Memory device write protection circuit and vehicle-mounted image acquisition device

Abstract

The application relates to a memory device write protection circuit and a vehicle-mounted image acquisition device. The application is applied to a memory device, the memory device comprising a write protection enable pin and a communication port; the communication port is used for communication with an upper device; the write protection enable pin is not connected with the upper device; the memory device write protection circuit comprises a first resistor and a voltage control component, wherein: an input / output power supply is connected with the write protection enable pin of the memory device in sequence through the first resistor and the voltage control component, and is used for outputting a preset voltage signal to the write protection enable pin; the voltage control component is used for switching the level state of the write protection enable pin based on external triggering, so that the write protection function of the memory device is activated or turned off. The data security of the memory device can be improved by adopting the memory device write protection circuit.

Description

Technical Field

[0001] This application relates to the field of information security technology, and in particular to a write protection circuit for a storage device and an in-vehicle image acquisition device. Background Technology

[0002] With the development of the automobile manufacturing industry, the information security of in-vehicle equipment has had a significant impact on users' driving experience and safety.

[0003] Currently, devices such as camera modules and ECU main controllers often incorporate storage devices. To prevent malicious tampering of critical information such as configuration parameters during use, a serial chip or other host device typically controls the write protection enable pin level of the storage device. After configuration parameters are completed, the pin level is switched to enable or disable write protection. However, remote users can control the serial chip to switch the write protection pin level again via communication commands, allowing write protection to be remotely deactivated. Therefore, the risk of malicious tampering with stored content remains, potentially affecting the normal operation of devices using this storage device.

[0004] This shows that traditional technologies still have the problem of low data security in storage devices. Utility Model Content

[0005] Therefore, it is necessary to provide a write protection circuit for storage devices and an in-vehicle image acquisition device that can improve the data security of storage devices in response to the above-mentioned technical problems.

[0006] In a first aspect, this application provides a write protection circuit for a storage device, which includes a write protection enable pin and a communication port; the communication port is used to communicate with a host device; the write protection enable pin is not connected to the host device.

[0007] The write protection circuit for the memory device includes a first resistor and a voltage control component, wherein: the input / output power supply is connected to the write protection enable pin of the memory device in sequence through the first resistor and the voltage control component, for outputting a preset voltage signal to the write protection enable pin; the voltage control component is used to switch the level state of the write protection enable pin based on an external trigger, so as to activate or deactivate the write protection function of the memory device.

[0008] In one embodiment, the voltage control component includes a unidirectional conduction unit, a power control switch, and a power protection device; wherein,

[0009] The positive terminal of the unidirectional conduction unit is connected to the write protection enable pin and the output terminal of the first resistor, respectively, and the negative terminal is connected to the output terminal of the power control switch and the input terminal of the power protection device, respectively. The input terminal of the power control switch is connected to a power supply, and the output terminal of the power protection device is grounded. The power protection device is non-recoverably disconnected when the input current exceeds a preset current threshold or the input voltage exceeds a preset voltage threshold. The preset voltage threshold is higher than the preset voltage signal and lower than the output voltage of the power supply. The power control switch is used to control the power supply and the power protection device to be connected or disconnected.

[0010] In one embodiment, the write protection function is activated when the write protection enable pin is high and disabled when it is low;

[0011] When the power control switch is turned on, the power protection device is turned off, and the preset voltage signal is output to the write protection enable pin, so that the write protection enable pin is pulled high and the write protection function is activated.

[0012] In one embodiment, the voltage control component further includes a loop control switch; the write protection function is activated when the write protection enable pin is low and deactivated when it is high.

[0013] The input / output power supply is connected to the control terminal of the loop control switch and the input terminal of the unidirectional conduction unit, respectively, and is connected to the write protection enable pin in sequence through the first resistor, the loop control switch, and the write protection enable pin; the loop control switch is turned on when the control terminal is low and turned off when the control terminal is high.

[0014] When the power control switch is turned on, the power protection device is turned off, the control terminal of the loop control switch is pulled high, the loop control switch is turned off, the write protection enable pin is pulled low, and the write protection function is activated.

[0015] In one embodiment, the voltage control component further includes a fourth resistor, through which the input / output power supply is connected to the positive terminal of the unidirectional conduction unit and the control terminal of the loop control switch, respectively.

[0016] In one embodiment, the voltage control component further includes a voltage divider resistor, and the write protection enable pin is also grounded through the voltage divider resistor.

[0017] In one embodiment, the host device is connected to the control terminal of the power control switch, and the power control switch responds to the switch control signal of the host device to control the power supply and the power protection device to be turned on or off.

[0018] In one embodiment, the voltage control component further includes a first test point that mates with an external fixture pin; the fixture pin is grounded; wherein:

[0019] The first test point is connected to the input / output power supply and the write protection enable pin respectively; when the fixture pin contacts the first test point, the preset voltage signal is output to the write protection circuit enable pin so that the write protection enable pin switches the level and the write protection function is turned off.

[0020] In one embodiment, the write protection function is activated when the write protection enable pin is low and deactivated when it is high.

[0021] The voltage control component includes a voltage divider resistor and a second test point that mates with an external fixture pin; the input / output power supply is connected to the write protection enable pin and the voltage divider resistor respectively through the first resistor and the second test point; the voltage divider resistor is grounded;

[0022] When the fixture pin contacts the second test point, the preset voltage signal is output to the write protection enable pin, so that the write protection enable pin is pulled high and the write protection function is turned off.

