A synchronous pulse generation circuit and electronic control unit

Abstract

The application discloses a synchronous pulse generation circuit, and relates to the field of circuits. When a following condition is met, a source follower outputs a following signal consistent with the voltage change trend of the first end of the capacitor; when the following condition is not met, the source follower outputs a voltage signal corresponding to a third power supply, so that the output signal of the whole circuit is based on the output signal of the first end of the capacitor and the third power supply, and the output signal will not change with the change of a sensor load at the rear end. On the premise that parameters are consistent, the rising edge and the falling edge of the synchronous pulse signal are stable in rate, and the rising edge and the falling edge of the synchronous pulse signal can be controlled by adjusting the parameters of specific devices in the circuit. The output signal is stable and controllable, which is beneficial to the accurate realization of the control process of the sensor by an ECU, and improves the safety and reliability of the automobile controller. The application further discloses an electronic control unit, which has the same beneficial effects as the above-mentioned synchronous pulse generation circuit.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of circuit, in particular to a synchronous pulse generation circuit. The present application also relates to an electronic control unit. BACKGROUND

[0002] With the increasing attention to automobile safety, designers need to add more sensors and related control systems to achieve the corresponding protection function, but a common interface is needed between these sensors and systems to achieve reliable communication. The PSI5 (Peripheral Sensor Interface) protocol is an open, constantly evolving protocol standard based on automotive applications, which can be used to replace LIN (Local Interconnect Network). The PSI5 protocol has been widely used in automobiles at present, such as airbags, vehicle dynamics control, power systems and related fields, and can be applied to data communication between ECUs (Electronic Control Units) and sensors in automobile controllers. Usually, a pair of twisted wires is used to connect between the ECU and the sensor, and the connection can be made by asynchronous connection mode, synchronous parallel bus mode, synchronous general bus mode and synchronous daisy chain bus mode. In the synchronous mode, the data communication between the ECU and the sensor is usually by means of a synchronous pulse, and the ECU sends a high-level voltage signal as a synchronous pulse on the basis of supplying power to the sensor. After the sensor detects the signal of the synchronous pulse, it sends its own current signal according to the pre-set time slot to transmit data to the ECU, thereby completing the data communication between the ECU and the sensor. However, the output synchronous pulse in the prior art varies with the change of the sensor load, which is not conducive to the accurate implementation of the control process of the ECU to the sensor. SUMMARY

[0003] The purpose of the present application is to provide a synchronous pulse generation circuit and an electronic control unit. The output synchronous pulse signal of the entire generation circuit is based on the output signal of the first end of the capacitor and the third power supply, and does not change with the change of the sensor load at the rear end. Under the premise of consistent parameters, the rising and falling edges of the synchronous pulse signal are stable, and the rising and falling edges of the synchronous pulse signal can be controlled by adjusting the parameters of the specific devices in the circuit. The output signal is stable and controllable, which is conducive to the accurate implementation of the control process of the ECU to the sensor, and improves the safety and reliability of the automobile controller.

[0004] To solve the above technical problems, the present application provides a synchronous pulse generation circuit applied to an electronic control unit in an automobile controller, which comprises a control module, a capacitor and a source follower.

[0005] The first input end of the control module is connected to a start signal, the second input end is connected to a first reference voltage, the third input end is connected to a first power supply, the fourth input end is connected to a second reference voltage, the first end of the capacitor is connected to the fifth input end of the control module, the output end of the control module and the first input end of the source follower, the second end is grounded, the second input end of the source follower is connected to a second power supply, the third input end is connected to a third power supply, and the output end is the output end of the generation circuit of the synchronization pulse.

[0006] The control module is used for charging the capacitor when the start signal is detected and the voltage of the first end of the capacitor is less than the first reference voltage, discharging the capacitor when the voltage of the first end of the capacitor is greater than the first reference voltage, and maintaining the voltage of the first end of the capacitor at the second reference voltage when the start signal is not detected or the capacitor is discharged to the second reference voltage; the second power supply is greater than the third power supply, the third power supply is greater than the first power supply; the first reference voltage is greater than the second reference voltage.

[0007] The source follower is used for outputting a signal consistent with the voltage change trend of the first end of the capacitor when the voltage of the first end of the capacitor meets the following condition, and outputting a signal consistent with the voltage change trend of the third power supply when the voltage of the first end of the capacitor does not meet the following condition.

[0008] Preferably, the control module comprises a comparison module, a charging module and a discharging module.

[0009] The first input end of the comparison module is connected to a first reference voltage, the second input end is connected to the first end of the capacitor, the enable end is connected to a start signal, and the output end is connected to the control end of the charging module and the control end of the discharging module respectively; the input end of the charging module is connected to a first power supply, and the output end is connected to the first end of the capacitor; the first input end of the discharging module is connected to a second reference voltage, and the output end is connected to the first end of the capacitor.

[0010] The comparison module is used for controlling the discharging module to be turned off when the start signal is detected and the voltage of the first end of the capacitor is less than the first reference voltage, controlling the charging module to be turned on to charge the capacitor when the voltage of the first end of the capacitor is greater than the first reference voltage, and controlling the discharging module to maintain the voltage of the first end of the capacitor at the second reference voltage when the start signal is not detected or the capacitor is discharged to the second reference voltage.

[0011] Preferably, the charging module comprises a charging switch and a charging current source;

[0012] The input end of the charging current source is connected with the first power supply, the output end is connected with the first end of the charging switch, the second end of the charging switch is connected with the first end of the capacitor, and the control end of the charging switch is connected with the output end of the comparison module;

[0013] The charging switch is used for being turned on based on the control of the comparison module when the start signal is detected and the voltage of the first end of the capacitor is less than the first reference voltage, being turned off based on the control of the comparison module when the capacitor is charged to the voltage of the first end of the capacitor being greater than the first reference voltage, and being turned off based on the control of the comparison module when the start signal is not detected or the capacitor is discharged to the second reference voltage.

[0014] Preferably, the comparison module comprises a comparator and a flip-flop;

[0015] The first input end of the comparator is connected with the first reference voltage, the second input end is connected with the first end of the capacitor, the enable end is connected with the start signal, the output end is connected with the first input end of the flip-flop, the second input end of the flip-flop is connected with the first power supply, the set end is connected with the start signal, and the output end is connected with the control end of the charging module and the control end of the discharging module respectively;

[0016] The flip-flop is used for outputting low level based on the low level output by the comparator when the start signal is detected and the voltage of the first end of the capacitor is less than the first reference voltage, to control the discharging module to be turned off and the charging module to be turned on to charge the capacitor, outputting high level based on the high level output by the comparator when the capacitor is charged to the voltage of the first end of the capacitor being greater than the first reference voltage, to control the charging module to be turned off and the discharging module to be turned on to discharge the capacitor, and outputting high level based on the high level output by the comparator when the start signal is not detected or the capacitor is discharged to the second reference voltage, to control the discharging module to maintain the voltage of the first end of the capacitor at the second reference voltage.

[0017] Preferably, the discharging module comprises a first operational amplifier, a discharging switch and a discharging current source;

[0018] The non-inverting input terminal of the first operational amplifier is connected to a second reference voltage, the inverting input terminal is connected to the output terminal of the first operational amplifier, and the output terminal of the first operational amplifier is also connected to the first terminal of the discharge current source, the second terminal of the discharge current source is connected to the first terminal of the discharge switch, the second terminal of the discharge switch is connected to the first terminal of the capacitor, and the control terminal is connected to the output terminal of the comparison module.

