallel to the capacitor122to reduce voltage spikes.

FIG.2is a diagram of an example of the circuit120in a first operational state. The first operational state illustrated inFIG.2corresponds to at least partially discharging the capacitor122and the energy storage component(s)104of the primary circuitry150ofFIG.1. In the example illustrated inFIG.2, the second switch124B, the third switch124C, and the fourth switch124D are closed in the first operational state. Further, the first switch124A, the fifth switch124E, the sixth switch124F, the seventh switch124G, and the eighth switch124H are open in the first operational state. In this state, the capacitor122and energy storage component(s)104between the circuit120and the second voltage source106B can be at least partially discharged via the resistive path provided by the fourth switch124D. In an alternative example (not specifically illustrated) of the first operational state, the first switch124A, the third switch124C, and the fourth switch124D are closed, and the second switch124B, the fifth switch124E, the sixth switch124F, the seventh switch124G, and the eighth switch124H are open. In this alternative example, the capacitor122and energy storage component(s)104between the circuit120and the first voltage source106A can be at least partially discharged via the resistive path provided by the fourth switch124D. In other words, the fourth switch124D can selectively provide a resistive discharge path.

FIG.3is a diagram of an example of the circuit120in a second operational state. The second operational state illustrated inFIG.3corresponds to at least partially discharging the capacitor122. In some implementations, the controller108controls the switches124to put the circuit120in the second operational state after the circuit has been in the first operational state for a first duration specified in the settings114. For example, as explained above, the first operational state enables at least partial discharge of the capacitor122and the energy storage component(s)104of the primary circuitry150of the electronic device102. However, in some circumstances, the capacitor122may not be fully or sufficiently discharged in the first operational state. In such circumstances, the second operational state can be used to more completely discharge the capacitor122.

In the second operational state, the first switch124A, the second switch124B, the third switch124C, and the fourth switch124D are open, and the fifth switch124E, the sixth switch124F, the seventh switch124G, and the eighth switch124H are closed. Further, the I/O node128is set to an input state, which is a high-impedance state. Accordingly, in the second operational state, both terminals of the capacitor122are coupled to ground to at least partially discharge the capacitor122.

FIG.4is a diagram of an example of the circuit120in a third operational state. The third operational state illustrated inFIG.4corresponds to setting the capacitor122to a known state. In some implementations, the controller108controls the switches124to put the circuit120in the third operational state after the circuit120has been in the second operational state for a second duration specified in the settings114.

In the third operational state, the first switch124A, the second switch124B, the third switch124C, the fourth switch124D, the sixth switch124F, and the seventh switch124G are open, and the fifth switch124E and the eighth switch124H are closed. Further, the I/O node128is set to an output state and a voltage having a voltage level specified in the settings114is applied to the I/O node128. Accordingly, energy is stored in the capacitor122responsive to the voltage applied to the I/O node128.

FIG.5is a diagram of an example of the circuit120in a fourth operational state. The fourth operational state illustrated inFIG.5corresponds to measuring a voltage level of the capacitor122. In some implementations, the controller108controls the switches124to put the circuit120in the fourth operational state after the circuit120has been in the third operational state for a third duration specified in the settings114.

In the fourth operational state, the switches124are in the same configuration as in the third operational state, and the I/O node128is set to the input state enabling the processing circuit126to measure a voltage level of the capacitor122.

FIGS.6A and6Bare diagrams of examples of the circuit120in a fifth operational state. The fifth operational state illustrated inFIGS.6A and6Bcorresponds to connecting the capacitor122to a potential leakage path. In particular, the fifth operational state ofFIG.6Acan be used to determine whether a leakage path is present between the second voltage source106B and the conductive medium140ofFIG.1, and the fifth operational state ofFIG.6Bcan be used to determine whether a leakage path is present between the first voltage source106A and the conductive medium140. In some implementations, the controller108controls the switches124to put the circuit120in the fifth operational state after the circuit120has been in the fourth operational state for a fourth duration specified in the settings114.

