Voltage sensing system, method of determining abnormal circuit condition, and computer device

Abstract

A voltage sensing system, a method for determining abnormal circuit conditions, and a computer device are disclosed. The voltage sensing system for determining abnormal circuit conditions in a multilayer printed circuit board includes a printed circuit board and a controller. The printed circuit board has a plurality of layers. One of the plurality of layers includes a network of wiring and a sensing circuit. The sensing circuit includes the network of wiring and a sensing point. The sensing circuit is coupled between a voltage supply and ground. The controller is coupled to the sensing point. The controller is operable to determine a voltage at the sensing point and compare the voltage to a threshold to determine abnormal circuit conditions in the printed circuit board.

Description

Technical Field

[0001] This invention relates to monitoring the operation of printed circuit boards, and more particularly to a trace sensor for detecting short circuits between layers of a printed circuit board. Background Technology

[0002] Cellular networks require various electronic devices, such as radios and antennas, mounted on supporting structures that are typically exposed to the external environment. For example, components are often mounted on supporting structures 100 feet or more high. Therefore, these electronic devices are exposed to harsh weather conditions.

[0003] For example, 5G components may have an enclosure to house the electronic equipment. These components may include 5G Central Units (CUs), Distributed Units (DUs), Remote Radio Units (RRUs), Active Antenna Units (AAUs), and Radio Units (RUs). Typically, the enclosure houses one or more multilayer printed circuit boards (PCBs), which contain multiple electronic components such as controllers, processors, memory, and network devices. These PCBs are usually composed of insulating material and conductive traces formed on the insulating material. Unlike servers in data centers where environmental conditions are strictly controlled, 5G components are exposed to harsh environmental conditions including high temperatures, humidity, salt, sulfur dioxide exposure, rain, and direct sunlight. When systems are exposed to humid environments for extended periods, moisture and associated dissolving chemicals may seep into the enclosure, ultimately exposing the printed circuit boards to these substances.

[0004] Even indoor computer systems, such as servers in data centers, can be at risk of damage from moisture or other environmental factors due to their unfavorable indoor location. When printed circuit boards are exposed to moisture and salt, the wiring materials on the layers may undergo adverse chemical reactions. When the power supply provides a positive charge to the wiring, copper "bridges" may form between two traces on different layers. Most commonly and dangerously, copper bridges may form between power and ground traces. This can ultimately lead to a short circuit between power and ground, causing system failure and / or severe overheating / fire incidents involving components connected to the printed circuit board.

[0005] To avoid this situation, a new method is needed to remotely sense printed circuit board (PCB) faults before system malfunctions occur. Furthermore, a monitoring system is needed that can provide data to assist in PCB fault analysis. Additionally, wiring-based sensors are required to determine the likelihood of open or short circuits in multilayer PCBs. Summary of the Invention

[0006] The term "embodiment" and similar terms, such as implementation method, configuration, aspect, example, and option, are intended to refer generally to the invention and all objects claimed below. Descriptions incorporating these terms should be understood not to limit the meaning and scope of the objects described herein or the appended claims. The embodiments of the invention covered herein are defined by the appended claims, not by the content of this invention. This content provides a superior overview of various aspects of the invention and introduces concepts that will be further described in the following embodiments. This content does not identify key or essential features of the claimed objects. Nor is this content intended to solely define the scope of the claimed objects. The claimed objects should be understood by referring to appropriate portions of the entire specification, any or all of the drawings, and each claim.

[0007] According to certain aspects of the present invention, a voltage sensing system for determining abnormal circuit conditions in a multi-layer printed circuit board is disclosed. The printed circuit board has multiple layers. One of the layers includes a trace network and a sensor circuit. The sensor circuit includes the trace network and a sensing point. The sensing circuit is coupled between a voltage supply and ground. A controller is coupled to the sensing point. The controller is operable to determine the voltage at the sensing point and to compare the voltage with a threshold value to determine abnormal circuit conditions in the printed circuit board.