[0019] The discharge switch is used to be turned off based on the control of the comparison module when the start signal is detected and the voltage at the first terminal of the capacitor is less than the first reference voltage, to be turned on based on the control of the comparison module when the capacitor is charged to the voltage at the first terminal of the capacitor being greater than the first reference voltage, and to be turned on based on the control of the comparison module when the start signal is not detected or the capacitor is discharged to the second reference voltage.

[0020] Preferably, a boost module is further included.

[0021] The first input terminal of the boost module is connected to the first terminal of the capacitor, and the output terminal is connected to the first input terminal of the source follower.

[0022] Preferably, the boost module includes a second operational amplifier, a first voltage dividing resistor and a second voltage dividing resistor.

[0023] The power supply terminal of the second operational amplifier is connected to the second power supply, the non-inverting input terminal is connected to the first terminal of the capacitor, the inverting input terminal is connected to the first terminal of the first voltage dividing resistor and the first terminal of the second voltage dividing resistor respectively, the output terminal is connected to the second terminal of the first voltage dividing resistor and the first input terminal of the source follower respectively, and the second terminal of the second voltage dividing resistor is grounded.

[0024] Preferably, the source follower includes a driving module, a first switch and a second switch.

[0025] The input terminal of the driving module is connected to the first terminal of the capacitor, the power supply terminal is connected to the second power supply, the first output terminal is connected to the control terminal of the first switch, the second output terminal is connected to the control terminal of the second switch, the first terminal of the first switch is connected to the second power supply, the second terminal is connected to the first terminal of the second switch, the second terminal of the second switch is connected to the third power supply, and the second terminal of the first switch serves as the output terminal of the source follower.

[0026] The driving module is used for controlling the first switch to be off, the second switch to be on when the voltage of the first end of the capacitor is less than a first threshold voltage, so that the source follower outputs a signal consistent with the variation trend of the third power supply; controlling the first switch to be on, the second switch to be on when the voltage of the first end of the capacitor is greater than the first threshold voltage and less than a second threshold voltage, so that the source follower outputs a signal consistent with the variation trend of the voltage of the first end of the capacitor; controlling the first switch to be on, the second switch to be off when the voltage of the first end of the capacitor is greater than the second threshold voltage, so that the source follower outputs a signal consistent with the variation trend of the voltage of the first end of the capacitor; and the first threshold voltage is less than the second threshold voltage.

[0027] Preferably, the driving module comprises a first current source, a second current source, a first driving switch and a second driving switch.

[0028] The control end of the first driving switch and the control end of the second driving switch are connected with the first end of the capacitor respectively, the first end of the first driving switch is connected with the first end of the first current source, the second end is connected with the second power supply and the first end of the second current source respectively, the second end of the second current source is connected with the first end of the second driving switch, the second end of the second driving switch and the second end of the first current source are grounded, the first end of the second driving switch is used as the first output end of the driving module, and the first end of the first driving switch is used as the second output end of the driving module.

[0029] To solve the above technical problems, the application further provides an electronic control unit applied to a vehicle controller, which comprises a data receiving module and the synchronous pulse generating circuit.

[0030] The application provides a synchronous pulse generation circuit applied to an electronic control unit in a vehicle controller, comprising a control module, a capacitor and a source follower; the control module controls the charging and discharging process of the capacitor based on a starting signal and the voltage of the first end of the capacitor, so that the first end of the capacitor outputs a preset pulse signal; the source follower outputs a follow-up signal consistent with the voltage change trend of the first end of the capacitor based on the preset pulse signal output by the first end of the capacitor when the voltage of the first end of the capacitor meets the follow-up condition, and outputs a voltage signal corresponding to the third power supply when the voltage of the first end of the capacitor does not meet the follow-up condition, so that the synchronous pulse signal output by the whole generation circuit is generated based on the output signal of the first end of the capacitor and the third power supply, and will not change with the change of the sensor load at the rear end; under the premise of consistent parameters, the rising edge and falling edge rate of the synchronous pulse signal are stable, and the rising edge and falling edge rate of the synchronous pulse signal can be controlled by adjusting the parameters of specific devices in the circuit, the output signal is stable and controllable, which is beneficial to the accurate realization of the control process of the ECU on the sensor, and improves the safety and reliability of the vehicle controller.

[0031] The application also provides an electronic control unit having the same beneficial effects as the above-mentioned synchronous pulse generation circuit. BRIEF DESCRIPTION OF DRAWINGS

[0032] In order to more clearly illustrate the technical solutions in the embodiments of the application, the following will briefly introduce the drawings needed to be used in the prior art and embodiments. Obviously, the drawings in the following description are only some embodiments of the application, and other drawings can also be obtained by those skilled in the art without creative effort on the basis of these drawings.

[0033] Figure 1 A structural schematic diagram of a synchronous pulse generation circuit provided by the application;

[0034] Figure 2 A structural schematic diagram of another synchronous pulse generation circuit provided by the application;

[0035] Figure 3 A structural schematic diagram of a reference voltage generation circuit in a synchronous pulse generation circuit provided by the application;

[0036] Figure 4 A structural schematic diagram of a comparison module in a synchronous pulse generation circuit provided by the application;

[0037] Figure 5 A structural schematic diagram of a driving module in a synchronous pulse generation circuit provided by the application;

[0038] Figure 6A signal waveform schematic diagram output by a synchronous pulse generation circuit provided by the present application is shown in the figure;

[0039] Figure 7 A structure schematic diagram of an electronic control unit provided by the present application is shown in the figure. DETAILED DESCRIPTION

[0040] The core of the present application is to provide a synchronous pulse generation circuit and an electronic control unit, the synchronous pulse signal output by the whole generation circuit is generated based on the output signal of the first end of the capacitor and the third power supply, and will not change with the change of the sensor load at the rear end, under the premise of consistent parameters, the rising edge and falling edge rate of the synchronous pulse signal is stable, and the rising edge and falling edge rate of the synchronous pulse signal can be controlled by adjusting the parameters of the specific devices in the circuit, the output signal is stable and controllable, which is conducive to the accurate realization of the control process of the ECU to the sensor, and improves the safety and reliability of the automobile controller.

[0041] In order to make the purpose, technical scheme and advantages of the embodiments of the present application clearer, the technical scheme in the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor are within the scope of protection of the present application.

[0042] The present application provides a synchronous pulse generation circuit mainly applied to an electronic control unit in an automobile controller, which can be used in the control process between the ECU and each sensor, and the type of automobile applied by the automobile controller and other environments are not particularly limited in the present application, and the type of automobile controller and electronic control unit and the specific implementation mode are not particularly limited in the present application. The specific implementation mode is described below.

[0043] Please refer to Figure 1 , Figure 1 A structure schematic diagram of a synchronous pulse generation circuit provided by the present application is shown in the figure;

[0044] Please refer to Figure 2 , Figure 2 A structure schematic diagram of another synchronous pulse generation circuit provided by the present application is shown in the figure, wherein VREFH represents a first reference voltage, VREFL represents a second reference voltage, SYNC_START represents a start signal, SYNCP represents a signal of the first end of the capacitor, VDD represents a first power supply, VDD_HV represents a second power supply, and VDD_MV represents a third power supply;

[0045] To solve the above technical problems, the application provides a synchronous pulse generation circuit, which is applied to an electronic control unit in an automobile controller and comprises a control module 1, a capacitor C1 and a source follower 2.