[0023] Secondly, this application provides an in-vehicle image acquisition device, which includes an image sensor, a serial chip, a memory chip, and a memory device write protection circuit as described above. The serial chip is communicatively connected to the image sensor and the memory chip, respectively. The memory device write protection circuit is connected to the write protection enable pin of the memory chip. The image sensor and the memory device write protection circuit share the input / output power supply.

[0024] The aforementioned write protection circuit for the storage device and the vehicle-mounted image acquisition device are connected to the write protection enable pin of the storage device via an input / output power supply, which is then connected in sequence through a first resistor and a voltage control component. This connection outputs a preset voltage signal to the write protection enable pin. The voltage control component switches the level state of the write protection enable pin based on an external trigger, thereby activating or deactivating the write protection function of the storage device. Since the write protection enable pin is not directly connected to the host device, its activation or deactivation must rely on a physical or controlled local triggering mechanism, rather than a remotely interferable communication protocol. By switching the output level in response to an external trigger signal and by initiating level switching through a physical or local signal, the voltage control component controls the activation or deactivation of the write protection function. This effectively cuts off the path for remote tampering with the write protection state via communication commands, thus fundamentally preventing remote attackers from sending commands to deactivate write protection through the host device. By isolating write protection control from remotely accessible communication links, the storage device's ability to resist malicious tampering during operation is enhanced, effectively improving the data security of the storage device. Attached Figure Description

[0025] Figure 1 This is a block diagram of a write protection circuit for a storage device in one embodiment;

[0026] Figure 2 This is a block diagram of the write protection circuit of a memory chip in one embodiment;

[0027] Figure 3 A circuit diagram of a write-protection circuit for a storage device in another embodiment;

[0028] Figure 4 A circuit diagram of a write-protection circuit for a storage device in another embodiment;

[0029] Figure 5 A circuit diagram of a write-protection circuit for a storage device in another embodiment;

[0030] Figure 6 A circuit diagram of a write-protection circuit for a storage device in another embodiment;

[0031] Figure 7 This is a structural block diagram of an in-vehicle image acquisition device in one embodiment. Detailed Implementation

[0032] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application.

[0033] In one embodiment, such as Figure 1As shown, a write protection circuit for a storage device is provided, which is applied to a storage device. The storage device includes a write protection enable pin and a communication port; the communication port is used to communicate with a host device; the write protection enable pin is not connected to the host device.

[0034] The write protection circuit for the memory device includes a first resistor and a voltage control component, wherein: the input / output power supply is connected to the write protection enable pin of the memory device in sequence through the first resistor and the voltage control component, and is used to output a preset voltage signal to the write protection enable pin; the voltage control component is used to switch the level state of the write protection enable pin based on an external trigger, so as to activate or deactivate the write protection function of the memory device.

[0035] The storage device can receive data read / write commands from a host device via a communication port and determine whether to allow write operations to the internal storage based on the level state of the write protection enable pin. The write protection enable pin is not connected to the host device, ensuring it is not controlled through the communication port or the host device, thus protecting the storage of configuration parameters or other critical data. For example, the storage device can receive read / write commands from the communication port and level signals from a voltage control component, and use internal logic to determine whether to respond to the write operation request, obtaining a stored data response signal.

[0036] For example, the storage device can receive and send data via a serial communication protocol to achieve information interaction with the host device, thereby supporting the host device to read data and write configurations to the storage device. Taking an in-vehicle device as an example, the host device may include, but is not limited to, an ECU main control chip, an in-vehicle communication module, etc. It is understood that the host device may also be a circuit that directly or indirectly performs read and / or write operations with the storage device in other scenarios, which is not limited in this embodiment.

[0037] The input / output power supply is connected to the first resistor. In this embodiment, the input / output power supply can provide a stable voltage required for circuit operation and can provide a high-level signal to the write protection enable pin. In this embodiment, the voltage of the input / output power supply can be processed by the first resistor and voltage control components to form a stable level signal, thereby ensuring that the write protection enable pin receives a voltage that meets the logic level requirements.

[0038] In this embodiment, the activation or deactivation of the write protection function depends on the high or low level of the write protection enable pin. In one exemplary embodiment, the write protection function is activated when the write protection enable pin is high and deactivated when it is low; in another exemplary embodiment, the write protection function is activated when the write protection enable pin is low and deactivated when it is high. The write protection enable pin can control the activation or deactivation of the internal write protection logic of the storage device by receiving an external level signal. Furthermore, the write protection enable pin can receive a level signal from a voltage control component, triggering the internal write protection mechanism through changes in the level state, thereby achieving control without relying on a communication link and ensuring that the write protection state is not interfered with by remote commands.

[0039] Understandably, in traditional technologies, the write protection enable pin is directly controlled by the host device, thus posing a risk of remote tampering. In this embodiment, the output level can be changed based on an external trigger to control the high and low levels of the write protection enable pin. For example, the external triggering in this embodiment is performed physically rather than through signal commands.

[0040] In one exemplary embodiment, the voltage control component can be a circuit with an open circuit. The output or blocking of a preset voltage signal can be achieved by manually adjusting the position of the components, such as by toggling a mechanical switch or physical button. The output or blocking of the preset voltage signal can also be achieved by replacing the component body, thereby effectively avoiding the write protection function being turned off by remote command control and improving data security. Other methods that require external force to intervene in the conduction can also be used, which are not limited in this embodiment.

[0041] Taking the case of a vehicle camera module being remotely intruded during vehicle operation as an example, the write protection circuit of the storage device in this embodiment can be such that although the host device receives a remotely forged configuration modification command, it cannot send a command to change the write protection state through the communication port because the write protection enable pin is not connected to the host device. At this time, the voltage control component only responds to the external trigger signal from the physical button inside the vehicle body, and maintains the write protection active state in the absence of local trigger, so as to ensure that the lens calibration parameters in the storage device are not tampered with and to ensure the normal operation of the image acquisition function.

