Slope control circuit, LIN interface chip and micro-processing chip
By designing a signal output module and a control module on the LIN bus, combining the amplifier module and transistors, dynamically adjusting the signal slope and current, the current instability problem caused by the PVT influence of ordinary current mirror circuits is solved, and stable LIN signal transmission is achieved.
Patent Information
- Application Number
- CN202420931189.5
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-04-30
- Publication Date
- 2024-12-20
- Estimated Expiration
- 2034-04-30
AI Technical Summary
In the prior art, the LIN signal slope control circuit constructed based on ordinary current mirrors is affected by PVT, resulting in unstable current on the chip, which makes the current on the LIN bus too large and cannot obtain an ideal LIN signal.
A slope control circuit including a signal output module and a control module is designed. By outputting an electrical signal corresponding to the preset slope, the signal slope and current value on the LIN bus are adjusted to ensure that the current is within the preset range, and the amplifier module is used and Components such as transistors realize dynamic adjustment, rapid response and noise interference suppression.
It effectively stabilizes the current of the LIN signal, avoids too large or too small current, ensures that a relatively ideal LIN signal is obtained, meets the needs of different reaction speeds and adjustment accuracy, and reduces its impact when noise interference occurs.
Smart Images
Figure CN222215709U_ABST
Abstract
Description
Technical Field
[0001] The present application relates to the technical field of analog circuits, and in particular to a slope control circuit, a LIN interface chip and a microprocessor chip suitable for a LIN bus. Background Art
[0002] LIN bus is a simple, low-cost serial communication, which is widely used in our daily life, such as cars, washing machines, refrigerators, and printers. Usually, LIN bus transmits information between devices through LIN signal (trapezoidal wave signal). Therefore, before applying LIN bus to transmit information between devices, it is necessary to obtain an ideal LIN signal.
[0003] In the prior art, a common current mirror is usually used to directly control the slope corresponding to the LIN signal on the LIN bus, thereby obtaining an ideal LIN signal.
[0004] However, the LIN signal slope control circuit constructed based on the common current mirror is greatly affected by PVT. Therefore, when the LIN signal slope control circuit constructed based on the common current mirror is used to directly control the slope corresponding to the LIN signal on the LIN bus, due to the influence of PVT, the on-chip current of the relevant LIN signal slope control circuit may be unstable, that is, the on-chip current of the LIN signal slope control circuit is too large, which in turn makes the current on the LIN bus too large, and finally makes the determined LIN signal unsatisfactory.
[0005] It should be pointed out that the information disclosed in the background technology section of this application is only intended to deepen the understanding of the general background technology of this application, and should not be regarded as an admission or suggestion in any form that the information constitutes prior art already known to those skilled in the art. Utility Model Content
[0006] In view of this, the present application provides a slope control circuit, a LIN interface chip and a microprocessor chip suitable for a LIN bus, so as to solve the problem in the prior art that due to the influence of PVT, the on-chip current of the related LIN signal slope control circuit is too large, which in turn causes the current on the LIN bus to be too large, and ultimately makes the determined LIN signal unsatisfactory.
[0007] In a first aspect, an embodiment of the present application provides a slope control circuit applicable to a LIN bus, comprising:
[0008] A signal output module, the signal output module is used to output a first electrical signal corresponding to a preset slope;
[0009] A control module, wherein the input end of the control module is electrically connected to the output end of the signal output module, and the output end of the control module is electrically connected to the LIN bus. The control module is used to output a first control signal at the output end of the control module according to the first electrical signal, and the first control signal is used to adjust the slope of the corresponding LIN signal on the LIN bus to a preset slope, and control the corresponding current value of the LIN signal to be a preset current value.
[0010] In the embodiment of the present application, due to the first control signal determined by the control module, in addition to adjusting the slope of the corresponding LIN signal on the LIN bus to a preset slope, the voltage value of the corresponding LIN signal on the LIN bus can also be adjusted to a preset current value. It can be understood that when the current value of the corresponding LIN signal on the LIN bus is too high or too low, the first control signal determined by the control module dynamically adjusts the current value of the LIN signal, so that the current value of the corresponding LIN signal on the LIN bus is the preset current, thereby preventing the current on the LIN bus from being too large or too small, and thus obtaining a relatively ideal LIN signal.
[0011] In a possible implementation, the method further includes:
[0012] an amplifying module, wherein an input end of the amplifying module is electrically connected to an output end of the signal output module, an output end of the amplifying module is electrically connected to an input end of the control module, and the amplifying module is used to amplify the first electrical signal and output a corresponding second electrical signal at the output end of the amplifying module;
[0013] The control module is used for outputting a first control signal at an output end of the control module according to the two voltages.
[0014] In an embodiment of the present application, an amplification module is connected between the signal output module and the control module. The amplification module can amplify the first electrical signal into a second electrical signal and ensure that the waveform of the second electrical signal is consistent with that of the first electrical signal, thereby making the voltage value of the corresponding LIN signal on the LIN bus a preset current, and finally obtaining a more ideal LIN signal.
[0015] In a possible implementation, the signal output module includes:
[0016] A ramp current source, the ramp current source being used to output a corresponding ramp current according to the preset slope;
[0017] A first resistor, wherein a first end of the first resistor is electrically connected to the output end of the ramp current source, and a second end of the first resistor is grounded, wherein the first end of the first resistor is the output end of the signal output module.
