esd monitor

Abstract

The utility model provides a kind of ESD monitor, the ESD monitor includes shell and the PCB board encapsulated in the shell, main control chip, ESD monitoring interface, detection circuit and human body proximity sensor are integrated on the PCB board;ESD monitoring interface, be located on shell, for connecting external ESD protection link;Detection circuit is connected with main control chip and ESD monitoring interface;Human body proximity sensor is connected with main control chip;Main control chip is configured as the human body existence signal of response human body proximity sensor output, enable detection circuit.The ESD monitor is automatically started by human body proximity sensor and realizes the ESD monitor.The ESD monitor is freed from the dependence of personnel manual start operation, effectively reduces or eliminates the operation oversight caused by personnel intentionally not to start or forget to start monitor, and ensures that the opening rate of ESD monitor reaches 100%.

Description

Technical Field

[0001] This utility model relates to the field of ESD monitoring technology, and in particular to an ESD monitoring device. Background Technology

[0002] Electrostatic discharge (ESD) is extremely destructive to high-precision electronic components, potentially causing product damage, decreased yield, and a surge in after-sales failure rates. Therefore, in manufacturing industries such as electronics, semiconductors, medical devices, and aerospace, ESD protection is a core element in ensuring product reliability, production safety, and supply chain efficiency. To monitor the grounding status of ESD protection links (wrist straps / table mats / equipment) in production stations in real time, ESD monitoring devices are typically deployed for continuous monitoring.

[0003] However, in actual production, some employees have a weak awareness of electrostatic protection and do not actively turn on the ESD monitoring device, which brings hidden dangers to production. Utility Model Content

[0004] In view of this, the present invention provides an ESD monitoring device that can improve the opening rate.

[0005] This utility model provides an ESD monitor, including a housing and a PCB board encapsulated in the housing. The PCB board integrates a main control chip, an ESD monitoring interface, a detection circuit, and a human proximity sensor.

[0006] The ESD monitoring interface is located on the housing and is used to connect to an external ESD protection link;

[0007] The detection circuit is connected to the main control chip and the ESD monitoring interface.

[0008] The human proximity sensor is connected to the main control chip;

[0009] The main control chip is configured to enable the detection circuit in response to a human presence signal output by the human proximity sensor.

[0010] In one embodiment, the housing has a sensing window for the human proximity sensor; the sensing window is located on the front surface, bottom surface, or top surface of the housing.

[0011] In one embodiment, the aperture size of the sensing window is larger than the maximum outer diameter of the probe head of the human proximity sensor.

[0012] In one embodiment, the ESD monitor further includes a sound alarm integrated on the PCB board and connected to the main control chip, and the front, bottom or top surface of the housing is provided with a porous matrix of the sound alarm.

[0013] In one embodiment, the housing includes a first portion and a second portion joined together along the height direction. The first portion includes a top plate, a first end plate, and a second end plate. The first end plate and the second end plate are spaced apart along the length direction of the housing on the side of the top plate facing the second portion. The second portion includes a bottom plate, a first side plate, and a second side plate. The first side plate and the second side plate are spaced apart along the width direction of the housing on the side of the bottom plate facing the first portion.

[0014] In one embodiment, the first portion extends from the docking end in the length direction to form a mounting portion, and the mounting portion is provided with mounting holes.

[0015] In one embodiment, the ESD monitoring interface includes at least one of the following:

[0016] First type: at least one first ESD monitoring interface for connecting an anti-static wrist strap, wherein the first ESD monitoring interface is located on the front surface of the housing;

[0017] The second type: at least one second ESD monitoring interface for connecting a table mat or equipment housing, the second ESD monitoring interface being located on the rear surface of the housing.

[0018] In one embodiment, the ESD monitor further includes at least one of a differential signal communication module, a single-ended signal communication module, and a wireless communication module integrated on the PCB board; all communication modules are connected to the main control chip.

[0019] In one embodiment, the ESD monitor further includes:

[0020] A driver chip integrated on the PCB board and connected to the main control chip; and,

[0021] At least one multiplexed interface is integrated on the PCB board and connected to the output pin of the driver chip; the multiplexed interface is configured as a grounding interface or an external indicator light driver interface, and the multiplexed interface is located on the rear surface of the housing.

[0022] In one embodiment, the ESD monitor further includes multiple status indicator lights integrated on the PCB board and connected to the main control chip. Each status indicator light corresponds to one of the ESD monitoring interfaces and is used to indicate the status of the external ESD protection link connected to the ESD monitoring interface. The status indicator lights are located on the front surface of the housing, and the first ESD monitoring interface and the multiple status indicator lights are arranged at intervals along the length direction of the front surface of the housing.

[0023] In one embodiment, the main control chip includes a PWM output pin and an ADC sampling pin;

[0024] The detection circuit includes an RC charging and discharging circuit, a resistor voltage divider network, and a filter circuit.

[0025] One end of the RC charging and discharging circuit is connected to the PWM output pin of the main control chip, and the other end is connected to the input of the resistor voltage divider network; the output of the resistor voltage divider network is connected to the ESD monitoring interface, and the voltage divider node of the resistor voltage divider network is connected to the input of the filter circuit; the output of the filter circuit is connected to the ADC sampling pin of the main control chip.