[0008] In other embodiments, the example voltage sensing system includes multiple sensing circuits on other layers of the printed circuit board. Each sensing circuit includes a sensing point. In another embodiment, the example voltage sensing system includes a multiplexer having multiple inputs and an output. Each input is coupled to one of the multiple sensing points. The output is coupled to a controller. The controller is operable to select one of the multiple sensing points. In another embodiment, the circuit board is a motherboard, and the controller is a baseboard management controller (BMC). In another embodiment, the sensing circuit includes a first resistor coupled to a voltage supply and a wiring network. A second resistor is coupled to the wiring network and the sensing point. A third resistor is coupled between ground and the sensing point. The first, second, and third resistors are multiple trace segments formed near multiple edges of the layers. In another embodiment, the threshold is a predetermined value. In another embodiment, the threshold is determined by an initial value of the sensing point, which is measured when the printed circuit board is initially powered. In another embodiment, it is determined that the voltage at the sensing point occurs periodically. In another embodiment, the abnormal circuit condition is a short circuit between the wiring network and another layer, and the sensed voltage exceeds a threshold. In another embodiment, the abnormal circuit condition is an open circuit in the wiring network, and the sensed voltage is below a voltage threshold.

[0009] Another disclosed example is a method for identifying abnormal circuit conditions in a multilayer printed circuit board. A supply voltage is provided to a sensing circuit on one of the multiple layers of the printed circuit board; the sensing circuit is contained within a wiring network on that layer. The voltage value at the sensing point of the sensing circuit is determined. The voltage value at the sensing point is compared to a voltage threshold. Based on the comparison result, it is determined whether an abnormal circuit condition exists.

[0010] In other embodiments of the example method, the printed circuit board includes multiple sensing circuits on other multiple layers. Each of the multiple sensing circuits includes a sensing point. In another embodiment, the printed circuit board is a motherboard, and the controller is a substrate management controller. In another embodiment, the sensing circuit includes a first resistor coupled to a supply voltage and a wiring network. A second resistor is coupled to the wiring network and the sensing point. A third resistor is coupled between ground and the sensing point. The first, second, and third resistors are multiple wiring segments formed near multiple edges of the layers. In another embodiment, the voltage threshold is a predetermined value. In another embodiment, the voltage threshold is determined by an initial value of the sensing point, which is measured when the printed circuit board is initially powered. In another embodiment, determining the voltage value of the sensing point occurs periodically. In another embodiment, an abnormal circuit condition is a short circuit between the sensing point and the wiring network of another layer, and the sensed voltage exceeds the voltage threshold. In another embodiment, an abnormal circuit condition is an open circuit in the wiring network, and the sensed voltage is below the voltage threshold.

[0011] Another disclosed example is a computer device having a supply voltage source and a circuit board having multiple layers. Each of the multiple layers has a wiring network. At least one of the multiple layers includes sensing circuitry having a wiring network, sensing points, and multiple wiring segments located near multiple edges of the layer to form a circuit between the supply voltage source and ground. The device has a substrate management controller coupled to the sensing points. The substrate management controller reads the voltage at the sensing points and compares the voltage with a threshold voltage to determine abnormal circuit conditions in the circuit board.

[0012] The foregoing summary does not cover every embodiment or aspect of the invention. Rather, the foregoing summary provides only examples of some novel aspects and features described herein. These features and benefits, as well as other features and benefits of the invention, will readily become apparent from the following detailed description of several representative embodiments and methods of carrying out the invention, accompanied by numerous accompanying drawings and the appended claims. Further aspects of the invention will be apparent to those skilled in the art from the detailed description of various embodiments, accompanied by the accompanying drawings and the brief description thereof. Attached Figure Description

[0013] The invention and its benefits, along with the accompanying drawings, will be better understood through the following description of several representative embodiments, with reference to the accompanying drawings. These drawings depict only several representative embodiments and should not be construed as limiting the scope of the various embodiments or claims.

[0014] Figure 1 A perspective view of a 5G component having an example printed circuit board and a voltage wiring sensor, for certain aspects of the present invention;

[0015] Figure 2 For certain aspects of the present invention Figure 1 Side perspective view of each layer of the printed circuit board of 5G components;

[0016] Figure 3 This is a circuit diagram of a wiring sensor and monitoring system on different layers of a printed circuit board, representing certain aspects of the present invention.

[0017] Figure 4 For certain aspects of the present invention detected Figure 2 A circuit diagram showing a short circuit between two layers of a printed circuit board;

[0018] Figure 5 A circuit diagram for detecting an open circuit on a single wiring layer of a printed circuit board, according to certain aspects of the present invention.

[0019] Figure 6 For certain aspects of the present invention and Figure 1 A schematic diagram of the wiring sensor locations used in an exemplary 5G component with an exemplary hard disk backplane (HDD backplane); and

[0020] Figure 7 This is a flowchart of a program (routine) executed by a controller for certain aspects of the present invention to determine whether a printed circuit board may fail due to abnormal circuit conditions.