[0018] In the embodiment of the present application, the signal output module includes a ramp current source and a first resistor. Specifically, the ramp current source outputs a ramp current corresponding to a preset slope; when the ramp current flows through the first resistor to the ground, a first electrical signal corresponding to the preset slope is generated at the second end of the first resistor. It can be understood that the preset slope is converted into the first electrical signal voltage value through the above transformation, which is more conducive to the control of the current corresponding to the LIN signal, and thus a more ideal LIN signal can be obtained.
[0019] In a possible implementation, the amplification module includes:
[0020] A first amplifier, wherein a non-inverting input terminal of the first amplifier is electrically connected to an output terminal of the signal output module, wherein the non-inverting input terminal of the first amplifier is an input terminal of the amplification module, and an output terminal of the first amplifier is an output terminal of the amplification module;
[0021] a second resistor, wherein a first end of the second resistor is electrically connected to the output end of the first amplifier, and a second end of the second resistor is electrically connected to the inverting input end of the first amplifier;
[0022] A third resistor, wherein a first end of the third resistor is electrically connected to the inverting input end of the first amplifier, and a second end of the third resistor is grounded.
[0023] In the embodiment of the present application, an amplifying module is formed by the first amplifier, the second resistor and the third resistor, so that the output impedance of the amplifying module is low, and the output current of the amplifying module can be effectively controlled, so that a more ideal LIN signal can be obtained.
[0024] In a possible implementation, the control module includes: a first control circuit and a second control circuit, wherein the second control circuit controls the current corresponding to the LIN signal faster than the first control circuit.
[0025] In an embodiment of the present application, the control module includes a first control circuit and a second control circuit. Since the second control circuit controls the current corresponding to the LIN signal faster than the first control circuit, and usually the first control circuit controls the current corresponding to the LIN signal more accurately, the control module can better meet the requirements of different reaction speeds and different adjustment accuracy in combination with specific application scenarios.
[0026] In a possible implementation manner, the first control circuit includes:
[0027] A second amplifier, an inverting input terminal of the second amplifier is electrically connected to the output terminal of the signal output module, wherein the inverting input terminal of the second amplifier is the input terminal of the control module;
[0028] a first transistor, wherein a source of the first transistor is electrically connected to a voltage source, and a gate of the first transistor is electrically connected to an output terminal of the second amplifier;
[0029] a second transistor, wherein a gate of the second transistor is electrically connected to a drain of the first transistor, and a drain of the second transistor is electrically connected to an output end of the LIN bus, wherein the drain of the second transistor is an output end of the control module;
[0030] A fourth resistor, wherein a first end of the fourth resistor is electrically connected to the source of the second transistor and the non-inverting input end of the second amplifier respectively, and a second end of the fourth resistor is grounded.
[0031] In the embodiment of the present application, when the current corresponding to the LIN signal suddenly becomes high, the voltage value on the fourth resistor increases, causing the output voltage value of the second amplifier to increase, that is, the gate voltage of the first transistor increases; due to the increase in the gate voltage of the first transistor, the down-injection current of the first transistor is reduced, thereby reducing the gate voltage of the second transistor, and finally reducing the current corresponding to the LIN signal. Since the difference between the voltage value on the fourth resistor and the first electrical signal is used in the present application to reduce the current corresponding to the LIN signal, the LIN signal finally obtained is more accurate.
[0032] In a possible implementation manner, the second control circuit includes:
[0033] A third transistor, wherein a source of the third transistor is grounded, a gate of the third transistor is electrically connected to a first end of the fourth resistor, and a drain of the third transistor is electrically connected to a drain of the first transistor.
[0034] In the embodiment of the present application, when the current corresponding to the LIN signal suddenly becomes high, the voltage value on the fourth resistor increases, causing the gate voltage of the third transistor to increase, and the pull-down current of the third transistor to increase, thereby reducing the gate voltage of the second transistor, and finally reducing the current corresponding to the LIN signal. In the present application, when the current corresponding to the LIN signal suddenly becomes high, the third transistor can respond quickly, and then the current corresponding to the LIN signal can be reduced more quickly, reducing the impact caused by the excessive current corresponding to the LIN signal.
[0035] In a possible implementation, the control module further includes:
[0036] a fifth resistor, a first end of the fifth resistor being electrically connected to the LIN bus;
[0037] A first capacitor, wherein a first end of the first capacitor is electrically connected to a second end of the fifth resistor, and a second end of the first capacitor is electrically connected to a gate of the second transistor.
[0038] In an embodiment of the present application, when the corresponding LIN signal on the LIN bus receives noise interference, the noise interference signal can pass through the feedback circuit formed by the fifth resistor and the first capacitor, causing the gate voltage of the second transistor to increase or decrease, thereby increasing or decreasing the current corresponding to the LIN signal to offset the influence of the noise interference.
[0039] In a possible implementation, the control module further includes:
[0040] A first diode, wherein an anode of the first diode is electrically connected to the LIN bus, and a cathode of the first diode is electrically connected to a drain of the second transistor, wherein the anode of the first diode is an output terminal of the control module.
[0041] In the embodiment of the present application, the control module may further include a diode for isolating the internal electrical signal of the control module to prevent the influence on the LIN signal on the LIN bus.