[0042] This embodiment provides a write protection circuit for a storage device. An input / output power supply is sequentially connected to the write protection enable pin of the storage device via a first resistor and a voltage control component. This power supply outputs a preset voltage signal to the write protection enable pin. The voltage control component switches the level state of the write protection enable pin based on an external trigger, thereby activating or deactivating the write protection function of the storage device. Since the write protection enable pin is not directly connected to the host device, its activation or deactivation relies on a physical or controlled local triggering mechanism, rather than a remotely controllable communication protocol. By switching the output level only in response to an external trigger signal and initiating level switching via a physical or local signal, the voltage control component controls the activation or deactivation of the write protection function. This effectively cuts off the path for remote tampering with the write protection state via communication commands, thus fundamentally preventing remote attackers from sending commands to deactivate write protection via a host device. By isolating write protection control from remotely accessible communication links, the storage device's ability to resist malicious tampering during operation is enhanced, effectively improving the data security of the storage device.

[0043] In one embodiment, the voltage control component includes a unidirectional conduction unit, a power control switch, and a power protection device; wherein...

[0044] The positive terminal of the unidirectional conduction unit is connected to the write protection enable pin and the output terminal of the first resistor, respectively, and the negative terminal is connected to the output terminal of the power control switch and the input terminal of the power protection device, respectively. The input terminal of the power control switch is connected to the power supply, and the output terminal of the power protection device is grounded. The power protection device is non-recoverably disconnected when the input current exceeds a preset current threshold or the input voltage exceeds a preset voltage threshold. The preset voltage threshold is higher than the preset voltage signal and lower than the output voltage of the power supply. The power control switch is used to control the power supply and the power protection device to be turned on or off.

[0045] The power protection device connects its input terminal to the negative terminal of the unidirectional conduction unit and the output terminal of the power control switch. Its output terminal is grounded. This device is used to permanently disconnect the circuit when the input current exceeds a preset current threshold or the input voltage exceeds a preset voltage threshold, thus permanently cutting off the grounding path. Combined with the controlled conduction action of the power control switch, this ensures that the write-protected state cannot be remotely restored or modified after the power protection device disconnects. It is understood that traditional protection mechanisms are reversible and software-controlled, posing a risk of remote reset. This solution, however, prevents state rollback through hardware-level irreversible disconnection. In an exemplary embodiment, the power protection device can be an overvoltage protection device. This overvoltage protection device receives a voltage signal applied from the power supply via the power control switch and undergoes physical damage or melting when a preset voltage threshold is reached, forming a permanent open circuit. For example, the overvoltage protection device can be a one-time fuse-type TVS diode, or a fusible ceramic varistor, a dedicated one-time overvoltage fuse, or other devices that are irreversible after disconnection. In another exemplary embodiment, the power protection device can be an overcurrent protection device. This overcurrent protection device receives a current signal from the power supply via a power control switch and, through its internal structure, physically damages or fuses when a preset current threshold is reached, creating a permanent open circuit. Examples of overcurrent protection devices include fuses and integrated chip overcurrent protection circuits. The non-resettable disconnection means that during the operation of the power protection device, it permanently loses its conducting capability after triggering, ensuring that once the grounding path is broken, it cannot be restored.

[0046] The unidirectional conduction unit has its positive terminal connected to the write protection enable pin and the output terminal of the first resistor, and its negative terminal connected to the output terminal of the power control switch and the input terminal of the power protection device. It can be used to limit current, ensuring that current can only flow from the first resistor side to the power control switch side, preventing reverse current interference with the level stability of the write protection enable pin. Furthermore, the unidirectional conduction unit can receive a preset voltage signal or a preset current, and use its unidirectional conduction characteristic to block the reverse current path, ensuring that the write protection enable pin level is not affected by fluctuations in the state of the power control switch side. In a specific embodiment, the unidirectional conduction unit can include a semiconductor diode to implement the unidirectional conduction function, or it can use an active rectification structure composed of MOSFETs, etc.

[0047] The power control switch, with its input connected to the power supply and its output connected to the negative terminal of the unidirectional conduction unit and the input terminal of the power protection device, can be used to control the on / off relationship between the power supply and the power protection device. After programming, it can be triggered to conduct by a local command or manually toggled, causing the power supply to apply an overvoltage or overcurrent signal to the power protection device to trigger it to disconnect. It is understood that traditional technologies lack a physical locking mechanism for the protection state switching process. This solution uses a controllable switch to precisely initiate irreversible protection actions. In this embodiment, the power control switch can receive a trigger signal for controlling the switch action. This signal originates from a controlled command after local programming. Upon receiving the command, the circuit closes, allowing the power supply to output a high-voltage signal to the power protection device, thus transmitting the power supply's output voltage to the power protection device in the conduction state. Alternatively, it can be manually toggled to achieve manual circuit breaking.

[0048] The power supply is connected to the input terminal of the power control switch and can be used to provide a voltage source that is higher than a preset voltage signal and sufficient to trigger the operation of the power protection device. This voltage source is independent of the input / output power supply or is generated by a boost circuit. For example, the power supply can be a high-voltage DC power supply module independent of the input / output power supply, or it can be configured with a boost circuit to derive the required high voltage from the main power supply, etc. This embodiment is not limited to this.