[0021] Symbol Explanation

[0022] 100, 122: Components

[0023] 110: Shell

[0024] 120, 140, 142, 144: Circuit Boards

[0025] 130: Cable Port

[0026] 150: Baseboard Management Controller

[0027] 210,212,214,216,218,220,222,224: Layers

[0028] 230, 232, 234, 236, 238, 240, 242, 244: Cabling network

[0029] 250: Voltage Channel

[0030] 252: Grounding Channel

[0031] 300, 302: Sensing circuit

[0032] 310, 312, 314: Resistors

[0033] 320: Voltage source

[0034] 322: Grounding wire

[0035] 330, 332, 334, 336: Sensing points

[0036] 340: Multiplexer

[0037] 342: Input terminal

[0038] 346: Select Line

[0039] 348: Signal line

[0040] 400: Bridge

[0041] 402: Resistor

[0042] 510: Opening section

[0043] 610, 612, 614, 616, 618: Pores

[0044] 630, 632, 634, 636, 638: Sensors

[0045] 710,712,714,716,718,720,722,724,726,728,730: Steps Detailed Implementation

[0046] Various embodiments are described below with reference to the accompanying drawings, wherein the same element symbols used in multiple figures denote similar or equivalent elements. The drawings are not necessarily drawn to scale and are provided only to illustrate various aspects and features of the invention. This specification sets forth numerous specific details, relationships, and methods to provide a comprehensive understanding of certain aspects and features of the invention; however, those skilled in the art will understand that these aspects and features can be practiced without one or more specific details, or with other relationships or other methods. In some cases, well-known structures or operations are not shown in detail for illustrative purposes. The various embodiments disclosed herein are not necessarily limited to the described sequence of actions or events, as some actions may occur in a different order and / or simultaneously with other actions or events. Furthermore, not all described actions or events are necessary to realize certain aspects and features of the invention.

[0047] For the purposes of this embodiment, unless otherwise stated and where appropriate, the singular form includes the plural form and vice versa. The word "comprising" means "including but not limited to". Furthermore, words indicating rough estimates, such as "about", "almost", "approximately", "around", etc., may be used here, for example, to mean "on that value", "close to that value", or "almost on that value", or "within 3-5% of that value", or "within acceptable manufacturing tolerances", or any logical combination thereof. Similarly, the terms "vertical" or "horizontal" additionally include "within 3-5% of" the vertical or horizontal direction, respectively. Furthermore, words describing direction, such as "top", "bottom", "left", "right", "above", and "below", represent directions related to the equivalent directions described in the accompanying drawings; as understood from the context of the referenced object or element, such as from its common location; or as stated herein.

[0048] This invention relates to forming multiple traces at the edges of certain layers of a multilayer printed circuit board (PCB) for sensing voltage. These edge traces can serve as part of a voltage sensing circuit that can detect the possibility of an abnormal circuit condition, such as a short circuit between multiple layers of the PCB or an open circuit in the wiring network of one of the multiple layers. The edge traces are configured to provide measurable sensing voltage points. Certain threshold voltages can be measured corresponding to different degrees of degradation of the multiple traces. Based on multiple measurements, by comparing the measured sensing voltage with the threshold voltage, abnormal circuit conditions can be detected. Depending on the severity of the condition, a response ranging from issuing an alert to shutting down components can be made.

[0049] Figure 1 This is an exploded perspective view illustrating a 5G component 100, which in this example is a basestation unit. Component 100 includes an outer housing 110 designed to withstand environmental factors such as rainfall, extreme cold, or extreme heat. The housing 110 is mounted to protect a multilayer printed circuit board 120. Various components 122 are mounted on the printed circuit board 120. The housing 110 also includes multiple cable ports 130, through which external connections can be made to the various components 122 on the printed circuit board 120. The cable inlets of the cable ports 130 also allow moisture and other environmental conditions to enter the interior of the housing 110.

[0050] In this example, printed circuit board 120 is a motherboard containing multiple processors, storage devices, interface circuits, and a management controller, such as a baseboard management controller 150. Component 100 may include circuit boards 140, 142, and 144, which may have different components to provide additional functionality to component 100. For example, in this example, circuit boards 140, 142, and 144 may have storage devices, network interfaces, or processors. The baseboard management controller 150 on printed circuit board 120 can collect voltage sensing data from circuit boards 120, 140, 142, and 144. In this example, circuit board 140 is a hard drive backplane containing multiple attached hard drives. Circuit boards 142 and 144 are expansion cards with additional components.