[0042] In a possible implementation, when the current output by the ramp power supply is I C When the first electrical signal output by the corresponding signal output module is V 1 =I C ×R 1 ; After passing through the amplification module, the second electrical signal determined at the output end of the first amplifier is V 2 =(1+R 2 / R 3 )V 1 Since the control module can make the voltage at the first end of the fourth resistor the same as the second electrical signal, when the current corresponding to the LIN signal is I LIN When C ×R 1 ×(1+R 2 / R 3 )=I LIN ×R 4 . Due to R 1 -R 4 The resistance value is determined, and the current corresponding to the LIN signal can be determined according to the current output by the ramp power supply, and finally the current value corresponding to the LIN signal is controlled to be the preset current value. 1 -R 4 They represent the first resistor, the second resistor, the third resistor and the fourth resistor respectively.
[0043] In general, the resistance values of R1 and R4 are set to be the same or to match them as much as possible on the layout.C It can be reduced by (1+R 2 / R 3 ) times, achieving controllable configuration of LIN current.
[0044] In a second aspect, an embodiment of the present application provides a LIN interface chip, including:
[0045] A slope control circuit for a LIN bus according to any one of the first aspects.
[0046] In a third aspect, an embodiment of the present application provides a microprocessor chip, including:
[0047] Any one of the slope control circuits of the LIN bus in the first aspect. It can be understood that the LIN interface chip provided in the second aspect includes the slope control circuit for executing the LIN bus provided in the present application, and the microprocessor chip provided in the third aspect includes the LIN interface chip provided in the present application. Therefore, the beneficial effects that can be achieved can refer to the beneficial effects of the slope control circuit of the LIN bus in the first aspect, which will not be repeated here. BRIEF DESCRIPTION OF THE DRAWINGS
[0048] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.
[0049] Figure 1 A schematic diagram of an application scenario provided for an embodiment of the present application.
[0050] Figure 2 A schematic diagram of a trapezoidal wave provided in an embodiment of the present application.
[0051] Figure 3 A slope control circuit suitable for a LIN bus is provided in an embodiment of the present application.
[0052] Figure 4 A schematic diagram of the structure of a signal output module provided in an embodiment of the present application.
[0053] Figure 5 A schematic diagram of the structure of a control module provided in an embodiment of the present application.
[0054] Figure 6 A schematic diagram of the structure of another control module provided in an embodiment of the present application.
[0055] Figure 7 A schematic diagram of the structure of another control module provided in an embodiment of the present application.
[0056] Figure 8 Another slope control circuit suitable for a LIN bus is provided in an embodiment of the present application.
[0057] Fig. 9 A schematic diagram of the structure of an amplification module provided in an embodiment of the present application.
[0058] Fig.10 Another slope control circuit suitable for a LIN bus is provided in an embodiment of the present application. DETAILED DESCRIPTION
[0059] In order to better understand the technical solution of the present application, the embodiments of the present application are described in detail below with reference to the accompanying drawings.
[0060] It should be clear that the described embodiments are only 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 ordinary technicians in the field without creative work are within the scope of protection of the present application.
[0061] The terms used in the embodiments of the present application are only for the purpose of describing specific embodiments, and are not intended to limit the present application. The singular forms "a", "said" and "the" used in the embodiments of the present application and the appended claims are also intended to include plural forms, unless the context clearly indicates other meanings.
[0062] It should be understood that the term "and / or" used in this article is only a description of the association relationship of associated objects, indicating that there can be three relationships. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. In addition, the character " / " in this article generally indicates that the associated objects before and after are in an "or" relationship.
[0063] To facilitate understanding, a specific application scenario is first exemplified below.
[0064] See also Figure 1 , is a schematic diagram of an application scenario provided by an embodiment of the present application. Figure 1 As shown, the application scenario includes: a printer 100. The printer 100 includes: a LIN main control unit 101, a paper feed motor 102, an indicator light 103, a heating roller 104 and a LIN bus 105. Among them, the LIN main control unit 101, the paper feed motor 102, the indicator light 103 and the heating roller 104 are all connected to the LIN bus 105. It can be understood that the LIN main control unit 101, the paper feed motor 102, the indicator light 103 and the heating roller 104 can transmit information between each other through the LIN bus 105 based on the LIN communication protocol.
[0065] Specifically, when information is transmitted between devices based on the LIN communication protocol, the LIN signal transmitted on the LIN bus is usually a trapezoidal wave. It can be understood that when different information needs to be transmitted, different trapezoidal wave signals are output accordingly. For ease of understanding, see Figure 2 , is a schematic diagram of a trapezoidal wave provided in an embodiment of the present application. Figure 2 As shown, the figure shows a trapezoidal wave 201. At the same time, the figure also shows two dotted lines, which represent 60% and 40% of the rectangular wave voltage value from top to bottom respectively. Among them, the upper dotted line and the trapezoidal wave 201 constitute a recessive area 202, and the time period t1 corresponding to the recessive area 202 is used to represent the first level information, such as 1, etc.; the lower dotted line and the trapezoidal wave 201 constitute an explicit area 203, and the time period t2 corresponding to the linear area 203 is used to represent the second level information, such as 0, etc. Of course, the two dotted lines in the figure can also represent 80% and 20% of the rectangular wave voltage value from top to bottom, etc., and this application does not make specific restrictions on this.