[0046] A first input end of the control module 1 is connected to a start signal, a second input end is connected to a first reference voltage, a third input end is connected to a first power supply, a fourth input end is connected to a second reference voltage, a first end of the capacitor C1 is connected to a fifth input end of the control module 1, an output end of the control module 1 and a first input end of the source follower 2 respectively, a second end is grounded, a second input end of the source follower 2 is connected to a second power supply, a third input end is connected to a third power supply, and an output end serves as an output end of the synchronous pulse generation circuit.

[0047] The control module 1 is used for charging the capacitor C1 when the start signal is detected and the voltage at the first end of the capacitor C1 is less than the first reference voltage, discharging the capacitor C1 when the voltage at the first end of the capacitor C1 is greater than the first reference voltage after the capacitor C1 is charged, and maintaining the voltage at the first end of the capacitor C1 at the second reference voltage when the start signal is not detected or the capacitor C1 is discharged to the second reference voltage; the second power supply is greater than the third power supply, the third power supply is greater than the first power supply; and the first reference voltage is greater than the second reference voltage.

[0048] The source follower 2 is used for outputting a signal consistent with the voltage change trend at the first end of the capacitor C1 when the voltage at the first end of the capacitor C1 meets a following condition, and outputting a signal consistent with the voltage change trend of the third power supply when the voltage at the first end of the capacitor C1 does not meet the following condition.

[0049] Specifically, in a default state, the start signal is a low-level signal, at this time, the control module 1 does not detect the start signal, and the voltage at the first end of the capacitor C1 is maintained at the second reference voltage; when the electronic control unit in the automobile controller needs to send a synchronous pulse signal to a sensor, the start signal jumps from a low level to a high level, at this time, the control module 1 detects the start signal and starts charging the capacitor C1, the voltage at the first end of the capacitor C1 gradually increases from the second reference voltage, until the first reference voltage is reached, the control module 1 stops charging the capacitor C1 and enters a discharging process, the voltage at the first end of the capacitor C1 gradually decreases from the first reference voltage, until the second reference voltage is reached, the control module 1 maintains the voltage at the first end of the capacitor C1 at the second reference voltage, until the start signal jumps from a low level to a high level again, and the charging and discharging process of the capacitor C1 is repeated, so that the output signal at the first end of the capacitor C1 is a preset synchronous pulse signal, and the rising and falling edges of the preset synchronous pulse signal output by the first end of the capacitor C1 are stable under the condition that the parameters are consistent;

[0050] It can be understood that the source follower 2 outputs a signal consistent with the voltage change trend of the first end of the capacitor C1 when the following condition is met, and outputs a signal consistent with the third power supply change trend when the voltage at the first end of the capacitor C1 does not meet the following condition, thereby outputting a synchronization pulse signal corresponding to the output signal of the first end of the capacitor C1, and the output signal is generated according to the output signal of the first end of the capacitor C1 and the third power supply, and only changes with the changes of the output signal of the first end of the capacitor C1 and the third power supply, and is not affected by the sensor load at the back end.

[0051] It should be noted that the change trend consistent means that the change relationship and phase between the two signals are consistent, and the signal output by the source follower 2 consistent with the voltage change trend of the first end of the capacitor C1 will increase with the increase of the output signal of the first end of the capacitor C1, and decrease with the decrease of the output signal of the first end of the capacitor C1. The slopes of the rising and falling edges of the signal are basically consistent, and the amplitudes will be different due to the existence of the second power supply and the third power supply, but the basic change relationship is basically the same; the signal output by the source follower 2 consistent with the third power supply change trend is also similar, and the third power supply is generally a constant voltage power supply with stable output, so the signal consistent with the third power supply change trend is also a constant voltage output.

[0052] Specifically, the start signal can be preset in advance in the automobile controller, or can be artificially controlled according to the demand in actual application. There is no special requirement for the duration of the high level of the start signal. It can be consistent with a charge and discharge period of the capacitor C1, or it can be inconsistent. It can be set according to actual demand or application environment. The setting method and specific implementation mode of the start signal are not particularly limited in the present application.

[0053] It can be understood that the first power supply, the second power supply and the third power supply can be realized by directly connecting an external power supply, or can be realized by other ways. The size relationship follows the second power supply is greater than the third power supply, and the third power supply is greater than the first power supply. As a specific embodiment, the power supply voltage of the first power supply can be 5V, the power supply voltage of the second power supply can be 14-36V, and the power supply voltage of the third power supply can be 7V. The specific implementation mode and specific value of the first power supply, the second power supply and the third power supply are not particularly limited in the present application, and can be selected according to the specific implementation circuit in actual application or other application factors.

[0054] It should be noted that the first reference voltage and the second reference voltage can be generated directly by the reference voltage source, or can be generated by other means, and are two stable reference voltages; two reference voltages can be generated directly, or one reference voltage can be generated and the other reference voltage can be obtained by voltage reduction or voltage increase operation; in actual application, the output signal of the first end of the capacitor C1 can be adjusted by adjusting the specific values of the first reference voltage and the second reference voltage, so as to control the maximum voltage and the corresponding amplitude of the preset synchronous pulse signal output by the first end of the capacitor C1; the specific implementation mode and specific value of the first reference voltage and the second reference voltage are not particularly limited in the present application, and can be selected according to the specific implementation circuit or other application factors in actual application.

[0055] Please refer to Figure 3 , Figure 3 The structure diagram of the reference voltage generation circuit in a synchronous pulse generation circuit provided by the present application is shown in the figure. Figure 3 A specific implementation mode for obtaining the first reference voltage and the second reference voltage is shown in the figure, the second reference voltage VREFL can be generated by the reference voltage source first, since the first reference voltage is greater than the second reference voltage, the second reference voltage VREFL can be boosted by the third operational amplifier OP3, the third voltage dividing resistor R3 and the fourth voltage dividing resistor R4 to obtain the first reference voltage VREFH.

[0056] Specifically, there are multiple ways to choose the specific implementation circuit of the control module 1, the charging and discharging process of the capacitor C1 can be realized by a current source, or other means, the detection mode of the start signal and the comparison process of the voltage at the first end of the capacitor C1 can be realized by a comparator or other circuit, and the rising edge and falling edge rate of the preset synchronous pulse signal output by the first end of the capacitor C1 can be controlled and adjusted by adjusting the parameters of the specific components in the control module 1; the implementation mode and specific circuit of the control module 1 are not particularly limited in the present application, and there are multiple ways to choose, which can be considered from the cost or actual application environment.

[0057] It can be understood that the specific implementation structure of the source follower 2 also has multiple selection modes, which can be realized by multiple MOS (Metal-Oxide-Semiconductor) tubes, or realized by the combination of MOS tubes and resistors. Considering that other modules in the ECU need to work, and the equivalent resistance of the modules will cause a certain voltage drop, the minimum value of the signal output by the source follower 2 through the third power supply also has a certain voltage, which avoids the situation that the ECU cannot work normally due to too low voltage. The implementation mode and specific circuit of the source follower 2 are not particularly limited in the present application, and multiple selection modes can be considered from aspects such as cost and actual application environment.