[0049] A preset voltage threshold, serving as a response parameter for the power supply protection device, can be used to determine its disconnection timing. It can also be used to set the voltage threshold at which the power supply protection device experiences an irreversible disconnection. This threshold is higher than a preset voltage signal but lower than the power supply output voltage, ensuring that the power supply protection device can be reliably triggered under controlled conditions. Similarly, a preset current threshold, also a response parameter for the power supply protection device, can be used to determine its disconnection timing. It can also be used to set the current threshold at which the power supply protection device experiences an irreversible disconnection. This threshold is lower than the power supply output current, thereby ensuring that the power supply protection device can be reliably triggered under controlled conditions.

[0050] For example, in a scenario where the vehicle-mounted camera module enters the operational phase after completing factory configuration, the write protection circuit for the memory device in this embodiment can be implemented during the production process. After the memory device completes parameter writing, the system issues a local trigger command to turn on the power control switch, and the power supply applies voltage to the power protection device through the power control switch. When the current exceeds its capacity, the power protection device performs an irreversible disconnection, permanently cutting off the grounding loop. Subsequently, the input / output power supply continuously outputs a high-level signal to the write protection enable pin through the first resistor and the unidirectional conduction unit, ensuring that the memory device is always in a write protection active state. Even if the communication port is subjected to a remote attack during vehicle operation, because the write protection enable pin is not connected to the host device and the power protection device has been physically disconnected, the attacker cannot remove the write protection, and the critical configuration data remains secure.

[0051] This embodiment provides a write protection circuit for a storage device. Upon triggering, a power protection device permanently cuts off the grounding path and prevents remote recovery. A unidirectional conduction unit prevents reverse current interference with the write protection enable pin level. A power control switch is turned on under local command control to initiate an irreversible disconnection process. The power supply provides sufficient high voltage to trigger the power protection device. A preset voltage threshold ensures reliable response of the power protection device under controlled conditions. The irreversible disconnection achieves physical-level state locking. This allows the write protection function to be activated by a one-time hardware action after programming, blocking the possibility of remote attackers removing write protection through the communication port. This effectively enhances the storage device's resistance to malicious tampering during operation.

[0052] In one embodiment, the write protection function is activated when the write protection enable pin is high and disabled when it is low.

[0053] When the power control switch is turned on, the power protection device is turned off, and the preset voltage signal is output to the write protection enable pin, so that the write protection enable pin is pulled high and the write protection function is activated.

[0054] In one embodiment, the voltage control component further includes a loop control switch; the write protection function is activated when the write protection enable pin is low and deactivated when it is high.

[0055] The input / output power supply is connected to the control terminal of the loop control switch and the input terminal of the unidirectional conduction unit, respectively, and is connected to the write protection enable pin in sequence through the first resistor, the loop control switch, and the write protection enable pin. The loop control switch is turned on when the control terminal is low and turned off when the control terminal is high.

[0056] When the power control switch is turned on, the power protection device is turned off, the control terminal of the circuit control switch is pulled high, the circuit control switch is turned off, the write protection enable pin is pulled low, and the write protection function is activated.

[0057] The loop control switch has its control terminal connected to the input / output power supply, its input terminal connected to a first resistor, and its output terminal connected to a write protection enable pin. This allows it to control the path from the input / output power supply to the write protection enable pin based on the control terminal's voltage level. When the control terminal is low, the loop control switch is on, allowing a preset voltage signal to pass. When the control terminal is high, it is off, cutting off the path. This off state can be triggered by an overvoltage or overcurrent event. In the event of overvoltage or overcurrent, the power protection device disconnects, and the preset voltage signal is output to the control terminal of the loop control switch, causing a short circuit in the loop control switch and thus blocking the conventional power control path to prevent remote intervention.

[0058] It is understood that in traditional technologies, the write protection pin level can be remotely reconfigured via power supply or communication signals. This embodiment, through the locking off mechanism of the loop control switch, prevents manipulation of the write protection state via the power supply. In an exemplary embodiment, the loop control switch can receive a level signal from the input / output power supply, and trigger a state switch of the internal switching element through a change in the control terminal level. A low level triggers conduction, and a high level triggers deactivation. Its deactivation action is linked to the deactivation of the power protection device, thereby realizing the function of transmitting a preset voltage signal or transmitting it to the write protection enable pin. Furthermore, the loop control switch can include, but is not limited to, using an N-channel MOSFET with an inverting drive structure to achieve low-level conduction, or using an analog switch with an enable terminal configured to be active low, etc. This embodiment does not limit this.

[0059] This embodiment provides a write protection circuit for a storage device. A loop control switch is introduced into the voltage control component. Its control terminal is connected to the input / output power supply, the input terminal is connected to the input / output power supply via a first resistor, and the output terminal is connected to a write protection enable pin. The loop control switch is turned on when the control terminal is low, allowing a preset voltage signal to be transmitted to the write protection enable pin to activate the write protection function. It is turned off when the control terminal is high, cutting off the path. When the power control switch is on, the power protection device is irreversibly disconnected due to power supply issues, simultaneously pulling up the control terminal of the loop control switch, causing it to enter the off state and blocking the path from the input / output power supply to the write protection enable pin. The loop control switch achieves internal write protection by responding to changes in the control terminal level. The switching element's state transitions from low level to conduction and high level to disconnection, creating a physical blockade of the conventional control path. After an overvoltage or overcurrent event is triggered, the write protection enable pin remains low, ensuring continuous write protection effectiveness. Since the circuit control switch's shutdown is driven by the irreversible power protection device, and the write protection enable pin is not directly connected to the host device, remote attackers cannot change its level state by manipulating the power supply or communication port, thus blocking the possibility of remotely deactivating write protection. This enhances the irreversibility and anti-interference capability of the write protection state, prevents deactivation of write protection through remote intervention, and significantly improves the storage device's ability to resist malicious tampering during operation, thereby enhancing data security.