[0051] Voltage sensing data can determine whether abnormal circuit conditions, such as short circuits or open circuits, have occurred or may occur on circuit boards 120, 140, 142, and 144. As will be described, if any circuit board 120, 140, 142, or 144 is close to failure due to an abnormal circuit condition, the board management controller 150 can be programmed to take actions such as issuing an alert, shutting down a specific circuit board, or shutting down the entire component 100 to prevent failure.

[0052] Figure 2 Draw Figure 1 An exploded perspective view of multiple layers of a printed circuit board 120. In this example, the printed circuit board 120 comprises different layers 210, 212, 214, 216, 218, 220, 222, and 224. Each layer 210, 212, 214, 216, 218, 220, 222, and 224 is made of an insulating material, such as reinforced glass fiber with epoxy resin. Conductive wiring networks 230, 232, 234, 236, 238, 240, 242, and 244 are formed on each corresponding layer 210, 212, 214, 216, 218, 220, 222, and 224. Interconnecting conductive wiring is also formed between the wiring networks 230, 232, 234, 236, 238, 240, 242, and 244 of each layer.

[0053] Component 100 includes a power supply unit connected to an external power source. The power supply unit is connected to a voltage regulator on circuit board 120. The voltage regulator provides supply voltage to different voltage rails 250, which are accessible via wiring networks 230, 232, 234, 236, 238, 240, 242, and 244. An additional set of ground rails 252 completes the circuit; this set of ground rails is also accessible via wiring networks 230, 232, 234, 236, 238, 240, 242, and 244.

[0054] Figure 3 Showing the use of Figure 2 An example voltage sensing circuit 300 is shown for a printed circuit board 120. The printed circuit board 120, as shown in Figures 1-2, includes a series of layers 210, 212, 214, 216, 218, 220, 222, and 224 having wiring networks 230, 232, 234, 236, 238, 240, 242, and 244. Four layers 212, 216, 220, and 224 have sensing circuitry formed by multiple wiring segments from their respective wiring networks 232, 236, 240, and 244. In this example, the wiring networks 232, 236, 240, and 244 have multiple wirings located near the edges of their respective layers, which serve as elements of the voltage sensing circuitry.

[0055] The plurality of wirings forming the sensing circuit 300 include those made of Figures 2-3 The portions represented by resistors 310, 312, and 314. Therefore, the different wiring segments represented by resistors 310, 312, and 314, combined... Figure 2 The wiring network 232 on layer 212 forms Figure 3 The sensing circuit 300 is shown. The voltage sensing circuit 300 is coupled to a voltage supply or voltage source 320 (Vcc) supplied by one of a plurality of voltage channels 250. The voltage supply 320 is coupled to a wiring segment represented by a first resistor 310 (R1), which connects to a wiring network 232. A second resistor 312 (R2) is a wiring segment and is connected in series with the wiring network 232 of layer 212. A sensing point 330 is formed at the other end of the second resistor 312. The sensing point 330 is located between the second resistor 312 and a wiring segment forming a third resistor 314. The other end of the third resistor 314 is coupled to a ground lead 322, which is one of a plurality of ground channels 252. Figure 2 As shown, the multiple wiring segments forming resistors 312 and 314 are preferably configured in the space near the edge of layer 212, which cannot be used for other circuits.

[0056] In this example, each of the four layers 212, 216, 220, and 224 has corresponding sensing points 330, 332, 334, and 336, which are part of multiple sensing circuits. The multiple sensing circuits in layers 216, 220, and 224 are identical to sensing circuit 300 because each sensing circuit has three resistors integrated with a wiring network. Other sensing circuits similar to sensing circuit 300 can also be formed on other parts of the layers, for example... Figure 2 The sensing circuit 302 shown is shown.

[0057] Sensing points 330, 332, 334, and 336 are coupled to multiple inputs of multiplexer 340. The output of multiplexer 340 is coupled to A / D input 342 of a programmable controller, such as board management controller 150. Board management controller 150 is coupled to select line 346, which allows board management controller 150 to select an input of multiplexer 340. In this example, board management controller 150 periodically senses the voltage at each sensing point 330, 332, 334, and 336 to determine whether a short circuit or open circuit has begun to occur on any layer of printed circuit board 120. In this example, board management controller 150 stores the sensed data in a storage device such as flash memory. During the preparation of components on board 120, multiple components of board 120 may initially be powered. Next, the board management controller 150 stores multiple baseline voltage measurements obtained from sensing points 330, 332, 334, and 336 in a storage device. During normal operation of the circuit board 120, the board management controller 150 can execute firmware to analyze the relationship between the received sensed voltage data and the baseline voltage measurements. Based on the analysis results, the board management controller 150 can determine potential or actual short circuits or open circuits on the printed circuit board 120. The board management controller 150 can send alerts, determine the severity of the situation, and perform other multilayer diagnostic functions related to the circuit board 120. In this example, other programmable devices (e.g., processors, field-programmable gate arrays (FPGAs), complex programmable logic devices (CPLDs), etc.) or hardwired devices (e.g., application-specific integrated circuits (ASICs), etc.) can perform the voltage sensing and analysis functions of the board management controller 150.