[0058] It should be noted that there are multiple determination modes for whether the voltage at the first end of the capacitor C1 meets the following condition. If the source follower 2 adopts the MOS tube implementation mode, the size relationship between the threshold voltage of the MOS tube adopted and the output signal of the voltage at the first end of the capacitor C1 can be used for judgment. Only the final output signal is consistent with the change trend of the voltage at the first end of the capacitor C1, that is, the synchronous pulse signal is basically consistent with the change trend of the output signal of the first end of the capacitor C1, and the minimum voltage amplitude is kept at the third power supply. The specific determination mode of whether the voltage at the first end of the capacitor C1 meets the following condition is not particularly limited in the present application.

[0059] The present application provides a synchronous pulse generation circuit applied to an electronic control unit in a vehicle controller, which comprises a control module 1, a capacitor C1 and a source follower 2. The control module 1 controls the charging and discharging process of the capacitor C1 based on a start signal and the voltage at the first end of the capacitor C1, so that the first end of the capacitor C1 outputs a preset pulse signal. The source follower 2 outputs a following signal consistent with the change trend of the voltage at the first end of the capacitor C1 based on the preset pulse signal output by the first end of the capacitor C1 when the voltage at the first end of the capacitor C1 meets the following condition, and outputs a voltage signal corresponding to the third power supply when the voltage at the first end of the capacitor C1 does not meet the following condition. The synchronous pulse signal output by the entire generation circuit is generated based on the output signal of the first end of the capacitor C1 and the third power supply, and will not change with the change of the sensor load at the rear end. On the premise that the parameters are consistent, the rising edge and falling edge rates of the synchronous pulse signal are stable, and the rising edge and falling edge rates of the synchronous pulse signal can be controlled by adjusting the parameters of the specific devices in the circuit. The output signal is stable and controllable, which is conducive to the accurate implementation of the control process of the ECU on the sensor, and improves the safety and reliability of the vehicle controller.

[0060] On the basis of the above embodiment,

[0061] As a preferred embodiment, the control module 1 comprises a comparison module, a charging module and a discharging module;

[0062] The first input terminal of the comparison module is connected to a first reference voltage, the second input terminal is connected to the first terminal of the capacitor C1, the enable terminal is connected to the start signal, and the output terminals are respectively connected to the control terminals of the charging module and the discharging module. The input terminal of the charging module is connected to a first power supply, and the output terminal is connected to the first terminal of the capacitor C1. The first input terminal of the discharging module is connected to a second reference voltage, and the output terminal is connected to the first terminal of the capacitor C1.

[0063] The comparison module is used to control the discharging module to be turned off when the start signal is detected and the voltage at the first terminal of the capacitor C1 is less than the first reference voltage, and the charging module is turned on to charge the capacitor C1. When the voltage at the first terminal of the capacitor C1 is greater than the first reference voltage after the capacitor C1 is charged, the charging module is controlled to be turned off, and the discharging module is turned on to discharge the capacitor C1. When the start signal is not detected or the capacitor C1 is discharged to the second reference voltage, the discharging module is controlled to maintain the voltage at the first terminal of the capacitor C1 at the second reference voltage.

[0064] Specifically, the functions of the control module 1 are realized by the comparison module, the charging module and the discharging module. The detection of the start signal and the comparison between the voltage at the first terminal of the capacitor C1 and the reference voltage are realized by the comparison module. The charging module and the discharging module are controlled based on the detected signal and the comparison result. The charging process of the capacitor C1 is realized by turning on the charging module, and the discharging process of the capacitor C1 and the process of maintaining the minimum voltage are realized by the discharging module.

[0065] It can be understood that the start signal is connected to the enable terminal of the comparison module. When the start signal is at a low level in the initial state, the comparison module does not work, and the default output signal turns off the charging module and turns on the discharging module. When the start signal jumps from a low level to a high level, the comparison module detects the start signal and starts to work, compares the voltage at the first terminal of the capacitor C1 with the first reference voltage, and maintains the minimum voltage at the first terminal of the capacitor C1 at the second reference voltage after the charging of the capacitor C1, so as to control the charging and discharging process of the capacitor C1.

[0066] Specifically, the specific implementation modes of the comparison module, the charging module and the discharging module are not particularly limited in the present application. The comparison module can be realized by a comparator or a circuit. The charging module and the discharging module can realize the charging and discharging process of the capacitor C1 by a current source or other means.

[0067] As a specific embodiment, the function of the control module 1 is realized by the comparison module, the charging module and the discharging module, the detection of the start signal and the comparison between the voltage at the first end of the capacitor C1 and the reference voltage are realized by the comparison module, and the charging and discharging of the capacitor C1 are realized by outputting the control signal based on the detected signal and the comparison result to control the charging module and the discharging module. The whole circuit structure is simple, the circuit structure of the control module 1 is clearer and more explicit, the function of the control module 1 is effectively realized, the accurate control of the control module 1 on the charging and discharging process of the capacitor C1 is ensured, the accurate realization of the synchronous pulse generation circuit is ensured, which is conducive to the accurate realization of the control process of the ECU on the sensor, and the safety and reliability of the automobile controller are improved.

[0068] As a preferred embodiment, the charging module comprises a charging switch S1 and a charging current source I1.

[0069] The input end of the charging current source I1 is connected with the first power supply, the output end is connected with the first end of the charging switch S1, the second end of the charging switch S1 is connected with the first end of the capacitor C1, and the control end of the charging switch S1 is connected with the output end of the comparison module.

[0070] The charging switch S1 is used for conducting based on the control of the comparison module when the start signal is detected and the voltage at the first end of the capacitor C1 is less than the first reference voltage, and is used for turning off based on the control of the comparison module when the capacitor C1 is charged to the voltage at the first end of the capacitor C1 being greater than the first reference voltage or when the start signal is not detected or the capacitor C1 is discharged to the second reference voltage.

[0071] It can be understood that the charging process of the capacitor C1 can be realized by the charging current source I1, and the charging switch S1 is added, the control end of the charging switch S1 is connected with the output end of the comparison module, so that the comparison module controls whether the capacitor C1 enters the charging process by controlling the conduction and turn-off of the charging switch S1, and the type and specific implementation of the charging current source I1 and the charging switch S1 are not particularly limited in the present application, and the charging switch S1 can be realized by a MOS tube or other controllable switching devices.

[0072] Specifically, the charging module is realized by the combination of the charging current source I1 and the charging switch S1, the comparison module controls whether the capacitor C1 enters the charging process by controlling the conduction and turn-off of the charging switch S1, the whole circuit structure is simple, the cost of the adopted components is low, the circuit structure of the charging module is clearer and more explicit, the function of the charging module is effectively realized, the accurate control of the control module 1 on the charging process of the capacitor C1 is ensured, the accurate realization of the synchronous pulse generation circuit is ensured, which is conducive to the accurate realization of the control process of the ECU on the sensor, and the safety and reliability of the automobile controller are improved.

[0073] Please refer to Figure 4 , Figure 4 The structure diagram of a comparison module in a synchronous pulse generation circuit provided by the application is shown in the figure;

[0074] As a preferred embodiment, the comparison module comprises a comparator COMP and a flip-flop;

[0075] The first input end of the comparator COMP is connected to a first reference voltage, the second input end is connected to the first end of a capacitor C1, the enable end is connected to an enabling signal, and the output end is connected to the first input end of the flip-flop. The second input end of the flip-flop is connected to a first power supply, the set end is connected to the enabling signal, and the output end is connected to the control end of a charging module and the control end of a discharging module, respectively.