[0060] In one embodiment, the voltage control component further includes a fourth resistor, through which the input / output power supply is connected to the positive terminal of the unidirectional conduction unit and the control terminal of the loop control switch, respectively.

[0061] In this embodiment, one end of the fourth resistor is connected to the input / output power supply, and the other end is connected to the positive terminal of the unidirectional conduction unit and the control terminal of the loop control switch. It can be used to connect between the input / output power supply and the positive terminal of the unidirectional conduction unit and the control terminal of the loop control switch, acting as a voltage divider and current limiter. This ensures a stable bias voltage at the control terminal of the loop control switch, preventing false triggering due to power fluctuations and achieving stable control of the write protection enable pin level. By introducing the fourth resistor, this embodiment enhances the stability and physical isolation of the control path. For example, the fourth resistor can be a high-precision thin-film resistor, a thick-film chip resistor with strong anti-interference capabilities, or a power resistor with a shielded structure to improve circuit stability.

[0062] In one embodiment, the voltage control component also includes a voltage divider resistor, and the write protection enable pin is also grounded through the voltage divider resistor.

[0063] One end of the voltage divider resistor is electrically connected to the write protection enable pin, and the other end is electrically connected to ground. It can be used to perform voltage division processing on the current preset voltage signal when a preset voltage signal is received, thereby preventing the instability of the preset voltage signal from causing additional effects on the level determination of the pin.

[0064] In one embodiment, the host device is connected to the control terminal of the power control switch, and the power control switch responds to the switch control signal of the host device to control the power supply and power protection device to be turned on or off.

[0065] In this embodiment, the power control switch has its control terminal connected to the host device, its input terminal connected to the power supply, and its output terminal connected to the input terminal of the power protection device. In this embodiment, the power control switch can respond to a switch control signal issued by the host device, controlling the on / off relationship between the power supply and the power protection device. Upon receiving a trigger signal, it turns on, causing the power supply to apply an overvoltage or overcurrent signal to the power protection device to trigger its irreversible disconnection, achieving an effect that, once triggered, cannot be recovered by software or remote commands. Furthermore, the power control switch can be one or more of the following: an N-channel MOSFET, an optocoupler relay, or an analog switch chip. The gate of the N-channel MOSFET serves as the control terminal, driven by a GPIO signal from the host device, and is used to turn on once after programming to trigger the protection mechanism.

[0066] Taking the vehicle ECU entering the operation stage after completing the factory parameter burning as an example, the write protection circuit of the storage device in this embodiment can be on the production line. After the storage device is configured, the host device sends a switch control signal to the control terminal of the power control switch through the communication port to turn it on. The power supply then applies voltage or current to the power protection device. When the voltage or current exceeds its preset threshold, the power protection device performs an irreversible disconnection, permanently cutting off the grounding path. After that, the write protection enable pin always maintains the write protection function in the off state. Even if the communication port is remotely attacked after the vehicle is put into use, the write protection state cannot be lifted because the power protection device has been physically disconnected and there is no other recovery path. Therefore, the critical data can be kept from being tampered with, ensuring information security.

[0067] This embodiment provides a write protection circuit for storage devices. After configuration, the host device sends a switch control signal to trigger the power control switch to turn on, thereby causing the power supply to apply an overvoltage or overcurrent signal to the power protection device, resulting in an irreversible disconnection of the power protection device and permanently cutting off its grounding path. The power control switch responds to the control signal from the host device to achieve a one-time conduction of the power supply path. After triggering, the physical circuit maintains the write protection enable pin at a high level. This achieves the technical effect of locking the write protection function by irreversible hardware changes while allowing the host device to participate in the initial configuration, blocking the possibility of remote malicious tampering with the write protection state, and improving the data security of the storage device.

[0068] In one embodiment, the voltage control component further includes a first test point that mates with an external fixture pin; the fixture pin is grounded; wherein:

[0069] The first test point is connected to the input / output power supply and the write protection enable pin respectively. When the fixture pin contacts the first test point, the preset voltage signal is output to the write protection circuit enable pin so that the write protection enable pin switches its level and the write protection function is turned off.

[0070] The first test point can be electrically connected to the input / output power supply and write protection enable pin. Its physical location can be exposed on the board surface for contact with external fixture pins. It can be used as a local physical interface in the voltage control component to cooperate with external fixture pins to achieve controlled shutdown of the write protection function.

[0071] When the jig pins come into contact, a low-resistance path is formed through grounding.

[0072] For example, the write protection function is configured to be activated when the write protection enable pin is high and deactivated when it is low. When the fixture pin is in contact, a preset voltage signal is sent to the first test point, and the write protection enable pin is pulled low, thereby disabling the write protection function.

[0073] In a further embodiment, taking an embodiment including a loop control switch as an example, when the fixture pin contacts and is grounded, the control terminal level of the loop control switch is pulled low, so that the preset voltage signal can be sent to the write protection enable pin again, triggering the write protection function to be turned off.

[0074] Taking the write protection function as an example, which is activated when the enable pin is high and deactivated when it is low, when the jig pin is in contact with and grounded, the preset voltage signal is switched to the low-impedance path, the enable pin is pulled low, thereby triggering the write protection function to be deactivated.