[0026] In one embodiment, the filter circuit includes a first resistor, a first capacitor, a second capacitor, a second resistor, and a third resistor;

[0027] The first end of the first resistor is connected to the voltage divider node, and the second end is connected to the first end of the first capacitor; the second end of the first capacitor is connected to the first end of the second capacitor, and the second end of the second capacitor is grounded; the first end of the second capacitor is also connected to the first end of the second resistor, the first end of the third resistor, and the ADC sampling pin; the second end of the second resistor is connected to the power supply; and the second end of the third resistor is grounded.

[0028] The ESD monitor provided by this utility model detects the presence of a human body signal through a human proximity sensor 105, thereby enabling the detection circuit 103 to enter a standby state. This allows for automatic activation of the ESD monitor via the human proximity sensor 105. This ESD monitor eliminates the reliance on manual power-on, effectively reducing or eliminating operational oversights caused by personnel intentionally failing to turn it on or forgetting to turn it on. It ensures a 100% activation rate for the ESD monitor, guaranteeing its effective function during production. Attached Figure Description

[0029] Figure 1 This is a schematic diagram of the structure of an ESD monitoring device in one embodiment.

[0030] Figure 2 This is an exploded view of the ESD monitoring device in one embodiment.

[0031] Figure 3 This is a schematic diagram of the structure of an ESD monitoring device according to an embodiment.

[0032] Figure 4 This is a schematic diagram of the circuit structure of an ESD monitoring device in one embodiment.

[0033] Figure 5 This is a schematic diagram of the circuit structure of an ESD monitoring device in one embodiment.

[0034] Figure 6 This is a schematic diagram of the circuit structure of the detection circuit in one embodiment.

[0035] Figure 7 This is a schematic diagram of the circuit structure of the detection circuit in one embodiment.

[0036] In the diagram: 10. Monitor; 101. Housing; 1012. First part; 10121. First end plate; 10122. Second end plate; 10123. Top plate; 1011. Second part; 10111. First side plate; 10112. Second side plate; 10113. Bottom plate; 1013. Mounting part; 102. Main control chip; 103. Detection circuit; 104. ESD monitoring interface; 1041. First ESD monitoring interface; 1042. Second ESD monitoring interface; 105. Human proximity sensor; 1051. Sensing window; 106. Differential signal Communication module; 1061, RS485 communication chip; 1062, Type-C interface; 107, single-ended signal communication module; 1071, serial communication chip; 1072, Type-B interface; 108, wireless communication module; 109, driver chip; 110, multiplexed interface; 111, sound alarm; 1110, multi-hole matrix; 112, status indicator light; 113, mechanical switch; 114, power management module; 115, power input interface; 116, mounting hole; 20, external ESD protection link; 117, PCB board. Detailed Implementation

[0037] The present invention will be further described below with reference to the accompanying drawings and specific embodiments. It should be noted that, without conflict, the various embodiments or technical features described below can be arbitrarily combined to form new embodiments.

[0038] It should be noted that all directional indicators (such as up, down, left, right, front, back, inside, outside, top, bottom, etc.) in the embodiments of this utility model are only used to explain the relative positional relationship between the components in a certain specific posture (as shown in the figure). If the specific posture changes, the directional indicator will also change accordingly.

[0039] It should also be noted that when a component is referred to as "fixed to" or "set on" another component, the component may be directly on the other component or there may be an intervening component present. When a component is referred to as "connected to" another component, it may be directly connected to the other component or there may be an intervening component present.

[0040] An ESD monitoring device 10, such as Figures 1 to 4As shown, it includes a housing 101 and a PCB board 117 encapsulated within the housing 101. The PCB board 117 integrates a main control chip 102, an ESD monitoring interface 104, a detection circuit 103, and a human proximity sensor 105.

[0041] The ESD monitoring interface 104 is located on the housing 101 and is used to connect to the external ESD protection link 20.

[0042] The detection circuit 103 is connected to the main control chip 102 and the ESD monitoring interface 104.

[0043] The human proximity sensor 105 is connected to the main control chip 102.

[0044] The main control chip 102 is configured to enable the detection circuit 103 in response to the human presence signal output by the human proximity sensor 105.

[0045] In one specific embodiment, the ESD monitor 10 includes a PCB board 117 disposed within a housing 101. This PCB board integrates a main control chip 102, a detection circuit 103, and provides electrical connections for the ESD monitoring interface 104, the human proximity sensor 105, and the various electronic components of the detection circuit 103. The ESD monitoring interface 104 is located on the housing 101 and is connected to the PCB board via a connector or wire. The detection portion of the human proximity sensor 105 is mounted at an appropriate location on the housing 101, and its signal is connected to an interface or processing circuit on the PCB board via a wire.

[0046] Specifically, multiple ESD protection links are typically installed at production workstations to meet the requirements of anti-static production. Common ESD protection links include wrist strap discharge links corresponding to anti-static wrist straps, table mat grounding links corresponding to production equipment mats, and equipment grounding links corresponding to equipment housings.