[0076] The flip-flop is used to output a low level based on the low level output by the comparator COMP when the enabling signal is detected and the voltage at the first end of the capacitor C1 is less than the first reference voltage, so as to control the discharging module to be turned off and the charging module to be turned on to charge the capacitor C1. When the capacitor C1 is charged to a voltage at the first end of the capacitor C1 greater than the first reference voltage, the flip-flop is controlled to output a high level based on the high level output by the comparator COMP, so as to control the charging module to be turned off and the discharging module to be turned on to discharge the capacitor C1. When the enabling signal is not detected or the capacitor C1 is discharged to a second reference voltage, the flip-flop is controlled to output a high level based on the high level output by the comparator COMP, so as to control the discharging module to maintain the voltage at the first end of the capacitor C1 at the second reference voltage.

[0077] It can be understood that the main function of the comparison module is realized by the comparator COMP, and the flip-flop is combined with the comparator COMP to realize the comparison module considering the possible oscillation in the charging process. The enabling signal is connected to the enable end of the comparator COMP. When the enabling signal is at a low level in the initial state, the comparator COMP does not work and outputs a high level by default, and the flip-flop also outputs a high level, so that the charging module is turned off and the discharging module is turned on. When the enabling signal jumps from a low level to a high level, the comparator COMP detects the enabling signal and starts to work to compare the voltage at the first end of the capacitor C1 with the first reference voltage. When the voltage at the first end of the capacitor C1 is less than the first reference voltage, the comparator COMP and the flip-flop output a low level to perform the charging process of the capacitor C1. When the capacitor C1 is charged to a voltage at the first end of the capacitor C1 greater than the first reference voltage, the comparator COMP and the flip-flop output a high level to turn off the charging module and enter the discharging process of the capacitor C1, and the discharging module is turned on to maintain the voltage at the first end of the capacitor C1 at the second reference voltage.

[0078] In the figure, Figure 4For example, in order to ensure that the first end SYNCP of the capacitor C1 does not oscillate after being charged to the first reference voltage VREFH, the output signal of the comparator COMP needs to be processed. By means of the combination of the comparator COMP and the D flip-flop D1, the start signal SYNC_START is connected to the enable end of the comparator COMP and the SET end of the D flip-flop, respectively. When the start signal SYNC_START is at a low level, the comparator COMP does not work and the output is "1", and the D flip-flop D1 outputs "1". When the start signal SYNC_START switches from a low level to a high level, the comparator COMP normally works, the output switches from a high level to a low level, and the D flip-flop D1 outputs "0". When the voltage of the first end SYNCP of the capacitor C1 reaches the first reference voltage VREFH, the output of the comparator COMP switches from a low level to a high level, the output of the D flip-flop D1 becomes "1", and the output end Q of the D flip-flop is used as the output end of the comparison module.

[0079] Specifically, the types and specific implementation modes of the comparator COMP and the flip-flop are not particularly limited in the present application. The flip-flop can be a D flip-flop or other types, and can be selected and adjusted according to the actual application environment and the specific implementation circuit. The comparison module can also be directly realized by a comparator. The specific implementation mode of the comparison module is not particularly limited in the present application.

[0080] The comparison module is realized by means of the combination of the comparator COMP and the flip-flop. The comparison function of the comparison module is mainly realized by the comparator COMP. The start signal is connected to the comparator COMP and the flip-flop, which ensures the accurate control of the start signal on the charging and discharging process of the capacitor C1. The flip-flop is connected to the comparator COMP, which makes the control signal output by the comparison module more stable and improves the anti-interference ability of the control signal. This is conducive to the accurate realization of the charging and discharging process of the capacitor C1. The whole circuit structure is simple, the components used are easy to realize, the circuit structure of the comparison module is clear and explicit, the function of the comparison module is effectively realized, the accurate control of the control module 1 on the charging and discharging process of the capacitor C1 is further ensured, and the accurate realization of the synchronous pulse generation circuit is ensured.

[0081] As a preferred embodiment, the discharging module comprises a first operational amplifier OP1, a discharging switch S2 and a discharging current source I2.

[0082] The non-inverting input terminal of the first operational amplifier OP1 is connected to the second reference voltage, the inverting input terminal is connected to the output terminal of the first operational amplifier OP1, and the output terminal of the first operational amplifier OP1 is also connected to the first terminal of the discharge current source I2; the second terminal of the discharge current source I2 is connected to the first terminal of the discharge switch S2, the second terminal of the discharge switch S2 is connected to the first terminal of the capacitor C1, and the control terminal is connected to the output terminal of the comparison module.

[0083] The discharge switch S2 is used for being turned off based on the control of the comparison module when the start signal is detected and the voltage at the first terminal of the capacitor C1 is less than the first reference voltage, being turned on based on the control of the comparison module when the capacitor C1 is charged to the voltage at the first terminal of the capacitor C1 being greater than the first reference voltage, and being turned on based on the control of the comparison module when the start signal is not detected or the capacitor C1 is discharged to the second reference voltage.

[0084] It can be understood that the discharge process of the capacitor C1 can be realized by the discharge current source I2, and the discharge switch S2 is added, the control terminal of the discharge switch S2 is connected to the output terminal of the comparison module, so that the comparison module controls whether the capacitor C1 enters the discharge process by controlling the turn-on and turn-off of the discharge switch S2, and the discharge current source I2 is connected to the second reference voltage through the first operational amplifier OP1, so that the discharge process of the capacitor C1 stops when the capacitor C1 is discharged to the second reference voltage; in the default state in which the comparison module does not work, the first terminal of the capacitor C1 is also connected to the output terminal of the first operational amplifier OP1 through the turned-on discharge switch S2, and the signal output by the first operational amplifier OP1 is basically consistent with the second reference voltage, which plays a role in enhancing the driving and stabilizing the signal, so that the minimum amplitude of the voltage at the first terminal of the capacitor C1 is maintained at the second reference voltage. The types and specific implementation manners of the first operational amplifier OP1, the discharge current source I2 and the discharge switch S2 are not particularly limited in the present application, and the discharge switch S2 can be realized by a MOS tube or other controllable switching devices.

[0085] Specifically, the discharge module is realized by the combination of the first operational amplifier OP1, the discharge current source I2 and the discharge switch S2, the comparison module controls whether the capacitor C1 enters the discharge process and maintains the minimum amplitude of the voltage at the first terminal of the capacitor C1 at the second reference voltage by controlling the turn-on and turn-off of the discharge switch S2, the circuit structure is simple, the cost of the components used is low, the circuit structure of the discharge module is clearer and more explicit, the function of the discharge module is effectively realized, the control module 1 directly cooperates with the comparison module to ensure the accurate control of the control module 1 on the discharge process of the capacitor C1, the accurate realization of the generation circuit of the synchronous pulse is ensured, which is conducive to the accurate realization of the control process of the ECU on the sensor and improves the safety and reliability of the automobile controller.

[0086] As a preferred embodiment, the voltage boosting module is further included;

[0087] The first input end of the voltage boosting module is connected with the first end of the capacitor C1, and the output end is connected with the first input end of the source follower 2.