In the fifth operational state illustrated inFIG.6A, the second switch124B and the third switch124C are closed, and the first switch124A, the fourth switch124D, the fifth switch124E, the sixth switch124F, the seventh switch124G, and the eighth switch124H are open. In the fifth operational state illustrated inFIG.6B, the first switch124A and the third switch124C are closed, and the second switch124B, the fourth switch124D, the fifth switch124E, the sixth switch124F, the seventh switch124G, and the eighth switch124H are open.

FIG.7is a diagram of an example of the circuit120in a sixth operational state. The sixth operational state illustrated inFIG.7corresponds to remeasuring a voltage level of the capacitor122. In some implementations, the controller108controls the switches124to put the circuit120in the sixth operational state after the circuit120has been in the fifth operational state for a fifth duration specified in the settings114.

In the sixth operational state, the first switch124A, the second switch124B, the third switch124C, the fourth switch124D, the fifth switch124E, and the eighth switch124H are open, and the sixth switch124F and the seventh switch124G are closed. Further, the I/O node128is set to an input state measure the voltage level of the capacitor122

In a particular implementation, the measured voltage level of the capacitor122determined in the fourth operational state ofFIG.5and the remeasured voltage level of the capacitor determined in the sixth operational state ofFIG.7are compared to detect leakage in a potential leakage path. If a difference between the measured voltage level and the remeasured voltage level satisfies a voltage threshold (e.g., is less than or less than or equal to the voltage threshold), the controller108determines that no leakage (e.g., no ground fault) is present in the potential leakage path. In this circumstance, a testing cycle associated with the potential leakage path is complete. The testing cycle for the potential leakage path includes iteratively, until an iteration condition is satisfied, causing the capacitor122to be set to a known state, measuring a voltage level of the capacitor122(and storing data indicating the measured voltage level), causing the capacitor122to be connected to a potential leakage path, remeasuring the voltage level of the capacitor122(and storing data indicating the remeasured voltage level), and comparing the measured voltage level and the remeasured voltage level to detect leakage in the potential leakage path. In terms of the operational states illustrated inFIGS.2-7, the testing cycle includes iteratively performing operations that include at least putting the circuit120in the third operational state, putting the circuit120in the fourth operational state, putting the circuit120in the fifth operational state, and putting the circuit120in the sixth operational state. In some implementations, the operations of the testing cycle also includes putting the circuit120in the second operational state.

The iteration condition is satisfied if the difference between the measured voltage level and the remeasured voltage level satisfies the voltage threshold. However, if the difference between the measured voltage level and the remeasured voltage level fails to satisfy the voltage threshold (e.g., is greater than or greater than or equal to the voltage threshold), the controller108determines whether a count of iterations performed in the testing cycle satisfies an iteration threshold. If the count of iterations performed in the testing cycle satisfies the iteration threshold, the controller108ends the testing cycle and generates an indication that leakage is present in the potential leakage path (e.g., the controller108generates a ground fault indication). If the count of iterations performed in the testing cycle does not satisfy the iteration threshold, the controller108continues the testing cycle by performing at least one additional iteration.

In some implementations, the circuit120can be used to sequentially test multiple potential leakage paths. For example, the fifth operational state illustrated inFIG.6Acan be used for every iteration of a first testing cycle to test a first potential leakage path between the second voltage source106B and the conductive medium140. Subsequently, after determining that the first potential leakage path has a ground fault or after determining that the first potential leakage path does not have a ground fault, the controller108can test a second potential leakage path using a second testing cycle. To illustrate, the fifth operational state illustrated inFIG.6Bcan be used for every iteration of the second testing cycle to test the second potential leakage path between the first voltage source106A and the conductive medium140.