[0047] The wristband discharge link consists of the operator's skin, wristband, cable, and ground.

[0048] The platform grounding link consists of the platform surface, conductive layer, grounding clip and earth in sequence.

[0049] The equipment grounding link consists of the equipment casing, grounding wire, grounding point, and earth in sequence.

[0050] Antistatic wrist straps are grounded by connecting a built-in resistor with a small resistance value (such as a 1MΩ resistor) in series. When in use, the metal buckle is tightly pressed against the skin. While discharging static electricity from the human body, it limits the current flowing through the body and prevents the risk of electric shock.

[0051] Anti-static table mats are grounded via a resistive grounding wire to discharge static electricity around the desktop. Equipment casing grounding refers to connecting the equipment casing to the earth via a conductive path, serving to prevent electric shock and provide static electricity protection.

[0052] Specifically, the monitoring points of ESD protection link 20 are connected to the ESD monitor via ESD monitoring interface 104, thus enabling ESD protection link 20 to be connected to the ESD monitor. The monitoring points of the ESD protection link refer to specific test nodes on the grounding path of the ESD protection link. For example, an anti-static wrist strap has a connector that can be inserted into the ESD monitoring interface. An anti-static mat has a grounding buckle on its edge, which can be connected to the ESD monitoring interface via a wire and plug. The ESD monitoring interface can also be connected to the grounding bolt of the equipment casing via a wire and plug.

[0053] The detection circuit 103 is connected to the main control chip 102 and the ESD monitoring interface 104, and is used to detect the equivalent impedance or voltage of the ESD protection link, so that the main control chip 102 can obtain the ESD monitoring result based on the detected equivalent impedance or voltage of the ESD protection link.

[0054] In one embodiment, the detection circuit converts the square wave excitation signal sent by the main control chip into a sawtooth wave voltage signal and applies it to the monitoring point of the external ESD protection link, such as the interface of an anti-static wrist strap or the grounding buckle of a table mat. Then, the ADC sampling pin of the main control chip acquires the response voltage change generated by the application of the sawtooth wave voltage signal to the monitoring point after a fixed delay. Based on the response voltage change, the ESD monitoring result of the ESD protection link is obtained.

[0055] ESD monitoring results can include whether the anti-static wrist strap is worn properly, whether the anti-static wrist strap is grounded, whether the human body leakage voltage is normal, whether the equipment casing is grounded, whether the equipment leakage voltage is normal, whether the table mat is grounded, and whether the table mat leakage voltage is normal.

[0056] The output of the human proximity sensor 105 can be connected to one of the pins of the main control chip 102. In one embodiment, the human proximity sensor 105 can be an infrared sensor, radar sensor, etc. When a human target is detected in the sensing area, a human presence signal is sent to the main control chip 102 through this pin.

[0057] The main control chip 102 is configured to enable the detection circuit 103 in response to a human presence signal output by the human proximity sensor 105.

[0058] In one embodiment, one pin of the main control chip 102 is connected to the enable terminal or circuit switch of the detection circuit 103. The main control chip 102 is configured to respond to the presence signal of a human body output by the human proximity sensor 105 and send an enable signal to the enable terminal or circuit switch of the detection circuit 103 through the pin so that the detection circuit 103 turns on and enters a standby state.

[0059] Using this ESD monitor, when the monitor detects a human target through the human proximity sensor 105 in the production process, it sends a human presence signal to the main control chip 102 through the pin. The main control chip 102 then enables the detection circuit 103 to continuously monitor the external ESD protection link 20 through the ESD monitoring interface 104.

[0060] This ESD monitor detects the presence of a human body using a proximity sensor 105, which then enables the detection circuit 103 to enter standby mode, thus automatically activating the ESD monitor via the proximity sensor 105. This eliminates the need for manual operation, effectively reducing or eliminating operational errors caused by personnel intentionally failing to turn on or forgetting to turn on the monitor, ensuring a 100% activation rate and guaranteeing that the ESD monitor can effectively function during production.

[0061] In one embodiment, the housing 101 has a sensing window 1051 for the human proximity sensor 105 to detect outwards. The position of the sensing window 1051 is configured according to the installation height and orientation of the ESD monitor so that the ESD monitor can detect human targets. For example, if the ESD monitor is installed at a low height, the sensing window can be opened on the top or front surface of the housing. If the ESD monitor is installed at a high height, the sensing window can be opened on the bottom or front surface of the housing. Here, the front surface refers to the surface of the housing facing the normal zone area of ​​the human body being measured (such as the facing surface of the ESD monitor when the user is standing or sitting in front of it).

[0062] In one embodiment, the ESD monitor is typically installed at a production workstation to monitor the work surface mats, equipment grounding, and the wearing of anti-static wrist straps by employees. To reduce additional workspace occupation, the ESD monitor can be installed below the workstation surface, such as the lower surface of the workbench. Therefore, for effective monitoring of human targets, a sensing window 1051 is located on the front or bottom surface of the housing, configured with its primary sensing direction facing the space in front of or below the ESD monitor. Thus, the sensing window 1051 is located on the front surface of the housing facing the human body, or on the lower surface of the housing facing the legs / feet of the human body.