[0066] in addition, Figure 1 The printer 100 shown in the figure is only an exemplary description, and the application scenarios of the LIN bus may also include vehicles, etc., and this application does not make specific restrictions on this. Figure 1 The LIN bus slaves shown in the figure: the paper feeding motor 102, the indicator light 103 and the heating roller 104 are only an exemplary description, and the present application does not impose any specific limitation on this.
[0067] Since the LIN bus transmits information between devices through the LIN signal (trapezoidal wave signal), an ideal LIN signal needs to be obtained before the LIN bus is used to transmit information between devices. In the related art, a LIN signal slope control circuit constructed by an ordinary current mirror is usually used to directly control the slope corresponding to the LIN signal on the LIN bus, thereby obtaining a LIN signal.
[0068] However, the LIN signal slope control circuit constructed by the common current mirror is greatly affected by PVT. Therefore, when the LIN signal slope control circuit constructed by the common current mirror is used to directly control the slope corresponding to the LIN signal on the LIN bus, due to the influence of PVT, the current corresponding to the LIN signal output by the relevant LIN signal slope control circuit may be unstable, and finally the determined LIN signal is not ideal.
[0069] In response to the above problems, in an embodiment of the present application, the signal output module outputs a first electrical signal corresponding to a preset slope; the control module is used to output a first control signal at the output end of the control module according to the first electrical signal. Due to the first control signal determined by the control module, in addition to adjusting the slope of the corresponding LIN signal on the LIN bus to a preset slope, the current value of the corresponding LIN signal on the LIN bus can also be adjusted to a preset current value. It can be understood that when the voltage value of the corresponding LIN signal on the LIN bus is too high or too low, the first control signal determined by the control module dynamically adjusts the voltage value of the LIN signal, so that the voltage value of the corresponding LIN signal on the LIN bus is the preset voltage, and then the current corresponding to the LIN signal will not be too large or too small, so a more ideal LIN signal can be obtained. Specifically, it is described in detail below in conjunction with the accompanying drawings and specific embodiments.
[0070] See also Figure 3 , is a slope control circuit applicable to a LIN bus provided in an embodiment of the present application. The slope control circuit can be applied to Figure 1 In the application scenario shown, Figure 3 As shown in the figure, a LIN bus 301 and a slope control circuit 302 are shown. The slope control circuit 302 includes: a signal output module 3021 and a control module 3022. Figure 3 As shown, the connection relationship between the modules is: the signal output module 3021 is electrically connected to the control module 3022; the control module 3022 is electrically connected to the LIN bus 301.
[0071] It should be pointed out that in order to more clearly show the connection relationship and related functions of the slope control circuit applicable to the LIN bus, Figure 3 LIN bus 301 is also shown in FIG. It can be understood that Figure 3 The LIN bus shown in the figure should not be used as a specific limitation of this application. Those skilled in the art can also apply the slope control circuit to other signal transmission devices according to actual needs, and this application does not make specific limitations on this.
[0072] For ease of understanding, the following will Figure 3 The signal output module 3021 and the control module 3022 shown in the figure are described one by one.
[0073] In the embodiments of the present application, Figure 3 The signal output module shown in is used to output a first electrical signal corresponding to a preset slope. It can be understood that the voltage value output by the signal output module corresponds to the preset slope.
[0074] In a possible implementation, the slope corresponding to the electrical signal output by the signal output module is a preset slope. Exemplarily, when it is necessary to control the slope corresponding to the rising edge or falling edge of the LIN signal to be a first slope, the preset slope is set to be the first slope. At this time, the slope corresponding to the electrical signal output by the signal output module is the first slope.
[0075] In a possible implementation, the present application embodiment further provides a structural diagram of a signal output module. Figure 4 , is a structural schematic diagram of a signal output module provided in an embodiment of the present application. As shown in the figure, a ramp current source I and a first resistor R1 are shown. Among them, the input end of the ramp current source is electrically connected to the voltage source; the output end of the ramp current source is electrically connected to the first end of the first resistor; the second end of the first resistor is grounded; the first end of the first resistor is electrically connected to the input end of the control module. Among them, the first end of the first resistor is the output end of the signal output module. It should be pointed out that in order to more clearly show the circuit structure of the signal output module, some related circuits are not shown in the figure.
[0076] Specifically, the ramp current source outputs a current corresponding to a preset slope, and after the current passes through the first resistor, the first electrical signal is outputted to the outside at the first end of the first resistor. Of course, those skilled in the art may also design other circuits to obtain the first electrical signal corresponding to the preset slope according to actual needs, and the present application does not impose any specific restrictions on the specific structure of the circuit.
[0077] Of course, those skilled in the art may also design other circuits to determine the first electrical signal according to actual needs, and this application does not impose any specific limitation on this.
[0078] The "slope current source" mentioned above is a current source that can output a slope with a preset slope. It is understandable that the slope current source can be implemented by an analog circuit or a digital circuit, and this application does not make any specific restrictions on this.
[0079] In a possible implementation, the current corresponding to the preset slope output by the ramp current source is a zero temperature coefficient current, that is, the current is not affected by temperature.
[0080] In the embodiments of the present application, Figure 3 The control module shown in the figure is used to output a first control signal at the output end of the control module according to the first electrical signal. The first control signal is used to adjust the slope of the corresponding LIN signal on the LIN bus to a preset slope and control the corresponding current value of the LIN signal to be a preset current value.