The duration of each operational state can be specified in the settings114ofFIG.1and can be modified responsive to the user input138. Additionally, or in the alternative, values of the iteration conditions132can be modified responsive to the user input138. Thus, the controller108can perform ground fault testing that is customizable to a specific configuration of the electronic device102. Accordingly, the circuit120in conjunction with the controller108and the processing circuit126enables reliable detection of leakage paths (e.g., ground faults) in the electronic device102. Further, using the settings114as parameters for the firmware112to control a leakage detection process allows the circuit120to be used to detect leakage paths for a variety of configurations of the primary circuitry150of the electronic device102.

FIG.8is a flowchart of a method800of detecting a leakage path in an electronic device. In an illustrative example, the method800can be performed by the controller108in conjunction with the circuit120. As explained below, some of the operations of the method800illustrated inFIG.8can be performed iteratively, until an iteration condition is satisfied, as part of a testing cycle. In some implementations, the method800can include other operations that are performed before the iterative operations or after the iterative operations. As a specific example, in some implementations, before performing an initial iteration of a testing cycle, the method800includes at least partially discharging a capacitor and one or more energy storage components of the electronic device102. In this example, the one or more energy storage components are distinct from the capacitor. For example, the one or more energy storage components104are components of the primary circuitry150of the electronic device102, and the capacitor122is a component of the circuit120.

InFIG.8, the testing cycle of the method800includes, at802, causing the capacitor122to be set to a known state. For example, as explained with reference toFIGS.3and4, causing the capacitor122to be set to the known state can include at least partially discharging the capacitor122and coupling the capacitor122to a voltage source associated with a specified voltage level (e.g., the I/O node128of the processing circuit126).

The method800includes, at804, measuring a voltage level of the capacitor and storing data indicating the measured voltage level. For example, as described with reference toFIG.5, the I/O node128of the processing circuit126can be set to the input mode to measure the voltage level of the capacitor122. The processing circuit126or the controller108can store data indicating the measured voltage level of the capacitor122at the memory110as an entry of the voltage measurement data134.

The method800also includes, at806, causing the capacitor to be connected to a potential leakage path. For example, the switches124of the circuit120can be configured as illustrated inFIG.6Ato connect the capacitor122to a potential leakage path between the second voltage source106B and the conductive medium140. Alternatively, the switches124of the circuit120can be configured as illustrated inFIG.6Bto connect the capacitor122to a potential leakage path between the first voltage source106A and the conductive medium140. In particular implementations, measuring the voltage level of the capacitor includes causing the capacitor to be connected to a node of a processing circuit, such as to the I/O node128of the processing circuit126. In such implementations, the method800also includes, before causing the capacitor to be connected to the potential leakage path, causing the capacitor to be disconnected from the node of the processing circuit. Disconnecting the capacitor from the processing circuit before connecting the capacitor to the potential leakage path maintains electrical isolation between the potential leakage path and the processing circuit.

The method800includes, at808, remeasuring the voltage level of the capacitor and storing data indicating the remeasured voltage level. For example, as described with reference toFIG.7, the I/O node128of the processing circuit126can be set to the input mode to measure the voltage level of the capacitor122. The processing circuit126or the controller108can store data indicating the remeasured voltage level of the capacitor122at the memory110as an entry of the voltage measurement data134. In particular implementations, remeasuring the voltage level of the capacitor includes causing the capacitor to be connected to the node of the processing circuit, such as to the I/O node128of the processing circuit126. In such implementations, the method800also includes, before remeasuring the voltage level of the capacitor, causing the capacitor to be disconnected from the potential leakage path. Disconnecting the capacitor from the potential leakage path before connecting the capacitor to the processing circuit maintains electrical isolation between the potential leakage path and the processing circuit.

The method800further includes, at810, comparing the measured voltage level and the remeasured voltage level to detect leakage in the potential leakage path. The method800also includes, at812, determining whether an iteration condition is satisfied. As an example, the iteration condition is satisfied when a difference between the measured voltage level and the remeasured voltage level satisfies a voltage threshold or when a count of iterations performed satisfies an iteration threshold. If no iteration condition is satisfied, the method800continues by performing another iteration. If an iteration condition is satisfied, the method800includes, at814, ending the testing cycle. In some implementations, the method800also includes, at816, generating a ground fault indication based on a result of the testing cycle. For example, if the testing cycle detected leakage, the controller108can send an indication, via the I/O port136, of a detected ground fault. As another example, if the testing cycle did not detected leakage, the controller108can send an indication, via the I/O port136, of no ground fault.