[0063] In one embodiment, the ESD monitor can be installed on the floor of the production station. Therefore, to effectively monitor human targets, a sensing window 1051 is located on the front or top surface of the housing, configured so that its primary sensing direction faces the space in front of or above the ESD monitor. Thus, the sensing window 1051 is located on the front surface of the housing facing the human body, or on the upper surface of the housing facing the legs / feet of the human body.

[0064] In this way, the setting position of the sensing window 1051 of the human proximity sensor 105 can meet the actual needs and accurately capture human targets.

[0065] In one embodiment, the aperture size of the sensing window 1051 is larger than the maximum outer diameter of the probe head of the human proximity sensor 105. This reduces or eliminates mechanical obstruction, expands the effective detection angle of the human proximity sensor, and allows the sensing field of the human proximity sensor 105 to pass completely through the sensing window 1051.

[0066] In one embodiment, such as Figure 1 , Figure 2 , Figure 3 and Figure 5 As shown, the ESD monitor also includes a sound alarm 111 integrated on the PCB board 117 and connected to the main control chip 102. When the main control chip 102 detects an ESD protection abnormality in the external ESD protection link, it can drive the sound alarm 111 to emit an audible alarm.

[0067] In one embodiment, the sound alarm 111 uses a buzzer as the sound-generating unit. Inside the housing, a perforated matrix 1110 is formed corresponding to a specific area outside the housing. For example, depending on the installation position of the ESD monitor, the perforated matrix 1110 of the sound alarm is formed on the front surface, bottom surface, or top surface of the housing to ensure effective sound transmission of the alarm.

[0068] The audible alarm can be configured to emit different alarm sounds based on different types of anomalies, thus allowing the type of anomaly to be distinguished by sound. For example, when detecting issues such as improper wearing of an electrostatic wrist strap, equipment malfunction, or leakage voltage, different alarm sounds, such as intermittent or continuous sounds, are emitted to enhance the early warning of anomalies from an auditory perspective.

[0069] In one embodiment, the housing 101 includes a first portion 1012 and a second portion 1011 joined together along the height direction. The first portion includes a top plate 10123, a first end plate 10121, and a second end plate 10122. The first end plate 10121 and the second end plate 10122 are spaced apart along the length direction of the housing on the side of the top plate 10123 facing the second portion 1011. The second portion 1011 includes a bottom plate 10113, a first side plate 10111, and a second side plate 10112. The first side plate 10111 and the second side plate 10112 are spaced apart along the width direction of the housing on the side of the bottom plate 10112 facing the first portion 1012.

[0070] Thus, the first part 1012 of the shell 101 is a U-shaped structure with openings on the left and right sides, including a top plate 10123, a first end plate 10121, and a second end plate 10122. The second part 1011 of the shell 101 is a U-shaped structure with openings at the front and back, including a bottom plate 10113, a first side plate 10111, and a second side plate 10112. The first part 1012 and the second part 1011 can be fitted together to form a closed structure of the shell. This structural design facilitates the assembly of the shell and improves assembly efficiency.

[0071] The first part 1012 extends from the docking end in the length direction to form a mounting part 1013. The mounting part is provided with mounting holes 116 to facilitate fixing the ESD monitor through the mounting holes 116 of the mounting part 1013.

[0072] like Figures 1 to 3 As shown, the ESD monitoring interface includes at least one of the following:

[0073] The first configuration includes at least one first ESD monitoring interface 1041 for connecting an anti-static wrist strap, the first ESD monitoring interface 1041 being located on the front surface of the housing. The first ESD monitoring interface 1041 can thus connect to a wrist strap discharge link. The wrist strap discharge link sequentially includes the operator's skin, the wrist strap, a cable, and ground.

[0074] The second method involves at least one second ESD monitoring interface 1042 for connecting to a platform mat or equipment housing, the second ESD monitoring interface 1042 being located on the rear surface of the housing. Thus, the second ESD monitoring interface 1041 can be connected to a platform mat grounding link. The platform mat grounding link sequentially includes a platform mat surface, a conductive layer, a grounding clip, and earth. And / or, the second ESD monitoring interface 1041 can be connected to an equipment grounding link. The equipment grounding link sequentially includes the equipment housing, a grounding wire, a grounding point, and earth.

[0075] The front surface refers to the surface of the casing facing the normal zone of the human body being measured (such as the facing side of the ESD monitor when the user is standing or sitting in front of it). The rear surface refers to the side opposite to the front surface.

[0076] Operationally, workers are more likely to plug and unplug the anti-static wrist strap connector through the first ESD monitoring interface 1041, while plugs on the work surface or equipment housing are less frequently needed to be plugged and unplugged through the second ESD monitoring interface 1042. Therefore, to facilitate worker operation, the first ESD monitoring interface 1041 is located on the front surface of the housing, and the second ESD monitoring interface 1042 is located on the rear surface of the housing. This layout allows workers to directly see and quickly plug and unplug the wrist strap connector, while concealing the grounding wire for low-frequency operations, thus balancing operational efficiency and site cleanliness.