[0081] Specifically, the control module first receives the first electrical signal, and then controls the slope of the corresponding LIN signal on the LIN bus to be a preset slope according to the first electrical signal. At the same time, the control module controls the current value corresponding to the LIN signal to be a preset current value according to the first electrical signal. It can be understood that when the current value corresponding to the LIN signal is too large or too small, the first electrical signal quickly adjusts the current value corresponding to the LIN signal to the preset current value.
[0082] In a possible implementation, the control module includes a first control circuit and a second control circuit, and the second control circuit controls the current corresponding to the LIN signal faster than the first control circuit.
[0083] In an embodiment of the present application, the control module includes a first control circuit and a second control circuit. Since the second control circuit controls the current corresponding to the LIN signal faster than the first control circuit, and usually the first control circuit controls the current corresponding to the LIN signal more accurately, the control module can better meet the requirements of different reaction speeds and different adjustment accuracy in combination with specific application scenarios.
[0084] In a possible implementation, the present application embodiment also provides a structural diagram of a control module. Figure 5 , which is a structural schematic diagram of a control module provided in an embodiment of the present application. As shown in the figure, the figure shows a second amplifier I2, a first transistor M1, a second transistor M2 and a fourth resistor R4. Among them, the inverting input terminal of the second amplifier is electrically connected to the output terminal of the signal output module; the source of the first transistor is electrically connected to the voltage source, and the gate of the first transistor is electrically connected to the output terminal of the second amplifier; the gate of the second transistor is electrically connected to the drain of the first transistor, and the drain of the second transistor is electrically connected to the LIN bus; the first end of the fourth resistor is electrically connected to the source of the second transistor and the in-phase input terminal of the second amplifier, respectively, and the second end of the fourth resistor is grounded. The first end of the fourth resistor is electrically connected to the source of the second transistor and the in-phase input terminal of the second amplifier, respectively, and the second end of the fourth resistor is grounded. It should be pointed out that in order to more clearly show the circuit structure of the control module, some related circuits are not shown in the figure. It is understandable that, Figure 5 The second amplifier I2, the first transistor M1, the second transistor M2 and the fourth resistor R4 shown constitute the first control circuit mentioned above.
[0085] It can be understood that the inverting input terminal of the second amplifier is the input terminal of the control module, and the drain of the second transistor is the output terminal of the control module.
[0086] In the embodiments of the present application, Figure 5As shown, the second amplifier will limit the voltage of the corresponding inverting input terminal and the voltage of the non-inverting input terminal to the same voltage value, that is, control the voltage of the first end of the fourth resistor to be the first electrical signal. Specifically, when the voltage of the first end of the fourth resistor is different from the first electrical signal, the output end of the second amplifier outputs a voltage value corresponding to the difference voltage, which is the gate voltage of the first transistor. When the gate voltage of the first transistor changes, the gate voltage of the corresponding second transistor changes accordingly. When the gate voltage of the second transistor changes, the source-drain current of the corresponding second transistor changes, thereby causing the voltage of the first end of the fourth resistor to change accordingly so that the voltage of the first end of the fourth resistor is the first electrical signal. Correspondingly, at this time, the current value corresponding to the LIN signal on the LIN bus is controlled by the voltage of the fourth resistor and the first end of the fourth resistor.
[0087] It can be understood that the "difference voltage" mentioned above is the difference between the voltage received by the control module receiving end and the voltage at the in-phase input end of the second amplifier, that is, the difference between the voltage received by the control module receiving end and the voltage at the first end of the fourth resistor.
[0088] Of course, those skilled in the art may also design other circuits to control the LIN signal on the LIN bus according to actual needs, and this application does not impose any specific limitation on this.
[0089] In actual use, although Figure 5 The control module shown can adjust the slope of the corresponding LIN signal on the LIN bus to a preset slope, and control the corresponding current value of the LIN signal to be a preset current value. When the current value corresponding to the LIN signal is too large, the current value corresponding to the LIN signal will be adjusted to an appropriate value through the adjustment of the control module described above, that is, the current value corresponding to the LIN signal is controlled to be a preset current value. However, when the current corresponding to the LIN signal is too large, the reaction time for adjusting the current corresponding to the LIN signal to an appropriate current is relatively long. Therefore, a fast conduction loop can be designed to reduce the current corresponding to the LIN signal. Specifically, it is described in detail below in conjunction with the accompanying drawings and specific embodiments.
[0090] It can be understood that the current corresponding to the LIN signal is in a corresponding relationship with the slope of the LIN signal, that is, the slope of the LIN signal is inversely proportional to the current corresponding to the LIN signal.
[0091] See also Figure 6 , is a schematic diagram of the structure of another control module provided in an embodiment of the present application. Figure 6 As shown, in Figure 5On the basis of, the control module further includes a third transistor M3. As shown in the figure, the source of the third transistor is grounded, the gate of the third transistor is electrically connected to the first end of the fourth resistor, and the drain of the third transistor is electrically connected to the drain of the first transistor. It can be understood that Figure 6 The third transistor, the second transistor and the fourth resistor shown in the figure constitute the second control circuit mentioned above.
[0092] Specifically, when the current corresponding to the corresponding LIN signal on the LIN bus is too large, the voltage value of the first end of the fourth resistor is high, the corresponding gate voltage of the third transistor increases, and the third transistor is turned on, thereby reducing the gate voltage of the second transistor, thereby controlling the source-drain current of the second transistor, and finally reducing the current value of the LIN signal.