[0075] Understandably, by using the first test point in conjunction with the fixture, it can be ensured that state switching can only be triggered through physical contact in a controlled environment such as the production line. Furthermore, the first test point can be a test point in the form of an exposed metal pad, or it can be a metal cylindrical terminal that can be contacted by a spring pin; the fixture pin can be, for example, a spring-loaded probe structure, a fixed metal contact, or a positioning clamp.

[0076] This embodiment provides a write protection circuit for a storage device, which includes a first test point that cooperates with an external fixture pin via a voltage control component; the fixture pin is grounded; wherein: the first test point is connected to the input / output power supply and the write protection enable pin respectively; when the fixture pin contacts the first test point, a preset voltage signal is output to the write protection circuit enable pin, so that the write protection enable pin switches its level and the write protection function is turned off. Through the first test point as a local physical interface, the write protection function remains active when not in contact, and when contacted by the external fixture pin, a low-resistance path is formed through grounding, forcibly switching the level to turn off the write protection. This operation relies on physical contact rather than communication commands, thereby ensuring that the write protection state switching only occurs in a controlled environment. It can achieve the technical effect that the write protection state switching relies on physical contact operation and cannot be remotely simulated or interfered with through a communication link. The write protection function is activated by default during product operation, achieving a significant enhancement of the anti-tampering capability of stored data and improving data security.

[0077] In one embodiment, the write protection function is activated when the write protection enable pin is low and disabled when it is high.

[0078] The voltage control component includes a voltage divider resistor and a second test point that mates with an external fixture pin; the input / output power supply passes sequentially through the first resistor and the second test point, and is connected to the write protection enable pin and the voltage divider resistor respectively; the voltage divider resistor is grounded;

[0079] When the fixture pin contacts the second test point, a preset voltage signal is output to the write protection enable pin, which pulls the write protection enable pin high and disables the write protection function.

[0080] One end of the voltage divider resistor is connected to the connection node between the second test point and the write protection enable pin, and the other end is grounded. This can be used to pull the node where the write protection enable pin is located to ground, forming a default low-level path, and ensuring that the write protection function remains active when there is no external trigger.

[0081] The second test point serves as the connection node between the first resistor and the write protection enable pin, providing an electrical access point for physical contact with the external fixture pin. Under normal conditions, the second test point is in an open-circuit state; that is, the preset voltage signal of the input / output power supply cannot be output to the write protection enable pin, causing the write protection enable pin to remain at a low level.

[0082] When the external fixture pins make contact, the input / output power supply outputs a high level to the write protection enable pin through the contact point via the first resistor. Based on the matching resistance values ​​of the voltage divider resistor and the first resistor, it can be ensured that the high-level signal can effectively drive the write protection enable pin. For example, the second test point can be an exposed metal pad for pin contact, or a spring-loaded interface terminal can be used to enhance contact stability.

[0083] Taking the temporary disabling of write protection for updating configuration parameters during the production line configuration phase of an on-board ECU as an example, the write protection circuit for the storage device in this embodiment can be as follows: In the production environment, an external fixture pin contacts the second test point, causing the input / output power supply to apply a high level to the write protection enable pin through the first resistor, and the write protection function is temporarily disabled; at this time, the host device can safely write configuration data through the communication port; after the writing is completed, the pin is removed, the voltage divider resistor pulls the node back to a low level, and the write protection function automatically resumes its active state; since this process must rely on physical contact, remote attackers cannot simulate this operation after the vehicle is put into use, ensuring that the data cannot be tampered with during operation.

[0084] This embodiment provides a write protection circuit for storage devices. By physically contacting an external fixture pin with a second test point to establish a high-level path, write protection is temporarily disabled. This operation relies on physical contact and cannot be simulated through remote communication. Combined with the stabilizing pull-down effect of a voltage divider resistor on the node to prevent noise interference, the change of write protection status is strictly limited to local physical intervention conditions, blocking the possibility of remote command to remove write protection. This enhances the ability of stored data to resist malicious tampering during operation, thereby improving data security.

[0085] In one embodiment, the write protection function is activated when the write protection enable pin is low and disabled when it is high.

[0086] The voltage control component includes a voltage divider resistor and a second test point that mates with an internal fixture pin; one end of the internal fixture pin is connected to the positive terminal of the first resistor, and the input / output power supply passes through the first resistor and the second test point in sequence, and is connected to the write protection enable pin and the voltage divider resistor respectively; the voltage divider resistor is grounded;

[0087] When the fixture pin contacts the second test point, the preset voltage signal bypasses the first resistor through the internal fixture pin and is output to the write protection enable pin, so that the write protection enable pin is pulled high and the write protection function is turned off.

[0088] To more clearly illustrate the technical solution of this application, a detailed embodiment is also provided.

[0089] Currently, information security protection for camera modules is primarily achieved by enabling the write-protection (WP) function of the memory chip. Conventional circuits connect the write-protection enable pin of the memory chip to a high level, while simultaneously connecting it to a general-purpose port on the serial chip. Connecting it to a high level ensures that the module is write-protected under normal conditions. Connecting it to the general-purpose port allows the write-protection function to be disabled during parameter writing to the module in the manufacturing process by configuring the general-purpose port to output a low level (pulling down the WP port). Figure 2 As shown.

[0090] During the production process, the parameters of the camera module are written in the finished product stage of the module. First, the serial chip is used to configure the general port to output a low level, and the write protection function of the memory chip is turned off. Second, all configuration parameters are written into the memory chip. Finally, the serial chip is used to reconfigure the general port to output a high level, and the write protection function of the memory chip is turned on again, and the module is in a state where it cannot be written.