[0058] Power supply voltage source 320 (Vcc) supplies power to each sensing circuit for a layer, such as sensing circuit 300 for layer 212, through a resistor network formed by wiring network 232, resistors 310, 312, 314, and ground (e.g., ground wire 322). In this example, the power supply voltage of voltage source 320 can be a standard level, such as 12V, or optionally 24V or 48V for specialized applications such as 5G components. A charge pump can be used to boost the standard voltage level to obtain a higher voltage level. The differential voltage (V-diff) between two adjacent wirings on two adjacent layers is:

[0059] V-diff=Vcc×R1 / (R1+R2+R3)

[0060] The voltage from the voltage supply carried by the wiring network (e.g., wiring network 232) generates an electric field between the wiring layers, which in turn induces copper crystallization and / or corrosion when moisture or water vapor penetrates multiple layers of the contact printed circuit board. This crystallization and corrosion in the wiring layers has the effect of adjusting the R1 value, which in turn affects the V-diff value. The V-diff value accelerates / decelerates this effect, resulting in a change in the sensitivity of R1. Therefore, bringing the wiring closer together increases sensitivity, while separating the wiring decreases sensitivity.

[0061] Multiple sensing points, such as sensing point 330 (S1), are connected to the A / D converter input 342 of the substrate management controller 150 via multiple inputs of multiplexer 340. Multiplexer 340 may also have multiple inputs coupled to multiple sensors from other printed circuit boards or multiple printed circuit boards in component 100. Thus, in addition to printed circuit board 120, substrate management controller 150 can monitor other printed circuit boards. Alternatively, when using only a single voltage sensing circuit, the voltage sensing circuit can be directly connected to A / D input 342. Instead of using multiplexer 340, substrate management controller 150 may have other multiple inputs coupled to multiple different sensing points, such as GPIO inputs. Alternatively, substrate management controller 150 may use a more complex I2C A / D expander to manage multiple sensors.

[0062] The sensed voltage at each sensing point (e.g., sensing point 330) can be expressed as:

[0063] V(s1)=Vcc×R3 / (R1+R2+R3)

[0064] The sensed voltage can be compared with the aforementioned sensed voltage readings, such as a baseline sensed voltage reading or a threshold voltage, to determine whether an abnormal circuit condition may have occurred. For example, changes in certain sensed voltages indicate a change in the R1 value, which may indicate the possibility of a short circuit or open circuit between multiple traces. By monitoring the voltage at a sense point (e.g., sense point 330V(s1)), the example system can detect potential open circuit or short circuit faults in multiple layers of printed circuit board 120.

[0065] Figure 4 The diagram illustrates a short-circuit scenario between wiring networks on adjacent layers of the printed circuit board 120. Figure 4 middle, and Figure 3 Similar components and Figure 3 The corresponding components are represented by the same component symbols. As described here, short circuits can occur between adjacent layers because the wiring networks of adjacent layers are very close to each other. Therefore, the corrosive effect of moisture and the interaction of electric fields generated in the wiring networks can induce short circuits between the wiring networks of two stacked layers. Figure 4 In the example shown, a short-circuit bridge 400, formed by the conductive material of wiring networks 230 and 232, is formed between wiring network 230 of layer 210 and wiring network 232 of layer 212. As described above, the short-circuit bridge 400 may be caused by the interaction of an electric field and water vapor, which leads to the formation of the bridge 400 between wiring networks 230 and 232. The short-circuit bridge 400 is represented by resistor 402 (Rs). When the short-circuit bridge 400 is formed, the voltage from voltage source 320 is directly transmitted from wiring network 230 to wiring network 232 of layer 210 through the short-circuit bridge 400. Therefore, the voltage is bypassed to the first resistor 310 through the short-circuit bridge 400. As the bridge 400 conducts more voltage, the effect of the first resistor 310 weakens, thereby increasing the voltage sensed at voltage sensing point 330. In a full short circuit, the first resistor 310 (R1) has an infinite value, and the sensed voltage drops to the voltage drop across the second resistor 312 (R2).