[0077] In this embodiment, the ESD monitoring interface 104 may include at least one first ESD monitoring interface 1041 for connecting an anti-static wrist strap, and at least one second ESD monitoring interface 1042 for connecting a table mat or equipment housing.

[0078] This allows for monitoring of the wearing status of anti-static wrist straps, the grounding status of the work surface, and the grounding status of the equipment casing. Furthermore, the ESD monitor supports the use of universal anti-static wrist straps, eliminating the need for specialized accessories and further reducing the factory's investment costs in ESD protection.

[0079] In one embodiment, such as Figure 1 , Figure 2 , Figure 3 and Figure 5 As shown, the ESD monitor also includes at least one of the following integrated on the PCB board 117: a differential signal communication module 106, a single-ended signal communication module 107, and a wireless communication module 108. All three modules are connected to the main control chip 102. This provides the ESD monitor with multiple communication methods.

[0080] The differential signal communication module 106 refers to a communication module based on the differential transmission principle. It transmits signals with opposite phases on two cables using complementary voltage signals, and achieves data transmission by detecting the voltage difference at the receiving end, enabling long-distance data transmission. The differential signal communication module 106 can be an RS485 communication module or a CAN bus communication module.

[0081] The single-ended signal communication module 107 refers to a communication module that transmits signals through a single cable, suitable for short-distance, high-efficiency transmission. The single-ended signal communication module 107 may include RS-232 modules, UART modules, etc.

[0082] Specifically, the differential signal communication module 106 includes an RS485 communication chip 1061 disposed in the housing 101, and at least one Type-C interface 1062 disposed on the housing 101 and connected to the RS485 communication chip 1061. The Type-C interface 1062 is disposed on the rear surface of the housing.

[0083] In a specific embodiment, an RS485 communication chip can be used to connect dual Type-C interfaces. Based on the RS485 industrial bus standard, and in conjunction with dual Type-C interfaces, long-distance, multi-device networking communication between multiple ESD monitors can be achieved. Multiple monitors communicate in series via RS485 modules, thereby enabling the aggregation and transmission of data from multiple monitors, or the receipt of remote device control commands, adapting to the large-scale networking needs of factories.

[0084] The single-ended signal communication module 107 includes a serial communication chip 1071 inside the housing 101, and at least one Type-B interface 1072 disposed in the housing 101 and connected to the serial communication chip 1071. The Type-B interface 1072 is disposed on the rear surface of the housing.

[0085] The Type-B interface 1072, which uses serial communication, supports local connection between the ESD monitor and terminals such as computers. This is used for parameter configuration and monitoring data reading and analysis during the development and debugging phase, making it easier for engineers to optimize equipment performance.

[0086] The wireless communication module 108 can be a WIFI communication module, a 4G module, a 5G module, etc. Utilizing wireless network data transmission, ESD monitoring data can be uploaded to a server / cloud in real time, helping managers remotely and in real-time monitor the protection status of the production site. It can also receive configuration commands from a remote server, promoting intelligent and networked management and eliminating the limitations of wired connections.

[0087] Based on the three communication modules mentioned above, a three-level communication link can be constructed, realizing a fully digital closed loop for ESD protection in the production site, from configuration to monitoring and management. Placing the less frequently used Type-B interface 1072 and Type-C interface 1062 on the rear surface of the housing optimizes cable management, reduces interface loosening caused by user contact, and improves reliability.

[0088] Among them, the local configuration link based on the single-ended signal communication module uses a combination of USB-to-serial port and A55A packet header protocol to quickly complete device parameter configuration. The field networking link based on the RS485 communication module, based on the RS485 communication standard and A0 / A1 frame structure protocol, supports hostless serial networking of N devices. The remote transmission link based on the wireless communication module utilizes the ESP8266 WIFI module and AT command set protocol to achieve cloud synchronization of monitoring data and seamless integration with the MES system.

[0089] In one embodiment, such as Figures 1 to 5 The ESD monitoring device also includes:

[0090] A driver chip 109 integrated on the PCB board 117 and connected to the main control chip 102; and,

[0091] At least one multiplexed interface 110 is integrated on the PCB board 117 and connected to the output pin of the driver chip 109; the multiplexed interface 110 is configured as a grounding interface or an external indicator light driving interface, and the multiplexed interface 110 is located on the rear surface of the housing.

[0092] The driver chip is used to drive the relevant load. In one embodiment, the driver chip is an A4950T driver chip.

[0093] The multiplexed interface 110 can be used as both a grounding interface for the ESD monitor and a driver interface for external indicator lights, allowing connection to external indicator lights. The external indicator lights can be installed in a more conspicuous location, making it easier for personnel in distant or different areas to view the status of the external ESD protection link. In one embodiment, the external indicator light can be a dual-color light, displaying green when normal and red when abnormal, thus quickly indicating ESD protection anomalies within the area.

[0094] In this embodiment, a driver chip is used to drive the relevant loads, which, together with the grounding and dual-color LED interfaces, enhances the effect of long-distance visual management and ensures the stability of the grounding function and external indicator lights. Placing the low-frequency multiplexed interface 110 on the rear surface of the housing optimizes cable management, reduces interface loosening caused by user touch, and improves reliability.