[0091] However, the above method is subject to tampering. If a third party uses the ECU / HOST master controller to configure the serial chip's corresponding general purpose port (GPIO) to a low level through commands such as IIC, the write protection function will be turned off, and the module parameters in the storage device can be tampered with. Therefore, it is necessary to modify the protection logic based on conventional methods to implement the module information security protection method.

[0092] Based on this, in one embodiment, such as Figure 3 As shown, a write protection circuit for a memory device is provided, including resistors R0 and R1 and a test pad TP1. The EEPROM memory device triggers the write protection function to switch between high and low levels on the WP pin. The WP pin is grounded through resistor R1 and connected to the test pad TP1. The input / output power supply VDDIO is connected to the test pad TP1 through resistor R0. When the fixture probe contacts the test pad TP1, the fixture probe is connected to a high level through resistor R0, where the value of R0 is much smaller than R1 to ensure effective pull-up. When the probe contacts the test pad TP1, the WP pin level switches to high, deactivating the write protection function. When the probe is removed, WP returns to a low level due to the pull-down resistor, reactivating the write protection function.

[0093] In one embodiment, such as Figure 4As shown, the EEPROM storage device has its WP enable pin open. The input / output power supply is connected to the WP pin via resistor R1, which is also connected to test pad 1. In this embodiment, the voltage control component, in conjunction with an externally grounded fixture pin, uses the fixture pin to press against the test point led out from the write protection port of the storage chip during the data writing phase. The pin is then connected to the ground of the PCB, which puts the write protection port at a low level, thus disabling write protection. Configuration / calibration parameters can then be written to the storage chip via the IIC interface of the serial chip. After the data writing is complete, removing the fixture pin will pull the WP level of the storage chip high again, reactivating the write protection function. Since there is no GPIO connected to the WP port, after the module is manufactured and subsequently installed in the vehicle, the WP will be pulled high by default when the camera module is powered on, thus enabling the write protection function.

[0094] In one embodiment, such as Figure 5 As shown, the write protection port of the EEPROM memory chip is connected to a high level through a pull-up resistor R1, and simultaneously grounded through diode D1 and fuse FUSE F1. In the default state, the write protection port voltage is close to the diode's forward voltage, less than the low-level threshold, and is thus considered low-level, meaning the write protection function is not enabled, allowing internal parameter data to be programmed during the finished product manufacturing stage. Simultaneously, the circuit is connected in series with the power supply VCC and fuse FUSE F1 via electronic switch S1. After the programming process on the production line is completed, switch S1 is closed, turning VCC through fuse FUSE F1 to ground, creating a loop similar to a short circuit, causing the fuse to blow non-resettable. Because fuse F1 is open, diode D1 cannot conduct, and the write protection port of the memory chip is pulled high through resistor R1, enabling the write protection function. In this state, whether S1 is conducting or not cannot affect the write protection port state. Therefore, it is impossible to disable write protection through configuration of a general-purpose port using a serial chip at the software level, and thus, it is impossible to modify the configuration parameters within the memory chip.

[0095] In one embodiment, such as Figure 6As shown: Q1 is a P-MOS transistor, and Q2 is an N-MOS transistor. Assume R1=1K, R2=10K, R3=10K, and VDDIO=1.8V. Upon initial power-up, since the source (S) of Q1 is greater than its gate (ignoring the forward voltage drop of D1, which is close to 0V, the loop path is VDDIO to R2 to D1 to F1 to GND), the control pin of MOS transistor Q1 is low and conducts. R1 and R3 divide the voltage, the WP port is pulled up, and write protection is disabled. After programming on the production line, the gate (G) level of MOS transistor Q2 is pulled high through the GPIO port, turning on MOS transistor Q2. The power supply VCC is shorted to ground GND through fuse FUSE F1. After fuse FUSE F1 blows, the gate (G) level of MOS transistor Q1 rises, and MOS transistor Q1 is not turned on. The WP enable pin of the FLASH memory chip is pulled down to ground GND through resistor R3, enabling write protection.

[0096] The write protection circuit for storage devices provided in the above embodiments, through hardware circuit design, provides secure protection for information on the storage devices. This effectively prevents external remote means from attempting to tamper with the parameters within the camera, and forms a closed-loop logic in its protection method. Furthermore, this embodiment requires fewer new components, has lower costs, and has minimal impact on the component layout on the PCB, thus also featuring low production costs.

[0097] It is understood that the write protection circuit for the memory device in this embodiment can be used not only for vehicle camera modules, but also for the protection of other memory devices that need to be protected from remote malicious control, such as integrated vehicle camera modules and automotive ECU main control boards.

[0098] In one embodiment, an in-vehicle image acquisition device is provided, which includes an image sensor, a serial chip, a memory chip, and a write protection circuit for the memory device as described above. The serial chip is communicatively connected to both the image sensor and the memory chip. The write protection circuit for the memory device is connected to the write protection enable pin of the memory chip. The image sensor and the write protection circuit for the memory device share a common input / output power supply.

[0099] The memory device write protection circuit enables the write protection function of the memory chip, allowing the image sensor to acquire images and transmit data based on the critical information stored in the memory chip. When the write protection function is activated, the critical information acquired by the image sensor from the memory chip remains unaltered, ensuring that the acquired content is not affected by remote control and improving security.

[0100] In one embodiment, such as Figure 7As shown, the image sensor and the serial chip transmit image and communication signals, while the serial chip and the memory chip transmit communication signals. The write protection enable pin of the memory chip is connected to the test point and the first resistor (i.e., the pull-up resistor), respectively. The power management chip provides a power supply path for the serial chip, as well as input / output power voltage.