[0093] It can be understood that the reaction speed of the loop formed by the third transistor to rapidly reduce the current value corresponding to the LIN signal is relatively faster, and a more ideal LIN signal can be obtained more quickly.
[0094] Of course, in a possible implementation, the control module may include the design of the first control circuit and the second control circuit at the same time, so as to better meet the requirements of different reaction speeds and different adjustment precisions.
[0095] Of course, those skilled in the art may also design other circuits to control the LIN signal on the LIN bus according to actual needs, and this application does not impose any specific limitation on this.
[0096] In practical applications, there may be noise interference on the LIN bus, which may cause the current value of the corresponding LIN signal to be pulled up. To address this problem, a feedback circuit can be set in the control module. When there is noise interference, the pull-down current can be increased or decreased to offset the effect of the noise interference on the LIN signal. Specifically, a detailed description is given below in conjunction with the accompanying drawings.
[0097] See also Figure 7 , is a schematic diagram of the structure of another control module provided in an embodiment of the present application. Figure 7 As shown, in Figure 6 On the basis of, the control module also includes a fifth resistor R5 and a first capacitor C1. As shown in the figure, the first end of the fifth resistor is electrically connected to the LIN bus; the first end of the first capacitor is electrically connected to the second end of the fifth resistor, and the second end of the first capacitor is electrically connected to the gate of the second transistor. It should be pointed out that in order to more clearly show the circuit structure of the control module, some related circuits are not shown in the figure.
[0098] Specifically, when the corresponding LIN signal on the LIN bus receives noise interference, the noise interference signal will pass through the feedback circuit formed by the fifth resistor and the first capacitor, for example, increasing the gate voltage of the second transistor, thereby increasing the current value corresponding to the LIN signal to offset the influence of the noise interference.
[0099] In a possible implementation, the control module may further include a diode for preventing the control module from affecting the LIN bus. Specifically, the anode of the first diode is electrically connected to the LIN bus, and the cathode of the first diode is electrically connected to the drain of the second transistor. At this time, the anode of the first diode is the output terminal of the control module.
[0100] Of course, those skilled in the art may also design other circuits to control the LIN signal on the LIN bus according to actual needs, and this application does not impose any specific limitation on this.
[0101] In the embodiment of the present application, due to the first control signal determined by the control module, in addition to adjusting the slope of the corresponding LIN signal on the LIN bus to a preset slope, the current value of the corresponding LIN signal on the LIN bus can also be adjusted to a preset current value. It can be understood that when the voltage value of the corresponding LIN signal on the LIN bus is too high or too low, the first control signal determined by the control module dynamically adjusts the voltage value of the LIN signal, so that the voltage value of the corresponding LIN signal on the LIN bus is the preset voltage, thereby preventing the current on the LIN bus from being too large or too small, so that a relatively ideal LIN signal can be obtained.
[0102] In practical applications, the signal output module is directly electrically connected to the output end of the control module. Due to the specific structure of the circuit, the circuit may be unstable and generate a corresponding large current. To avoid the generation of a large current inside the slope control circuit, a voltage amplification module may be connected between the signal output module and the control module. Specifically, a detailed description is given below in conjunction with the accompanying drawings and specific embodiments.
[0103] See also Figure 8 , which is another slope control circuit applicable to the LIN bus provided in the embodiment of the present application. The slope control circuit can be applied to Figure 1 In the application scenario shown, Figure 3 On the basis of FIG. 3 , the figure also shows an amplification module 3023. The input end of the amplification module is electrically connected to the output end of the signal output module, and the output end of the amplification module is electrically connected to the input end of the control module.
[0104] Specifically, in an embodiment of the present application, the amplification module is used to amplify the first electrical signal and output a corresponding second electrical signal at the output end of the amplification module; at this time, the control module is used to output a first control signal at the output end of the control module according to the second electrical signal.
[0105] It can be understood that by connecting an amplification module between the signal output module and the control module, the input impedance of the amplification module is high and the output impedance is low, so that the first electrical signal can be amplified into a second electrical signal, and the waveform of the second electrical signal can be ensured to be consistent with that of the first electrical signal, thereby making the voltage value of the corresponding LIN signal on the LIN bus a preset voltage, and finally obtaining a more ideal LIN signal.
[0106] In a possible implementation, the present application embodiment also provides a schematic diagram of the structure of an amplification module. Fig. 9 , which is a structural schematic diagram of an amplification module provided in an embodiment of the present application. As shown in the figure, the figure shows a first amplifier I1, a second resistor R2 and a third resistor R3. Among them, the in-phase input terminal of the first amplifier is electrically connected to the output terminal of the signal output module; the first end of the second resistor is electrically connected to the output terminal of the first amplifier, and the second end of the second resistor is electrically connected to the inverting input terminal of the first amplifier; the first end of the third resistor is electrically connected to the inverting input terminal of the first amplifier, and the second end of the third resistor is grounded. It should be pointed out that in order to more clearly show the circuit structure of the amplification module, some related circuits are not shown in the figure.
[0107] It can be understood that the in-phase input terminal of the first amplifier is the input terminal of the amplification module; and the output terminal of the first amplifier is the output terminal of the amplification module.