[0095] In one embodiment, the ESD monitor further includes multiple status indicator lights 112 integrated on the PCB board 117 and connected to the main control chip 102. Each status indicator light 112 corresponds to one of the ESD monitoring interfaces 104, used to indicate the status of the external ESD protection link connected to the ESD monitoring interface 104 (including grounding status and whether charge discharge is abnormal). The status indicator lights 112 are located on the front surface of the housing. Figures 1 to 5As shown, with two first ESD monitoring interfaces 1041 for connecting anti-static wrist straps and two second ESD monitoring interfaces 1042 for connecting mats or equipment, the ESD monitor is equipped with four status indicator lights 112. Each status indicator light 112 corresponds to one ESD monitoring interface and indicates the status of the connected external ESD protection link. To facilitate viewing by personnel on the production site, information about the indicated external ESD protection link can also be displayed around the indicator lights.

[0096] In one embodiment, the status indicator can be a dual-color light with three display states: green, red, and off. When the ESD monitor is not turned on, it is in the off state; when not connected or the ESD protection status of the connected external ESD protection link is abnormal, it displays red; and when the ESD protection status of the connected external ESD protection link is normal, it displays green. Thus, workers can identify the status of the ESD protection link at their workstation by the color of the status indicator light.

[0097] like Figures 1 to 3 As shown, the first ESD monitoring interface 1041 and the multiple status indicator lights 112 are arranged at intervals along the length of the front surface of the housing, which makes it convenient for users to view and operate.

[0098] In one embodiment, such as Figure 1 , Figure 2 , Figure 3 and Figure 5 As shown, the ESD monitor may also include a mechanical switch 113 integrated on the PCB board 117 and connected to the main control chip 102, used as a control switch for the monitor. The mechanical switch 113 can be a toggle switch. The mechanical switch 113 is located on the front surface of the housing 101 for convenient user operation. The mechanical switch 113 provides a hardware-level operation mode, supporting manual setting of device operating modes and parameters, such as turning specific monitoring functions on / off and switching monitoring thresholds, flexibly adapting to different production scenario requirements.

[0099] In one embodiment, such as Figure 1 , Figure 2 , Figure 3 and Figure 5 As shown, the ESD monitor also includes a power management module 114 integrated on the PCB board 117 and connected to the main control chip 102, and a power input interface 115 connected to the power management module 114.

[0100] The power input interface 115 serves as the external power input for the device. It can use a 12V DC interface to connect to a 12V DC power supply, providing basic power support for the operation of the device.

[0101] The power management module 114 is responsible for the allocation, conversion, and voltage stabilization of the equipment's power. It receives power input from the 12V DC interface and converts it into the 3.3V and 5V voltages required by internal modules such as the main control chip, human proximity sensor, and communication chip, ensuring a stable power supply for each module.

[0102] like Figures 1 to 3 As shown, for ease of viewing by users, interfaces and switches that require frequent operation and use can be placed on the front surface of the ESD monitor, while interfaces that require less frequent operation can be placed on the rear surface opposite the front surface. When in use, the front surface of the ESD monitor should face the operator for easy access.

[0103] Specifically, the frequently used ESD monitoring interface 1041 (for connecting the anti-static wrist strap), status indicator 112, and mechanical switch 113 are located on the front surface, facing the operator during use. The less frequently used interfaces—power input interface 115, Type-C interface 1062, Type-B interface 1072, multiplex interface 110, and the second ESD monitoring interface 1042 (for connecting a table mat or equipment housing)—are located on the rear surface. This optimizes cable management, reduces interface loosening caused by user contact, and improves reliability.

[0104] Specifically, the mechanical switch 113, the multiple status indicator lights 112, and the first ESD monitoring interface 1041 are arranged sequentially at intervals along the length of the front surface of the housing. The second ESD monitoring interface 1042, the multiplexed interface 110, the Type-B interface 1072, and the Type-C interface 1062 are arranged sequentially at intervals along the length of the rear surface of the housing. This eliminates the thickness redundancy of traditional side-by-side layouts and reduces the thickness of the ESD monitor.

[0105] In one embodiment, such as Figure 6 As shown, the main control chip 102 includes a PWM output pin and an ADC sampling pin.

[0106] The detection circuit 103 includes an RC charging / discharging circuit 1031, a resistor voltage divider network 1032, and a filter circuit 1033. One end of the RC charging / discharging circuit 1031 is connected to the PWM output pin of the main control chip 102, and the other end is connected to the input terminal of the resistor voltage divider network 1032. The output terminal of the resistor voltage divider network 1032 is connected to the ESD monitoring interface 104, and the voltage divider nodes of the resistor voltage divider network 1032 are connected to the input terminal of the filter circuit 1033. The output terminal of the filter circuit 1033 is connected to the ADC sampling pin of the main control chip 102.