In some implementations, the method800also include, before performing an initial iteration of a testing cycle, receiving user input to specify a duration of one or more of the operations to be performed during the testing cycle. For example, the user input can specify a duration of one or more of the causing the capacitor to be set to the known state, the measuring the voltage level of the capacitor, the causing the capacitor to be connected to the potential leakage path, or the remeasuring the voltage level of the capacitor.

Some features of the illustrative examples are described in the following clauses. These clauses are examples of features not intended to limit other illustrative examples.

A method of detecting a leakage path in an electronic device, the method comprising:

iteratively, until an iteration condition is satisfied, performing:

causing a capacitor to be set to a known state;

measuring a voltage level of the capacitor and storing data indicating the measured voltage level;

causing the capacitor to be connected to a potential leakage path;

remeasuring the voltage level of the capacitor and storing data indicating the remeasured voltage level; and

comparing the measured voltage level and the remeasured voltage level to detect leakage in the potential leakage path,

wherein the iteration condition is satisfied when a difference between the measured voltage level and the remeasured voltage level satisfies a voltage threshold or when a count of iterations performed satisfies an iteration threshold.

The method of clause 1, wherein causing the capacitor to be set to the known state comprises at least partially discharging the capacitor and coupling the capacitor to a voltage source associated with a specified voltage level.

The method of clause 1 or clause 2, further comprising, before performing an initial iteration, at least partially discharging the capacitor and one or more energy storage components of the electronic device, the one or more energy storage components distinct from the capacitor.

The method of any one of clauses 1 to 3, wherein the electronic device includes one or more energy storage components distinct from the capacitor, and wherein, during at least one iteration, current flows from the capacitor to charge the one or more energy storage components when the capacitor is connected to the potential leakage path.

The method of any one of clauses 1 to 4, further comprising receiving user input to specify a duration of one or more of the causing the capacitor to be set to the known state, the measuring the voltage level of the capacitor, the causing the capacitor to be connected to the potential leakage path, or the remeasuring the voltage level of the capacitor.

The method of any one of clauses 1 to 5, wherein measuring the voltage level of the capacitor includes causing the capacitor to be connected to a node of a processing circuit, and further comprising, before causing the capacitor to be connected to the potential leakage path, causing the capacitor to be disconnected from the node of the processing circuit.

The method of any one of clauses 1 to 6, wherein remeasuring the voltage level of the capacitor includes causing the capacitor to be connected to the node of the processing circuit, and further comprising, before remeasuring the voltage level of the capacitor, causing the capacitor to be disconnected from the potential leakage path.

An apparatus comprising:

a circuit to test a potential leakage path in an electronic device, the circuit including a capacitor; and

a controller operable to execute firmware to iteratively, until an iteration condition is satisfied, perform operations comprising:

causing the capacitor to be set to a known state;

measuring a voltage level of the capacitor and storing data indicating the measured voltage level;

causing the capacitor to be connected to the potential leakage path;

remeasuring the voltage level of the capacitor and storing data indicating the remeasured voltage level; and

comparing the measured voltage level and the remeasured voltage level to detect leakage in the potential leakage path,

wherein the iteration condition is satisfied when a difference between the measured voltage level and the remeasured voltage level satisfies a voltage threshold or when a count of iterations performed satisfies an iteration threshold.