[0066] Therefore, in the following equation, Rs represents the short-circuit resistance 402.

[0067] V(s1)=Vcc×R3 / (R2+Rs||R1)

[0068] In this equation, the value of Rs is inversely proportional to the severity of the short-circuit bridge 400. Therefore, when the short-circuit bridge 400 is initially formed, the value of Rs is high, but as the size of the bridge 400 increases, the resistance value of resistor 402 (Rs) decreases. Therefore, when the short-circuit bridge 400 begins to form, the voltage V(s1) at sensing point 330 will increase (compared to the initial value of V(s1) when there is no short circuit). As more conductive material forms the bridge 400, worsening the short circuit, the voltage (V(s1)) at sensing point 330 will increase. Since R1 is actually short-circuited and not in the sensing circuit, the maximum value of V(s1) can be expressed as Vcc × R3 / (R2 + R3).

[0069] Short circuits caused by moisture-induced bridging typically do not occur on a specific layer because the distance between multiple wires in an individual wiring network is closer than the distance between layers. However, moisture-induced erosion can cause open circuits in wiring networks on a single layer's horizontal plane. Such open circuits can also be detected by the example sensing system.

[0070] Figure 5 Draw an open-circuit scenario route diagram of a cabling network on one layer of a multi-layer structure, taking cabling network 232 of layer 212 as an example. Figure 5 middle, and Figure 3 Similar components and Figure 3 The corresponding component is represented by the same component symbol. In this example, the open circuit 510 is caused by erosion leading to damage to the wiring on the wiring network 232. The open circuit 510 can be represented by a resistor Ro. Therefore, in this scenario, the equation for the voltage at sensing point 330 is:

[0071] V(s1)=Vcc×R3 / (R2+Ro+R1)

[0072] The resistance Ro of the open circuit 510 is proportional to the severity of the open circuit. When the wiring begins to thin due to erosion, resulting in an open circuit, the voltage V(s1) at the sensing point 330 will decrease (compared to the initial value of V(s1)). When the wiring is completely broken, the voltage V(s1) at the sensing point 330 will be 0V, indicating complete damage to the circuit.

[0073] In this example, multiple sensing circuits, such as sensing circuit 300, are formed only on every other layer of the printed circuit board 120. Therefore, in this example, open circuits may only be detected on four out of eight layers. However, if complete open circuit detection is desired on every layer of the printed circuit board 120, similar sensing circuits formed on the wiring network can be mounted on every other layer.

[0074] like Figure 3As shown, the substrate management controller 150 can also connect to multiple sensing points on other circuit boards, such as the sensing points on circuit board 140. In this example, circuit board 140 has eight layers. Each of four of the eight layers has similar sensing circuitry, which is formed by multiple wiring segments located at the edges of the layers and a wiring network on the layers. Each of the multiple sensing circuits on circuit board 140 has a sensing point, and each sensing point is connected to multiple other inputs of multiplexer 340 via signal line 348. Thus, the substrate management controller 150 can select the voltage inputs from multiple sensing points on circuit board 120 or circuit board 140, or other circuit boards for the component, via the select line 346 connected to multiplexer 340. In this way, the substrate management controller 150 can monitor the short-circuit and open-circuit conditions of all circuit boards of a specific component.

[0075] When the board management controller 150 detects a potential abnormal circuit condition, such as a short circuit between layers or an open circuit in one layer of the board, the board management controller 150 can be programmed to perform a series of actions. These actions may include recording the potential condition in the error log, sending an alert, shutting down the entire system, managing the power controller, shutting down the power supply to a specific board, sending a command to the host operating system (OS) to stop some circuitry, and sending a command to shut down an entire component. The board management controller 150 can determine which action to perform based on the severity of the condition.

[0076] The wiring that makes up the sensing circuit can also be placed near areas prone to failure. For example, during some printed circuit board manufacturing processes, certain areas of the printed circuit board may be susceptible to microcracks due to the formation of vias or other shaping requirements. Since moisture-induced degradation may begin near these cracks, these areas may be ideal locations for placing sensing wiring. Furthermore, there may be multiple sensing points located in different regions of a layer, and these sensing points can be selected based on various factors, such as manufacturing data indicating susceptibility to cracking.

[0077] Sensing wiring can be placed horizontally on the same layer or vertically on different layers. Sensing wiring can be placed in the keep-out zone of a layer, such as near the edge to preserve the layout real estate, in order to improve sensing performance against expected degradation.