[0107] Based on the detection circuit 103 described above, the main control chip 102 outputs a PWM square wave excitation signal to the RC charging and discharging circuit 1031 through the PWM output pin. The RC charging and discharging circuit 1031 converts the PWM signal into a charging and discharging voltage signal. The charging and discharging voltage signal is input to the resistor voltage divider network 1032 for voltage division. The output of the resistor voltage divider network 1032 is connected to the ESD monitoring interface 104. Test current is injected into the ESD monitoring interface through the resistor voltage divider network 1032. The response voltage of the external ESD protection link 104 can be detected through the voltage divider node. The response voltage is filtered by the filter circuit 1033 to remove noise and is sent to the ADC pin of the main control chip 102.

[0108] like Figure 7 As shown, the RC charging and discharging circuit 1031 includes a third capacitor C3 and a fourth resistor R4. One end of the third capacitor C3 is connected to the PWM pin of the main control chip 102, and the other end of the third capacitor C3 is connected to one end of the fourth resistor R4, and is also connected to the input terminal of the resistor divider network 1032. The other end of the fourth resistor R4 is grounded.

[0109] The resistor divider network 1032 includes a fifth resistor R5 and a sixth resistor R6 connected in series, with the voltage divider node between the two resistors. The other end of the sixth resistor R6 is connected to an ESD monitoring interface 104, which is used to connect to an external ESD protection link, thereby including the equivalent impedance Rx of the external ESD protection link into a portion of the equivalent resistance of the charge / discharge circuit.

[0110] The equivalent impedance Rx of the external ESD protection link is incorporated into the equivalent resistance of the RC charging and discharging circuit. Changes in the equivalent impedance Rx of the protection link alter the RC charging and discharging time constant τ, thereby changing the waveform characteristics of the excitation signal (sawtooth wave). Therefore, by detecting the characteristics of the voltage at the ADC sampling point (caused by waveform changes), the resistance value of the equivalent impedance Rx of the external ESD protection link can be indirectly measured to determine the reliability of the ESD protection link grounding.

[0111] When the PWM square wave excitation signal is high, current charges the third capacitor C3 through the fourth resistor R4. When the input square wave is low, the third capacitor C3 discharges through the fourth resistor R4. Under continuous square wave input, the RC charging and discharging circuit outputs a sawtooth wave voltage, which is then applied to the external ESD protection link connected to the ESD monitoring interface 104 through the resistor voltage divider network 1032. The response voltage of the external ESD protection link 104 can be detected through the voltage divider node. The response voltage is filtered by the filter circuit 1033 to remove noise and then sent to the ADC pin of the main control chip 102 for sampling.

[0112] Therefore, by using fixed-delay differential sampling under square wave excitation, the equivalent impedance and voltage of the external ESD protection link can be detected according to the change of response voltage.

[0113] Specifically, according to the capacitor charging formula V(t)=Vcc·(1―e ―t / (RC) )

[0114] Where R is the equivalent resistance of the RC charging and discharging circuit (including the equivalent impedance of the protection link), and C is the charging and discharging capacitor.

[0115] Then, the equivalent resistance of the RC charging and discharging circuit is decomposed according to the formula, and the equivalent impedance of the ESD protection link is calculated.

[0116] After the square wave is triggered, the ADC acquires the first voltage difference between the excitation signal at times T0 (initial) and T1 (delay) within the same signal period. Since the first voltage difference is inversely proportional to the equivalent resistance, the resistance value to be measured can be deduced by using the calibration curve or formula, and the electrostatic loop impedance, equipment resistance, etc., can be monitored.

[0117] Leakage voltage (such as the AC voltage from equipment leakage) is superimposed on the charging and discharging circuit, causing the reference voltage at time T0 to deviate. By detecting the second voltage difference at time T0 of different signal cycles of the excitation signal, and comparing the second voltage difference with the reference value without leakage voltage, the magnitude of the leakage voltage can be determined, thereby determining whether there is an abnormal charge discharge in the protection link.

[0118] The square wave signal provides stable triggering and avoids DC drift interference. The small capacitance value accelerates the charging and discharging speed, making it suitable for high-frequency scenarios such as ESD pulse monitoring.

[0119] The detection circuit 103 is simple and low-cost, and can monitor key ESD data.

[0120] like Figure 7 As shown, the filter circuit 1033 includes a first resistor R1, a first capacitor C1, a second capacitor C2, a second resistor R2, and a third resistor R3.

[0121] The first end of the first resistor R1 is connected to the voltage divider node, and the second end is connected to the first end of the first capacitor C1; the second end of the first capacitor C1 is connected to the first end of the second capacitor C2, and the second end of the second capacitor C2 is grounded; the first end of the second capacitor C2 is also connected to the first end of the second resistor R2, the first end of the third resistor R3, and the ADC sampling pin; the second end of the second resistor R2 is connected to the power supply; the second end of the third resistor R3 is grounded.

[0122] In this circuit, the first resistor R1, the first capacitor C1, and the second capacitor C2 form a low-pass filter. The second resistor R2 and the third resistor R3 form a resistor divider, establishing a DC bias voltage on the ADC sampling pin to ensure that the measured response voltage signal falls within the ADC's measurement range. The second capacitor C2 is connected in parallel between the ADC input and ground, effectively filtering out high-frequency noise. This filtering circuit improves the sampling quality of the response voltage.