[0101] In one embodiment, an in-vehicle main control device is provided, which includes a control component, a serial chip, a memory chip, and a memory device write protection circuit as described above. The serial chip is communicatively connected to both the control component and the memory chip. The memory device write protection circuit is connected to the write protection enable pin of the memory chip. The control component and the memory device write protection circuit share the same input / output power supply.

[0102] The memory device write protection circuit enables the write protection function of the memory chip. The control component can then perform data processing and device control based on the critical information stored in the memory chip. When the write protection function is activated by the memory device write protection circuit, the critical configuration information obtained by the control component from the memory chip remains unaltered, thus ensuring that the data on which processing is based is not affected by remote control and improving security.

[0103] The modules in the aforementioned vehicle-mounted image acquisition device and vehicle-mounted main control device can be implemented entirely or partially through software, hardware, or a combination thereof. These modules can be embedded in the processor of a computer device in hardware form or independent of it, or stored in the memory of a computer device in software form, so that the processor can call and execute the corresponding operations of each module.

[0104] It should be noted that the user information (including but not limited to user device information, user personal information, etc.) and data (including but not limited to data used for analysis, data stored, data displayed, etc.) involved in this application are all information and data authorized by the user or fully authorized by all parties.

[0105] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0106] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of this patent application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this application should be determined by the appended claims.

Claims

1. A write protection circuit for a storage device, characterized in that, Applied to a storage device, the storage device includes a write-protect enable pin and a communication port; the communication port is used to communicate with a host device; the write-protect enable pin is not connected to the host device. The write protection circuit for the memory device includes a first resistor and a voltage control component, wherein: the input / output power supply is connected to the write protection enable pin of the memory device in sequence through the first resistor and the voltage control component, for outputting a preset voltage signal to the write protection enable pin; the voltage control component is used to switch the level state of the write protection enable pin based on an external trigger, so as to activate or deactivate the write protection function of the memory device.

2. The write protection circuit for storage devices according to claim 1, characterized in that, The voltage control component includes a unidirectional conduction unit, a power control switch, and a power protection device; wherein... The positive terminal of the unidirectional conduction unit is connected to the write protection enable pin and the output terminal of the first resistor, respectively, and the negative terminal is connected to the output terminal of the power control switch and the input terminal of the power protection device, respectively. The input terminal of the power control switch is connected to a power supply, and the output terminal of the power protection device is grounded. The power protection device is non-recoverably disconnected when the input current exceeds a preset current threshold or the input voltage exceeds a preset voltage threshold. The preset voltage threshold is higher than the preset voltage signal and lower than the output voltage of the power supply. The power control switch is used to control the power supply and the power protection device to be connected or disconnected.

3. The write protection circuit for storage devices according to claim 2, characterized in that, The write protection function is activated when the write protection enable pin is high and disabled when it is low. When the power control switch is turned on, the power protection device is turned off, and the preset voltage signal is output to the write protection enable pin, so that the write protection enable pin is pulled high and the write protection function is activated.

4. The write protection circuit for storage devices according to claim 2, characterized in that, The voltage control component also includes a loop control switch; the write protection function is activated when the write protection enable pin is low and deactivated when it is high. The input / output power supply is connected to the control terminal of the loop control switch and the input terminal of the unidirectional conduction unit, respectively, and is connected to the write protection enable pin in sequence through the first resistor, the loop control switch, and the write protection enable pin; the loop control switch is turned on when the control terminal is low and turned off when the control terminal is high. When the power control switch is turned on, the power protection device is turned off, the control terminal of the loop control switch is pulled high, the loop control switch is turned off, the write protection enable pin is pulled low, and the write protection function is activated.

5. The write protection circuit for storage devices according to claim 4, characterized in that, The voltage control component further includes a fourth resistor, through which the input / output power supply is connected to the positive terminal of the unidirectional conduction unit and the control terminal of the loop control switch, respectively.

6. The write protection circuit for storage devices according to claim 4, characterized in that, The voltage control component also includes a voltage divider resistor, and the write protection enable pin is grounded through the voltage divider resistor.

7. The write protection circuit for storage devices according to claim 3, characterized in that, The host device is connected to the control terminal of the power control switch. The power control switch responds to the switch control signal of the host device to control the power supply and the power protection device to be turned on or off.

8. The write protection circuit for a memory device according to any one of claims 1 to 6, characterized in that, The voltage control component further includes a first test point that mates with an external fixture pin; the fixture pin is grounded; wherein: The first test point is connected to the input / output power supply and the write protection enable pin respectively; when the fixture pin contacts the first test point, the preset voltage signal is output to the write protection circuit enable pin so that the write protection enable pin switches the level and the write protection function is turned off.

9. The write protection circuit for a storage device according to claim 1, characterized in that, The write protection function is activated when the write protection enable pin is low and disabled when it is high. The voltage control component includes a voltage divider resistor and a second test point that mates with an external fixture pin; the input / output power supply is connected to the write protection enable pin and the voltage divider resistor respectively through the first resistor and the second test point; the voltage divider resistor is grounded; When the fixture pin contacts the second test point, the preset voltage signal is output to the write protection enable pin, so that the write protection enable pin is pulled high and the write protection function is turned off.

10. A vehicle-mounted image acquisition device, characterized in that, The vehicle-mounted image acquisition device includes an image sensor, a serial chip, a memory chip, and a memory device write protection circuit as described in any one of claims 1 to 9, wherein the serial chip is communicatively connected to the image sensor and the memory chip respectively, the memory device write protection circuit is connected to the write protection enable pin of the memory chip, and the image sensor and the memory device write protection circuit share the input / output power supply.

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