[0108] Of course, those skilled in the art may also design other circuits to determine the second electrical signal according to actual needs, and this application does not impose any specific limitation on this.
[0109] In the embodiment of the present application, an amplifying module is formed by the first amplifier, the second resistor and the third resistor, so that the output impedance of the amplifying module is low, the output current of the amplifying module can be effectively controlled, and a more ideal LIN signal can be obtained.
[0110] In a possible implementation, the first transistor, the second transistor, and the third transistor described above operate in the saturation region of the transistor. Of course, those skilled in the art may also set some or all of the first transistor, the second transistor, and the third transistor to operate in other regions according to actual needs, and this application does not impose any specific restrictions on this.
[0111] For easier understanding, see Fig.10, is another slope control circuit applicable to the LIN bus provided by the embodiment of the present application. As shown in the figure, Fig.10 is Figure 3 Based on the above, a specific slope control circuit of the LIN bus is determined. As shown in the figure, the LIN bus 301, the signal output module 3021, the control module 3022 and the amplification module 3023 are shown. The specific functions of the LIN bus 301, the signal output module 3021, the control module 3022 and the amplification module 3023 can refer to the description of the embodiment described above. For the sake of simplicity, this application will not be repeated here.
[0112] Specifically, in the embodiment of the present application, the slope control circuit of the LIN bus specifically includes: a LIN bus 301, a signal output module 3021, a control module 3022 and an amplification module 3023. The signal output module 3021 includes: a slope current source I and a first resistor R1; the control module 3022 includes: a second amplifier I2, a first transistor M1, a second transistor M2, a fourth resistor R4, a third transistor M3, a fifth resistor R5, a first capacitor C1 and a first diode D1. Specifically, the connection relationship of the slope control circuit of the LIN bus is as follows: the input end of the slope current source I is electrically connected to the voltage source; the output end of the slope current source I is electrically connected to the first end of the first resistor; the second end of the first resistor is grounded; the first end of the first resistor is electrically connected to the in-phase input end of the first amplifier; the output end of the first amplifier is electrically connected to the first end of the second resistor; the second end of the second resistor is electrically connected to the inverting input end of the first amplifier; the first end of the third resistor is electrically connected to the inverting input end of the first amplifier; the second end of the third resistor is grounded; the output end of the first amplifier is electrically connected to the inverting input end of the second amplifier; the source of the first transistor is electrically connected to the voltage source; the gate of the first transistor is electrically connected to the second The output end of the amplifier is electrically connected; the gate of the second transistor is electrically connected to the drain of the first transistor; the drain of the second transistor is electrically connected to the negative electrode of the first diode; the first end of the fourth resistor is electrically connected to the source of the second transistor and the in-phase input end of the second amplifier respectively; the second end of the fourth resistor is grounded; the source of the third transistor is grounded; the gate of the third transistor is electrically connected to the first end of the fourth resistor; the drain of the third transistor is electrically connected to the drain of the first transistor; the first end of the fifth resistor is electrically connected to the LIN bus; the first end of the first capacitor is electrically connected to the second end of the fifth resistor, and the second end of the first capacitor is electrically connected to the gate of the second transistor; the anode of the first diode is electrically connected to the first end of the fifth resistor.
[0113] It should be pointed out that Fig.10 The structural diagram of the slope control circuit applicable to the LIN bus shown is only an exemplary description. Those skilled in the art may also design other circuits according to actual needs, and this application does not impose any specific limitation on this.
[0114] Specifically, when the current output by the ramp power supply is I C When the first electrical signal output by the corresponding signal output module is V 1 =I C ×R 1 ; After passing through the amplification module, the second electrical signal determined at the output end of the first amplifier is V 2 =(1+R 2 / R 3 )V 1 Since the control module can make the voltage at the first end of the fourth resistor the same as the second electrical signal, when the current corresponding to the LIN signal is I LIN When C ×R 1 ×(1+R 2 / R 3 )=I LIN ×R 4 Since the resistance values of R1-R4 are determined, the current corresponding to the LIN signal can be determined according to the current output by the ramp power supply, and the current value corresponding to the LIN signal is finally controlled to be a preset current value.
[0115] In general, R 1 and R 4 The resistance values of the resistors are set to be the same or the two are matched as much as possible on the layout. C It can be reduced by (1+R 2 / R 3 ) times, achieving controllable configuration of LIN current.
[0116] Corresponding to the above embodiment, the embodiment of the present application also provides a LIN interface chip.
[0117] In an embodiment of the present application, the LIN interface chip includes the slope control circuit of the LIN bus described above. The specific functions and specific implementation methods of the slope control circuit of the LIN bus refer to the specific embodiments described above. For the sake of brevity, this application will not elaborate on this.
[0118] Corresponding to the above-mentioned embodiment, the embodiment of the present application further provides a microprocessor chip. The microprocessor chip may be, for example, an MCU, a DSP, an MPU, a micro CPU, or a micro central control chip or a system-on-chip chip that can process digital signals, analog signals, or perform signal control functions, instruction processing, and calculation functions.
[0119] In the embodiment of the present application, the microprocessor chip includes the slope control circuit of the LIN bus described above. The specific functions and specific implementation methods of the slope control circuit of the LIN bus refer to the specific embodiments described above. For the sake of brevity, this application does not elaborate here.