[0078] Figure 6 The illustration can be used as Figure 1The layout of the printed circuit board 140 for the hard drive backplane. The printed circuit board 140 has multiple large apertures 610, 612, 614, 616, and 618 to accommodate the hard drive or other components. The formation of apertures 610, 612, 614, 616, and 618 in the printed circuit board 140 creates interface areas prone to microcracks and thus moisture ingress. Therefore, different sensing wiring can be fabricated in multiple strategic locations, such as near the edges of apertures 610, 612, 614, 616, and 618, to enable the sensing system to detect short circuits or open circuits.

[0079] In this example, sensor 630 is placed near the edge of circuit board 140 and in a space where circuit wiring is prohibited. Sensor 630 is similar to... Figure 3 The sensing wiring is shown. Thus, the sensing system can detect short circuits between two layers of the multiple layers of the circuit board 600 through the sensor 630.

[0080] Other sensors are placed near the edges of apertures 610, 612, 614, 616, and 618. The cut areas around apertures 610, 612, 614, 616, and 618 are prone to microcracks, making them a good location for sensor placement. Therefore, additional sensors, such as sensors 632, 634, and 636, are placed near the vertical edges of apertures 610, 612, and 618. Alternatively, sensors, such as sensor 638, can be placed around the horizontal edge of aperture 614. These additional sensors allow for the scaling and / or enhancement of the detection and diagnostic algorithms executed by the board management controller 150 or other management controllers.

[0081] Figure 7 For can be Figure 3 Flowchart of the detection and diagnostic procedures executed by the baseboard management controller 150. Figure 7The program is a representative example of machine-readable instructions for reading voltage values ​​from a sensing circuit to determine whether an open or short circuit is present. In this example, the machine-readable instructions contain an algorithm executed by (a) a processor; (b) a controller; and / or (c) one or more other suitable processing devices. The algorithm may be contained in software stored on tangible media, such as flash memory, CD-ROM, floppy disk, hard disk, digital video (DVD) disc, or other storage devices. However, those skilled in the art will readily understand that the entire algorithm and / or parts of the algorithm may optionally be executed by a device other than a processor and / or contained in firmware or dedicated hardware in a known manner (e.g., implemented by an application-specific integrated circuit (ASIC), a programmable logic device (PLD), a field-programmable logic device (FPLD), a field-programmable gate array (FPGA), a discrete logic device, etc.). For example, any or all parts of the program may be implemented by software, hardware, and / or firmware. Furthermore, some or all of the machine-readable instructions described in the flowchart may be manually executed. Additionally, although an example program has been described herein, those skilled in the art will readily understand that many other methods can be used to implement the example machine-readable instructions.

[0082] Figure 7 The detection and diagnostic procedures can be executed periodically by the substrate management controller 150, for example, once a day, to determine whether there are signs of short circuits or open circuits in multiple layers of the printed circuit board. The detection and diagnostic procedures can be used to monitor the network of wiring sensors on different layers and locations of the printed circuit board, as well as multiple printed circuit boards in the computing device managed by the substrate management controller.

[0083] In this example, a register or memory accessible by the board management controller 150 contains baseline voltage readings for the sensing points. Initial voltage readings are acquired during component preparation, and these initial voltage readings indicate the expected voltages assuming multiple wiring networks across multiple layers of the board are functioning correctly. In this example, baseline voltage readings for all sensing points are stored in flash memory.

[0084] The substrate management controller 150 obtains voltage readings from sensing points, for example from... Figure 3The sensing point 330 acquires a voltage reading (step 710). The substrate management controller 150 determines whether the voltage is lower than a baseline voltage value (step 712). If the sensed voltage is lower than the baseline value, the substrate management controller 150 then compares the sensed voltage with a low threshold value, which indicates that the wiring network may be open (step 714). If the voltage is lower than the low threshold value (step 714), the substrate management controller 150 will send a warning signal indicating a potential open circuit in the wiring network (step 716).