[0088] In actual application, the capacity of the capacitor C1 used is small, the voltage required by the power supply or device used in the control module 1 is low, the voltage of the preset synchronization pulse signal output from the first end of the capacitor C1 is small, the source follower 2 is difficult to realize, and the finally output signal may not meet the effective control of the sensor, so the voltage boosting module is added between the capacitor C1 and the source follower 2, the signal at the first end of the capacitor C1 is boosted, which plays a role of signal amplification, and outputs a synchronization pulse signal with increased voltage amplitude corresponding to the preset synchronization pulse signal. The synchronization pulse signal after voltage boosting is basically consistent with the synchronization pulse signal at the first end of the capacitor C1 in terms of voltage amplitude and change trend, etc. Specifically, the specific type and implementation of the voltage boosting module are not particularly limited in the present application, and can be realized by a voltage dividing circuit or other ways.

[0089] When the voltage of the preset synchronization pulse signal output from the first end of the capacitor C1 is small, it is not conducive to the realization of the subsequent control process, the voltage boosting module is added between the capacitor C1 and the source follower 2 to amplify the signal, and the higher voltage is conducive to the accurate realization of the source follower 2, and at the same time, the voltage of the finally output synchronization pulse signal can meet the control requirements of the rear sensor, which is conducive to the accurate realization of the control process of the sensor by the ECU, and improves the safety and reliability of the automobile controller

[0090] As a preferred embodiment, the voltage boosting module includes a second operational amplifier OP2, a first voltage dividing resistor R1 and a second voltage dividing resistor R2.

[0091] The power supply end of the second operational amplifier OP2 is connected with the second power supply, the same-phase input end is connected with the first end of the capacitor C1, the opposite-phase input end is respectively connected with the first end of the first voltage dividing resistor R1 and the first end of the second voltage dividing resistor R2, the output end is respectively connected with the second end of the first voltage dividing resistor R1 and the first input end of the source follower 2, and the second end of the second voltage dividing resistor R2 is grounded.

[0092] Specifically, the function of the voltage boosting module can be realized by the cooperation of the second operational amplifier OP2, the first voltage dividing resistor R1 and the second voltage dividing resistor R2. The signal at the first end of the capacitor C1 is amplified by using the principle of the voltage dividing circuit and cooperating with the operational amplifier. The specific type, implementation manner and specific value of the second operational amplifier OP2, the first voltage dividing resistor R1 and the second voltage dividing resistor R2 are not particularly limited in the present application. The voltage boosting multiple can be adjusted by adjusting the resistance values of the first voltage dividing resistor R1 and the second voltage dividing resistor R2. In general, the appropriate second operational amplifier OP2, the first voltage dividing resistor R1 and the second voltage dividing resistor R2 are selected according to the requirements of the rear-end sensor in the actual application and the voltage drop requirements of other modules in the ECU.

[0093] The function of the voltage boosting module is realized by the cooperation of the second operational amplifier OP2, the first voltage dividing resistor R1 and the second voltage dividing resistor R2. The whole circuit structure is simple, the adopted components are easy to realize, the circuit structure of the voltage boosting module is clearer and more explicit, the function of the voltage boosting module is effectively realized, the accurate realization of the synchronous pulse generation circuit is ensured, which is conducive to the accurate realization of the control process of the ECU on the sensor and improves the safety and reliability of the automobile controller.

[0094] As a preferred embodiment, the source follower 2 includes a driving module DRV, a first switch NM1 and a second switch PM1.

[0095] The input end of the driving module DRV is connected with the first end of the capacitor C1, the power supply end is connected with the second power supply, the first output end is connected with the control end of the first switch NM1, the second output end is connected with the control end of the second switch PM1, the first end of the first switch NM1 is connected with the second power supply, the second end is connected with the first end of the second switch PM1, the second end of the second switch PM1 is connected with the third power supply, and the second end of the first switch NM1 serves as the output end of the source follower 2.

[0096] The driving module DRV is configured to control the first switch NM1 to be turned off and the second switch PM1 to be turned on when the voltage at the first end of the capacitor C1 is less than a first threshold voltage, so that the source follower 2 outputs a signal consistent with the change trend of the third power supply; control the first switch NM1 to be turned on and the second switch PM1 to be turned on when the voltage at the first end of the capacitor C1 is greater than the first threshold voltage and less than a second threshold voltage, so that the source follower 2 outputs a signal consistent with the change trend of the voltage at the first end of the capacitor C1; control the first switch NM1 to be turned on and the second switch PM1 to be turned off when the voltage at the first end of the capacitor C1 is greater than the second threshold voltage, so that the source follower 2 outputs a signal consistent with the change trend of the voltage at the first end of the capacitor C1; and the first threshold voltage is less than the second threshold voltage.

[0097] Specifically, the source follower 2 is realized by two switch tubes of the first switch NM1 and the second switch PM1, and considering the control process of the two switches, the driving module DRV is added, which divides the output signal of the first end of the capacitor C1 into two control signals to control the first switch NM1 and the second switch PM1 respectively, and at the same time, the determination module is between the capacitor C1 and the two switch tubes, which also plays a role of a buffer circuit, preventing the signal at the first end of the capacitor C1 from being disturbed due to the turn-on or turn-off process of the switch tubes, and causing the signal at the first end of the capacitor C1 to change; correspondingly, whether the voltage at the first end of the capacitor C1 meets the following condition depends on the threshold voltage for turn-on of the first switch NM1 and the second switch PM1.

[0098] It can be understood that the first threshold voltage is the threshold voltage corresponding to the turn-on of the first switch NM1, and the second threshold voltage is the threshold voltage corresponding to the turn-off of the second switch PM1, and the first switch NM1 can be selected as an N-type MOS tube, and the second switch PM1 can be selected as a P-type MOS tube, and the turn-on and turn-off of the two are controlled according to the voltage size of the first end of the capacitor C1, and the type and specific implementation manner of the first switch NM1 and the second switch PM1 are not particularly limited in the present application, and can be adjusted according to actual needs.

[0099] As a specific implementation manner of the source follower 2, the function of the source follower 2 is realized by the combination of the driving module DRV, the first switch NM1 and the second switch PM1, and correspondingly, whether the voltage at the first end of the capacitor C1 meets the following condition is also determined by the threshold voltage of the first switch NM1 and the second switch PM1, the whole circuit structure is simple, the adopted components are easy to realize, the circuit structure of the source follower 2 is clearer and more explicit, the function of the source follower 2 is effectively realized, the accurate output of the source follower 2 for the synchronous pulse signal is ensured, the accurate realization of the synchronous pulse generation circuit is ensured, which is conducive to the accurate realization of the subsequent ECU for the control process of the sensor, and improves the safety and reliability of the automobile controller.

[0100] Please refer to Figure 5 , Figure 5 for a structure diagram of a driving module in a synchronous pulse generation circuit provided by the present application;

[0101] As a preferred embodiment, the driving module DRV includes a first current source I3, a second current source I4, a first driving switch NM2 and a second driving switch PM2.

[0102] The control end of the first drive switch NM2 and the control end of the second drive switch PM2 are connected with the first end of the capacitor C1 respectively, the first end of the first drive switch NM2 is connected with the first end of the first current source I3, the second end is connected with the second power supply and the first end of the second current source I4 respectively, the second end of the second current source I4 is connected with the first end of the second drive switch PM2, the second end of the second drive switch PM2 and the second end of the first current source I3 are grounded, the first end of the second drive switch PM2 is the first output end of the drive module DRV, and the first end of the first drive switch NM2 is the second output end of the drive module DRV.