[0120] In the embodiments of the present application, "at least one" refers to one or more, and "plurality" refers to two or more. "And / or" describes the association relationship of associated objects, indicating that three relationships may exist. For example, A and / or B can represent the existence of A alone, the existence of A and B at the same time, and the existence of B alone. Among them, A and B can be singular or plural. The character " / " generally indicates that the previous and subsequent associated objects are in an "or" relationship. "At least one of the following" and similar expressions refer to any combination of these items, including any combination of single or plural items. For example, at least one of a, b and c can be represented by: a, b, c, ab, ac, bc, or abc, where a, b, c can be single or multiple.
[0121] Those of ordinary skill in the art will appreciate that the various units and algorithm steps described in the embodiments disclosed herein can be implemented in a combination of electronic hardware, computer software, and electronic hardware. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professional and technical personnel can use different methods to implement the described functions for each specific application, but such implementation should not be considered to be beyond the scope of this application.
[0122] Those skilled in the art can clearly understand that, for the convenience and brevity of description, the specific working processes of the systems, devices and units described above can refer to the corresponding processes in the aforementioned method embodiments and will not be repeated here.
[0123] In several embodiments provided in the present application, any function can be stored in a computer-readable storage medium if it is implemented in the form of a software functional unit and sold or used as an independent product. Based on this understanding, the technical solution of the present application can be essentially or partly embodied in the form of a software product that contributes to the prior art. The computer software product is stored in a storage medium, including several instructions for a computer device (which can be a personal computer, a server, or a network device, etc.) to perform all or part of the steps of the method described in each embodiment of the present application. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (ROM), random access memory (RAM), disk or optical disk, etc., and other media that can store program codes.
[0124] In this specification, the same or similar parts between the various embodiments can be referred to each other. In particular, for the device embodiment and the terminal embodiment, since they are basically similar to the method embodiment, the description is relatively simple, and the relevant parts can be referred to the description in the method embodiment.
Claims
1. A slope control circuit, characterized in that: include: A signal output module, the signal output module is used to output a first electrical signal corresponding to a preset slope; A control module, wherein the input end of the control module is electrically connected to the output end of the signal output module, and the output end of the control module is electrically connected to the LIN bus. The control module is used to output a first control signal at the output end of the control module according to the first electrical signal, and the first control signal is used to adjust the slope of the corresponding LIN signal on the LIN bus to a preset slope, and control the corresponding current value of the LIN signal to be a preset current value.
2. The slope control circuit according to claim 1, characterized in that: The control module comprises: a first control circuit and a second control circuit, wherein the second control circuit controls the current corresponding to the LIN signal faster than the first control circuit.
3. The slope control circuit according to claim 2, characterized in that: The first control circuit comprises: A second amplifier, an inverting input terminal of the second amplifier is electrically connected to the output terminal of the signal output module, wherein the inverting input terminal of the second amplifier is the input terminal of the control module; a first transistor, wherein a source of the first transistor is electrically connected to a voltage source, and a gate of the first transistor is electrically connected to an output terminal of the second amplifier; a second transistor, wherein a gate of the second transistor is electrically connected to a drain of the first transistor, and a drain of the second transistor is electrically connected to an output end of the LIN bus, wherein the drain of the second transistor is an output end of the control module; A fourth resistor, wherein a first end of the fourth resistor is electrically connected to the source of the second transistor and the non-inverting input end of the second amplifier respectively, and a second end of the fourth resistor is grounded.
4. The slope control circuit according to claim 3, characterized in that: The second control circuit comprises: A third transistor, wherein a source of the third transistor is grounded, a gate of the third transistor is electrically connected to a first end of the fourth resistor, and a drain of the third transistor is electrically connected to a drain of the first transistor.
5. The slope control circuit according to claim 3 or 4, characterized in that: The control module also includes: a fifth resistor, a first end of the fifth resistor being electrically connected to the LIN bus; A first capacitor, wherein a first end of the first capacitor is electrically connected to a second end of the fifth resistor, and a second end of the first capacitor is electrically connected to a gate of the second transistor.
6. The slope control circuit according to claim 3 or 4, characterized in that: The control module also includes: A first diode, wherein an anode of the first diode is electrically connected to the LIN bus, and a cathode of the first diode is electrically connected to a drain of the second transistor, wherein the anode of the first diode is an output terminal of the control module.
7. The slope control circuit according to claim 1, characterized in that: It also includes an amplification module, the amplification module including: A first amplifier, wherein a non-inverting input terminal of the first amplifier is electrically connected to an output terminal of the signal output module; a second resistor, wherein a first end of the second resistor is electrically connected to the output end of the first amplifier, and a second end of the second resistor is electrically connected to the inverting input end of the first amplifier; A third resistor, wherein a first end of the third resistor is electrically connected to the inverting input end of the first amplifier, and a second end of the third resistor is grounded.
8. The slope control circuit according to claim 1, characterized in that: The signal output module comprises: A ramp current source, the ramp current source being used to output a corresponding ramp current according to the preset slope; A first resistor, wherein a first end of the first resistor is electrically connected to the output end of the ramp current source, and a second end of the first resistor is grounded, wherein the first end of the first resistor is the output end of the signal output module.
9. A LIN interface chip, characterized in that: include: The slope control circuit of any one of claims 1 to 8.
10. A microprocessor chip, characterized in that: include: The slope control circuit of any one of claims 1 to 8.