The apparatus of clause 8, wherein the circuit further comprises:

a first switch to selectively couple a first voltage source to the circuit;

a second switch to selectively couple a second voltage source to the circuit;

a third switch to selectively couple a conductive medium connection to the circuit;

a fourth switch to selectively provide a resistive discharge path;

a fifth switch to selectively couple a ground to the circuit;

a sixth switch to selectively couple the ground to the circuit;

a seventh switch to selectively couple the capacitor to a node of a processing circuit; and

an eighth switch to selectively couple the capacitor to the node of the processing circuit.

The apparatus of clause 9, wherein causing the capacitor to be set to the known state comprises at least partially discharging the capacitor by causing the fifth switch, the sixth switch, or both, to couple the capacitor to the ground, setting the node of the processing circuit to an input state, and causing the seventh switch, the eighth switch, or both, to couple the capacitor to the node.

The apparatus of clause 9 or clause 10, wherein causing the capacitor to be set to the known state further comprises, after at least partially discharging the capacitor, charging the capacitor by setting the node of the processing circuit to an output state and causing the seventh switch, the eighth switch, or both, to couple the capacitor to the node.

The apparatus of any one of clauses 9 to 11, wherein measuring a voltage level of the capacitor comprises causing the fifth switch, the sixth switch, or both, to couple the capacitor to the ground, setting the node of the processing circuit to an input state, and causing the seventh switch, the eighth switch, or both, to couple the capacitor to the node.

The apparatus of any one of clauses 9 to 12, wherein causing the capacitor to be connected to the potential leakage path comprises causing the first switch to couple the capacitor to the first voltage source and causing the third switch to couple the capacitor to the conductive medium connection.

The apparatus of any one of clauses 9 to 13, wherein causing the capacitor to be connected to the potential leakage path comprises causing the second switch to couple the capacitor to the second voltage source and causing the third switch to couple the capacitor to the conductive medium connection.

The apparatus of any one of clauses 9 to 14, further comprising a memory storing one or more settings, the one or more settings indicating a duration of one or more of the causing the capacitor to be set to the known state, the measuring the voltage level of the capacitor, the causing the capacitor to be connected to the potential leakage path, or the remeasuring the voltage level of the capacitor.

The apparatus of clause 15, wherein the one or more settings are configurable via user input based on a configuration of the electronic device.

The apparatus of clause 15 or clause 16, wherein the one or more setting further comprise the iteration threshold, wherein the iteration threshold is configurable via user input based on a configuration of the electronic device.

The apparatus of any one of clauses 15 to 17, wherein the one or more settings further comprise a voltage level of a voltage applied to the capacitor to cause the capacitor to be set to a known state, wherein the voltage level is configurable via user input based on a configuration of the electronic device.

The apparatus of any one of clauses 15 to 18, wherein the one or more settings further comprise the voltage threshold, wherein the voltage threshold is configurable via user input based on a configuration of the electronic device.

A non-transitory computer-readable medium comprising firmware that, when executed by a controller of an electronic device, causes the controller to iteratively, until an iteration condition is satisfied, perform operations comprising:

causing a capacitor to be set to a known state;

measuring a voltage level of the capacitor and storing data indicating the measured voltage level;

causing the capacitor to be connected to a potential leakage path;

remeasuring the voltage level of the capacitor and storing data indicating the remeasured voltage level; and

comparing the measured voltage level and the remeasured voltage level to detect leakage in the potential leakage path,

wherein the iteration condition is satisfied when a difference between the measured voltage level and the remeasured voltage level satisfies a voltage threshold or when a count of iterations performed satisfies an iteration threshold.

The illustrations of the examples described herein are intended to provide a general understanding of the structure of the various implementations. The illustrations are not intended to serve as a complete description of all of the elements and features of apparatus and systems that utilize the structures or methods described herein. Many other implementations may be apparent to those of skill in the art upon reviewing the disclosure. Other implementations may be utilized and derived from the disclosure, such that structural and logical substitutions and changes may be made without departing from the scope of the disclosure. For example, method operations may be performed in a different order than shown in the figures or one or more method operations may be omitted. Accordingly, the disclosure and the figures are to be regarded as illustrative rather than restrictive.