[0103] Specifically, the drive module DRV is realized by the first current source I3, the second current source I4, the first drive switch NM2 and the second drive switch PM2, and one received signal is converted into two output signals by two drive switches and corresponding current sources, so that the subsequent control process of the drive module DRV on the first switch NM1 and the second switch PM1, the type and specific implementation mode of the first current source I3, the second current source I4, the first drive switch NM2 and the second drive switch PM2, etc. are not particularly limited in this application. Figure 5 For example, Figure 5 The first output end connected with the control end of the first switch NM1 is represented as TO NM1, and the second output end connected with the control end of the second switch PM1 is represented as TO PM1.

[0104] As a specific embodiment, the drive module DRV can be realized by the first current source I3, the second current source I4, the first drive switch NM2 and the second drive switch PM2, the whole circuit structure is simple, the adopted components are easy to realize, the circuit structure of the drive module DRV is clearer and more explicit, the function of the drive module DRV is effectively realized, the accurate control of the drive module DRV on the first switch NM1 and the second switch PM1 is ensured, the accurate realization of the synchronous pulse generation circuit is ensured, which is conducive to the accurate realization of the control process of the ECU on the sensor, and improves the safety and reliability of the automobile controller.

[0105] For example, Figure 2For example, the control module 1 is implemented through comparator COMP, first operational amplifier OP1, charging current source I1, charging switch S1, discharging current source I2 and discharging switch S2; the drive module DRV, first switch NM1 and second switch PM1 are implemented as source follower 2; the second operational amplifier OP2, first voltage divider resistor R1 and second voltage divider resistor R2 are implemented as boost module; Req represents the equivalent resistance of other modules in the electronic control unit; cload and iload represent the equivalent modules of the sensor load; VDD supplies power to comparator COMP and first operational amplifier OP1; VDD_HV supplies power to second operational amplifier OP2, drive module DRV and first switch NM1; VDD_MV supplies power to second switch PM1; and VCE is connected to the external sensor.

[0106] Please refer to Figure 6 , Figure 6 A schematic diagram of the signal waveform output by a synchronization pulse generation circuit provided by the present invention; Figure 6 Therefore Figure 2 The following is a schematic diagram of the waveforms of signals at various positions during the operation of a synchronization pulse generation circuit, for example. SYNC_START represents the start signal, SYNCP represents the signal at the first end of capacitor C1, COMP_OUT represents the output signal of the comparator module, SYNCP_HV represents the signal after SYNCP boost, and VCE represents the synchronization pulse signal finally output by the electronic control unit.

[0107] like Figure 6 As shown, when the start signal SYNC_START is low, the comparator COMP does not work, and the output signal COMP_OUT is high, controlling the charging switch S1 to open, turning off the charging current source I1, and the discharging switch S2 to close, turning on the discharging current source I2 so that the voltage of the first terminal SYNCP of capacitor C1 is maintained at the second reference voltage VREFL. At this time, the first switch NM1 is open, the second switch PM1 is on, and the output VCE voltage will be maintained at VDD_MV-i load*Req, providing power to the sensor.

[0108] When the start signal SYNC_START is high, the comparator COMP works normally. Since the voltage of the first end SYNCP of the capacitor C1 is less than the first reference voltage VREFH at this time, the output signal COMP_OUT of the comparator COMP is low. At this time, the control discharging switch S2 is opened, the charging current source I2 is turned off, the charging switch S1 is closed, and the charging current source I1 is turned on to charge the first end SYNCP of the capacitor C1. When the voltage of the first end SYNCP of the capacitor C1 exceeds the first reference voltage VREFH, the output signal COMP_OUT of the comparator COMP becomes high, the charging switch S1 is opened, the discharging switch S2 is closed, and the first end SYNCP of the capacitor C1 starts to discharge until the voltage reaches the second reference voltage VREFL. The rising edge and the falling edge of the SYNCP signal can be controlled by setting the current of the charging current source I1 and the discharging current source I2 and the capacitance of the capacitor C1. During the process of charging the voltage of the first end SYNCP of the capacitor C1 from the second reference voltage VREFL to the first reference voltage VREFH, when the voltage of SYNCP_HV approaches the voltage of VDD_MV, the second switch PM1 tends to be closed, and the first switch NM1 tends to be turned on. At this time, the output VCE voltage will rise with the voltage of SYNCP_HV. Similarly, during the process of discharging the voltage of SYNCP from the first reference voltage VREFH to the second reference voltage VREFL, the output VCE voltage will also decrease with the voltage of SYNCP_HV until the voltage of SYNCP_HV approaches the voltage of VDD_MV. At this time, the first switch NM1 tends to be closed, and the second switch PM1 tends to be turned on. The VCE voltage returns to the voltage of VDD_MV-i load*Req. As described above, the output VCE voltage can basically follow the voltage of SYNCP_HV in real time, and the synchronous pulse does not change with the load. In addition, due to the filtering effect of the equivalent resistance Req and Cload, the top of the output VCE synchronous pulse signal will change slowly, reducing the EMC (Electromagnetic Compatibility) interference of the signal. Generally, the high level duration of the start signal SYNC_START should be greater than the time of charging the capacitor C1 to the voltage of VREFH, so that the capacitor C1 can be fully charged.

[0109] Please refer to Figure 7 , Figure 7 a structure schematic diagram of an electronic control unit provided by the present application;

[0110] To solve the above technical problems, the application further provides an electronic control unit applied to the automobile controller, the electronic control unit comprising a data receiving module 22 and the synchronization pulse generating circuit 21 as described above, the data receiving module 22 being connected with the synchronization pulse generating circuit 21.

[0111] It can be understood that the automobile controller comprises but is not limited to the electronic control unit as described above, and can comprise other functional modules, and the electronic control unit is not limited to the data receiving module 22 and the synchronization pulse generating circuit 21 as described above, and the type and specific implementation mode of the automobile controller and the electronic control unit are not particularly limited herein.

[0112] Specifically, the internal structure and specific implementation mode of the data receiving module 22 are not particularly limited herein, and the connection mode between the data receiving module 22 and the synchronization pulse generating circuit 21 can also be selected in multiple modes, which are not particularly limited herein.

[0113] The electronic control unit provided by the application is introduced in the above embodiment of the synchronization pulse generating circuit, and will not be described herein again.

[0114] It should be further noted that, in the present specification, the relationship terms such as first and second are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply that there is any such actual relationship or order between the entities or operations. Moreover, the terms "include", "contain" or any other variants thereof are intended to cover non-exclusive inclusion, so that the process, method, article or device including a series of elements not only includes those elements, but also includes other elements not explicitly listed or inherent to such process, method, article or device. Without more limitation, the element defined by the statement "including a" does not exclude the presence of another identical element in the process, method, article or device including the element.