[0123] The ESD monitoring device of this application organically combines the human proximity sensor 105 with the detection and enforcement functions of the ESD monitoring device to ensure a 100% alarm activation rate. By monitoring the ESD protection link of the production station, it greatly reduces ESD failure events caused by improper personnel operation and equipment grounding problems, significantly improving the ESD protection level of personnel and equipment. By configuring multiple communication modules, it can provide the ESD monitoring device with multiple communication methods, thereby realizing multiple communication functions. By setting up audible alarms and status indicator lights, it provides multiple forms of alarms from both visual and auditory perspectives.

[0124] The above embodiments are merely preferred embodiments of this utility model and should not be construed as limiting the scope of protection of this utility model. Any non-substantial changes and substitutions made by those skilled in the art based on this utility model shall fall within the scope of protection claimed by this utility model.

Claims

1. An ESD monitoring device, characterized in that, It includes a housing and a PCB board encapsulated within the housing, wherein the PCB board integrates a main control chip, an ESD monitoring interface, a detection circuit, and a human proximity sensor; The ESD monitoring interface is located on the housing and is used to connect to an external ESD protection link; The detection circuit is connected to the main control chip and the ESD monitoring interface. The human proximity sensor is connected to the main control chip; The main control chip is configured to enable the detection circuit in response to a human presence signal output by the human proximity sensor.

2. The ESD monitoring device according to claim 1, characterized in that, The housing has a sensing window for the human proximity sensor; the sensing window is located on the front surface, bottom surface, or top surface of the housing.

3. The ESD monitoring device according to claim 2, characterized in that, The aperture size of the sensing window is larger than the maximum outer diameter of the probe of the human proximity sensor.

4. The ESD monitoring device according to claim 1, characterized in that, The ESD monitoring device also includes a sound alarm integrated on the PCB board and connected to the main control chip, and the front, bottom or top surface of the housing is provided with a multi-hole matrix of the sound alarm.

5. The ESD monitoring device according to any one of claims 1 to 4, characterized in that, The housing includes a first part and a second part joined together along the height direction. The first part includes a top plate, a first end plate and a second end plate. The first end plate and the second end plate are spaced apart along the length direction of the housing on the side of the top plate facing the second part. The second part includes a bottom plate, a first side plate and a second side plate. The first side plate and the second side plate are spaced apart along the width direction of the housing on the side of the bottom plate facing the first part.

6. The ESD monitoring device according to claim 5, characterized in that, The first part extends from the docking end in the length direction to form a mounting part, and the mounting part is provided with mounting holes.

7. The ESD monitoring device according to claim 5, characterized in that, The ESD monitoring interface includes at least one of the following: First type: at least one first ESD monitoring interface for connecting an anti-static wrist strap, wherein the first ESD monitoring interface is located on the front surface of the housing; The second type: at least one second ESD monitoring interface for connecting a table mat or equipment housing, the second ESD monitoring interface being located on the rear surface of the housing.

8. The ESD monitoring device according to claim 5, characterized in that, The ESD monitor also includes at least one of a differential signal communication module, a single-ended signal communication module, and a wireless communication module integrated on the PCB board; all communication modules are connected to the main control chip.

9. The ESD monitoring device according to claim 8, characterized in that, The ESD monitoring device also includes: A driver chip integrated on the PCB board and connected to the main control chip; and, At least one multiplexed interface is integrated on the PCB board and connected to the output pin of the driver chip; the multiplexed interface is configured as a grounding interface or an external indicator light driver interface, and the multiplexed interface is located on the rear surface of the housing.

10. The ESD monitoring device according to claim 7, characterized in that, The ESD monitor also includes multiple status indicator lights integrated on the PCB board and connected to the main control chip. Each status indicator light corresponds to one of the ESD monitoring interfaces and is used to indicate the status of the external ESD protection link connected to the ESD monitoring interface. The status indicator lights are located on the front surface of the housing, and the first ESD monitoring interface and the multiple status indicator lights are arranged at intervals along the length direction of the front surface of the housing.

11. The ESD monitoring device according to claim 1, characterized in that, The main control chip includes a PWM output pin and an ADC sampling pin; The detection circuit includes an RC charging and discharging circuit, a resistor voltage divider network, and a filter circuit. One end of the RC charging and discharging circuit is connected to the PWM output pin of the main control chip, and the other end is connected to the input of the resistor voltage divider network; the output of the resistor voltage divider network is connected to the ESD monitoring interface, and the voltage divider node of the resistor voltage divider network is connected to the input of the filter circuit; the output of the filter circuit is connected to the ADC sampling pin of the main control chip.

12. The ESD monitoring device according to claim 11, characterized in that, The filter circuit includes a first resistor, a first capacitor, a second capacitor, a second resistor, and a third resistor; The first end of the first resistor is connected to the voltage divider node, and the second end is connected to the first end of the first capacitor; the second end of the first capacitor is connected to the first end of the second capacitor, and the second end of the second capacitor is grounded; the first end of the second capacitor is also connected to the first end of the second resistor, the first end of the third resistor, and the ADC sampling pin; the second end of the second resistor is connected to the power supply; and the second end of the third resistor is grounded.

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