[0085] Next, the program compares the sensed voltage reading with a first high threshold (step 718). If the voltage is not lower than the baseline value or the lower threshold, the voltage reading is then compared with the first high threshold (step 718). If the sensed voltage exceeds the first high threshold (step 718), the board management controller 150 will shut down the board because a short circuit has occurred between layers (step 720). If the voltage is lower than the first high threshold, the board management controller 150 compares the sensed voltage reading with the second high threshold and determines whether the sensed voltage reading exceeds the second high threshold (step 722). If the voltage exceeds the second high threshold (step 722), the board management controller 150 will send an impending fault warning to the remote monitoring station (step 724). If the voltage is lower than the second high threshold, the voltage is then compared with a third high threshold (step 726). If the sensed voltage exceeds the third high threshold, the board management controller 150 will record the potential error in the system error log in the memory (step 728). If the sensed voltage is lower than the third high threshold, the program will terminate (step 730). In this example, the threshold is determined based on factors such as trace width, trace length, and supply voltage level. The average value can be determined based on the average value of multiple printed circuit board components.

[0086] Although the disclosed embodiments have been described and illustrated with reference to one or more implementations, those skilled in the art will be able to make equivalent changes and modifications after reading and understanding this specification and the accompanying drawings. Furthermore, while a particular feature of the invention may only be disclosed in one of several embodiments, this feature may be combined with one or more other features of other embodiments as needed, and may be advantageous for any particular or specific application.

[0087] Although several embodiments of the invention have been described above, it should be understood that they are merely illustrative and not intended to limit the invention. Many modifications can be made to the disclosed embodiments without departing from the spirit or scope of the invention. Therefore, the breadth and scope of the invention should not be limited to any of the foregoing embodiments. More precisely, the scope of the invention should be defined by the appended claims and their equivalents.

Claims

1. A voltage sensing system, comprising: A printed circuit board has multiple layers, one of which includes a wiring network and a sensing circuit. The sensing circuit includes the wiring network and a sensing point. The sensing circuit is coupled between a voltage supply and ground. The wiring that makes up the sensing circuit is placed near a fault area that is prone to microcracks. as well as A controller, coupled to the sensing point, performs the following operations: Determine the voltage at the sensing point; Compare this voltage with the threshold; and The abnormal circuit conditions in the printed circuit board are determined based on the comparison results.

2. The system of claim 1 further includes a plurality of sensing circuits on other layers of the printed circuit board, each of the sensing circuits including a sensing point.

3. The system of claim 2 further includes a multiplexer having a plurality of inputs and outputs, wherein each of the plurality of inputs is coupled to one of the sensing points, the output is coupled to the controller, and the controller is operated to select one of the sensing points.

4. The system of claim 1, wherein the sensing circuit includes a first resistor, a second resistor and a third resistor, the first resistor being coupled to the voltage supply and the wiring network, the second resistor being coupled to the wiring network and the sensing point, and the third resistor being coupled between ground and the sensing point, wherein the first resistor, the second resistor and the third resistor are multiple wiring segments formed near multiple edges of the layer.

5. The system of claim 1, wherein the abnormal circuit condition is a short circuit between the wiring network of another layer other than the layer, and the voltage exceeds the threshold; Alternatively, the abnormal circuit condition is an open circuit in the wiring network of that layer, and the voltage is below the threshold.

6. A method for determining abnormal circuit conditions in a multilayer printed circuit board, the method comprising: A supply voltage is provided to a sensing circuit on a layer of a printed circuit board, the sensing circuit being contained in a wiring network on the layer, wherein the wiring network on the layer is located near at least one region in the layer that is susceptible to microcracks that could lead to abnormal circuit conditions. Determine the voltage value at the sensing point of the sensing circuit; Compare the voltage value at the sensing point with the voltage threshold. as well as The controller determines whether there is an abnormal circuit condition based on the comparison results.

7. The method of claim 6, wherein the voltage threshold is a predetermined value.

8. The method of claim 6, wherein the voltage threshold is determined by an initial value of the sensing point, which is measured when the printed circuit board is initially powered.

9. The method of claim 6, wherein the abnormal circuit condition is a short circuit between the wiring network of another layer other than the layer, and the voltage value of the sensing point exceeds the voltage threshold; Alternatively, the abnormal circuit condition is an open circuit in the wiring network of the layer, and the voltage value of the sensing point is lower than the voltage threshold.

10. A computer device comprising: Power supply voltage source; A circuit board having multiple layers, each of which has a wiring network, wherein at least one of the layers includes a sensing circuit having the wiring network, sensing points, and multiple wiring segments near multiple edges of the at least one layer to form a circuit between a power supply voltage source and ground, wherein the wiring constituting the sensing circuit is placed near a fault region that is prone to microcracks; and A substrate management controller is coupled to the sensing point. The substrate management controller reads the voltage of the sensing point and compares the voltage with a threshold voltage to determine the abnormal circuit conditions in the circuit board.

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