[0115] The above description of the disclosed embodiments enables a person skilled in the art to implement or use the application. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the application. Therefore, the application will not be limited to the embodiments shown herein, but will conform to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A synchronous pulse generation circuit, characterized by comprising: An electronic control unit applied to a car controller, comprising a control module, a capacitor and a source follower; a first input end of the control module is connected with a start signal, a second input end is connected with a first reference voltage, a third input end is connected with a first power supply, a fourth input end is connected with a second reference voltage, a first end of the capacitor is connected with a fifth input end of the control module, an output end of the control module and a first input end of the source follower, a second end is grounded, a second input end of the source follower is connected with a second power supply, a third input end is connected with a third power supply, and an output end is an output end of a synchronous pulse generation circuit; the control module is used for charging the capacitor when the start signal is detected and a voltage of the first end of the capacitor is less than the first reference voltage, and discharging the capacitor when the voltage of the first end of the capacitor is greater than the first reference voltage; the voltage of the first end of the capacitor is maintained at the second reference voltage when the start signal is not detected or the capacitor is discharged to the second reference voltage; the second power supply is greater than the third power supply, and the third power supply is greater than the first power supply; the first reference voltage is greater than the second reference voltage; the source follower is used for outputting a signal consistent with a voltage change trend of the first end of the capacitor when the voltage of the first end of the capacitor meets a following condition, and outputting a signal consistent with a voltage change trend of the third power supply when the voltage of the first end of the capacitor does not meet the following condition.

2. The synchronized pulse generating circuit of claim 1, wherein, the control module comprises a comparison module, a charging module and a discharging module; a first input end of the comparison module is connected with a first reference voltage, a second input end is connected with the first end of the capacitor, an enable end is connected with a start signal, and an output end is connected with a control end of the charging module and a control end of the discharging module respectively, an input end of the charging module is connected with a first power supply, and an output end is connected with the first end of the capacitor, a first input end of the discharging module is connected with a second reference voltage, and an output end is connected with the first end of the capacitor; the comparison module is used for controlling the discharging module to be turned off when the start signal is detected and a voltage of the first end of the capacitor is less than the first reference voltage, controlling the charging module to be turned on to charge the capacitor when the voltage of the first end of the capacitor is greater than the first reference voltage, and controlling the charging module to be turned off and the discharging module to be turned on to discharge the capacitor, and controlling the discharging module to maintain the voltage of the first end of the capacitor at the second reference voltage when the start signal is not detected or the capacitor is discharged to the second reference voltage.

3. The synchronized pulse generating circuit of claim 2, wherein, the charging module comprises a charging switch and a charging current source; an input end of the charging current source is connected with a first power supply, and an output end is connected with a first end of the charging switch, a second end of the charging switch is connected with the first end of the capacitor, and a control end of the charging switch is connected with an output end of the comparison module. The charging switch is used for turning on based on the control of the comparison module when the start signal is detected and the voltage of the first end of the capacitor is less than the first reference voltage, turning off based on the control of the comparison module when the capacitor is charged to the voltage of the first end of the capacitor being greater than the first reference voltage, and turning off based on the control of the comparison module when the start signal is not detected or the capacitor is discharged to the second reference voltage.

4. The synchronized pulse generating circuit of claim 2, wherein, The comparison module comprises a comparator and a flip-flop; The first input end of the comparator is connected to a first reference voltage, the second input end is connected to the first end of the capacitor, the enable end is connected to a start signal, the output end is connected to the first input end of the flip-flop, the second input end of the flip-flop is connected to the first power supply, the set end is connected to the start signal, and the output end is connected to the control end of the charging module and the control end of the discharging module respectively. The flip-flop is used for outputting a low level based on the low level output by the comparator to control the discharging module to turn off, the charging module to turn on to charge the capacitor when the start signal is detected and the voltage of the first end of the capacitor is less than the first reference voltage, outputting a high level based on the high level output by the comparator to control the charging module to turn off and the discharging module to turn on to discharge the capacitor when the capacitor is charged to the voltage of the first end of the capacitor being greater than the first reference voltage, and outputting a high level based on the high level output by the comparator to control the discharging module to maintain the voltage of the first end of the capacitor at the second reference voltage when the start signal is not detected or the capacitor is discharged to the second reference voltage.

5. The synchronized pulse generating circuit of claim 2, wherein, The discharging module comprises a first operational amplifier, a discharging switch and a discharging current source. The non-inverting input end of the first operational amplifier is connected to a second reference voltage, the inverting input end is connected to the output end of the first operational amplifier, the output end of the first operational amplifier is also connected to the first end of the discharging current source, the second end of the discharging current source is connected to the first end of the discharging switch, the second end of the discharging switch is connected to the first end of the capacitor, and the control end is connected to the output end of the comparison module. The discharging switch is used for turning off based on the control of the comparison module when the start signal is detected and the voltage of the first end of the capacitor is less than the first reference voltage, turning on based on the control of the comparison module when the capacitor is charged to the voltage of the first end of the capacitor being greater than the first reference voltage, and turning on based on the control of the comparison module when the start signal is not detected or the capacitor is discharged to the second reference voltage.

6. The synchronized pulse generating circuit of claim 1, wherein, The boost module is further included; The first input end of the boost module is connected to the first end of the capacitor, and the output end is connected to the first input end of the source follower.

7. The synchronized pulse generating circuit of claim 6, wherein, The boost module comprises a second operational amplifier, a first voltage dividing resistor and a second voltage dividing resistor. The power supply end of the second operational amplifier is connected with the second power supply, the non-inverting input end is connected with the first end of the capacitor, the inverting input end is connected with the first end of the first voltage dividing resistor and the first end of the second voltage dividing resistor respectively, the output end is connected with the second end of the first voltage dividing resistor and the first input end of the source follower respectively, and the second end of the second voltage dividing resistor is grounded.

8. The synchronized pulse generating circuit of any one of claims 1 to 7, wherein, The source follower comprises a driving module, a first switch and a second switch. The input end of the driving module is connected with the first end of the capacitor, the power supply end is connected with the second power supply, the first output end is connected with the control end of the first switch, the second output end is connected with the control end of the second switch, the first end of the first switch is connected with the second power supply, the second end is connected with the first end of the second switch, the second end of the second switch is connected with the third power supply, and the second end of the first switch serves as the output end of the source follower. The driving module is used for controlling the first switch to be turned off, the second switch to be turned on, so that the source follower outputs a signal consistent with the change trend of the third power supply when the voltage of the first end of the capacitor is less than the first threshold voltage. The driving module is used for controlling the first switch to be turned on, the second switch to be turned on, so that the source follower outputs a signal consistent with the change trend of the voltage of the first end of the capacitor when the voltage of the first end of the capacitor is greater than the first threshold voltage and less than the second threshold voltage; and the driving module is used for controlling the first switch to be turned on, the second switch to be turned off, so that the source follower outputs a signal consistent with the change trend of the voltage of the first end of the capacitor when the voltage of the first end of the capacitor is greater than the second threshold voltage. The first threshold voltage is less than the second threshold voltage.

9. The synchronized pulse generating circuit of claim 8, wherein, The driving module comprises a first current source, a second current source, a first driving switch and a second driving switch. The control end of the first driving switch and the control end of the second driving switch are connected with the first end of the capacitor respectively, the first end of the first driving switch is connected with the first end of the first current source, the second end is connected with the second power supply and the first end of the second current source respectively, the second end of the second current source is connected with the first end of the second driving switch, the second end of the second driving switch and the second end of the first current source are grounded, the first end of the second driving switch serves as the first output end of the driving module, and the first end of the first driving switch serves as the second output end of the driving module.

10. An electronic control unit, characterized by The electronic control unit comprises a data receiving module and the synchronous pulse generation circuit according to any one of claims 1 to 9.

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