Control circuit for lin signal slope
By designing a LIN signal slope control circuit and utilizing a combination of slope control circuit, drive control circuit, and level pull-up/pull-down circuit, the instability problem of the LIN bus signal under voltage and temperature changes was solved, and stable signal control was achieved.
Patent Information
- Application Number
- CN202411814174.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-11
- Publication Date
- 2025-12-16
- Estimated Expiration
- 2044-12-11
AI Technical Summary
Existing LIN transceivers cannot guarantee that the slope signal of the LIN bus remains constant when the voltage and temperature change, resulting in signal instability.
A control circuit for the slope of a LIN signal was designed, including a slope control circuit, a drive control circuit, a level pull-up circuit, and a level pull-down circuit. By accurately detecting signal changes and performing negative feedback control, the rising and falling edges of the LIN signal are kept stable.
This ensures that the rising and falling edges of the LIN bus signal remain constant despite changes in voltage and temperature, guaranteeing signal stability and accuracy.
Smart Images
Figure CN119781331B_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The present application relates to the field of integrated circuit design, and in particular to a LIN signal slope control circuit. BACKGROUND
[0002] LIN (Local Interconnect Network) bus is a low-cost serial communication protocol based on UART / SCI (Universal Asynchronous Receiver / Transmitter / Serial Interface), and is widely used in the fields of vehicle body control such as door, window, light and central locking in modern automotive electronic architecture.
[0003] At present, most of the LIN transceivers on the market are designed based on open-loop principle or use fixed slope, and when the voltage and temperature change, the slope signal of the LIN bus cannot be guaranteed to remain unchanged. SUMMARY
[0004] The technical problem to be solved by the present application is to overcome the defect that the conventional slope control circuit cannot obtain ideal LIN signal in the prior art, and to provide a LIN signal slope control circuit.
[0005] The present application solves the above technical problems by the following technical solutions:
[0006] In a first aspect, a LIN signal slope control circuit is provided, which comprises a first input end, a slope control circuit, a drive control circuit, a second input end, a third input end, a fourth input end, a level pull-up circuit, a level pull-down circuit, and an output end.
[0007] The second input end, the third input end, and the fourth input end are electrically connected to one end of the level pull-down circuit, the first input end is electrically connected to one end of the slope control circuit, the other end of the slope control circuit is electrically connected to one end of the drive control circuit, the other end of the drive control circuit is electrically connected to one end of the level pull-up circuit, the other end of the level pull-up circuit is electrically connected to the output end, and the other end of the level pull-down circuit is electrically connected to the output end.
[0008] The second input end is used for inputting a first voltage signal, the third input end is used for inputting a second voltage signal, the fourth input end is used for inputting a third voltage signal, and the first input end is used for inputting the second voltage signal.
[0009] The slope control circuit is used for controlling the waveform change of a VNX voltage signal generated according to the second voltage signal, and inputting a BIAS voltage signal converted according to the VNX voltage signal into the drive control circuit.
[0010] The driving control circuit is configured to control a waveform change of a VND voltage signal generated according to the BIAS voltage signal, and input the VND voltage signal to the level pull-up circuit.
[0011] The level pull-up circuit is configured to perform pull-up control on an output voltage signal of the output terminal according to the VND voltage signal.
[0012] The level pull-down circuit is configured to perform pull-down control on the output voltage signal of the output terminal according to the first voltage signal, the second voltage signal and the third voltage signal.
[0013] Preferably, the driving control circuit comprises a first control terminal, a current mirror circuit, a low-level control circuit and a negative feedback structure circuit.
[0014] One end of the current mirror circuit is electrically connected to the low-level control circuit, and the other end of the current mirror circuit is electrically connected to the negative feedback structure circuit. The current mirror circuit, the low-level control circuit and the negative feedback structure circuit are electrically connected to the first control terminal.
[0015] The current mirror circuit, the low-level control circuit and the negative feedback structure circuit jointly control the slope of rising and falling edges of the VND voltage signal input to the level pull-up circuit.
[0016] Preferably, the low-level control circuit comprises a first PMOS transistor, a first NMOS transistor, a second NMOS transistor, a third NMOS transistor and a fourth NMOS transistor.
[0017] The drain of the first PMOS transistor is electrically connected to the drain of the first NMOS transistor, the source of the first NMOS transistor is electrically connected to the drain of the second NMOS transistor, the source of the second NMOS transistor is electrically connected to the drain of the third NMOS transistor, and the source of the third NMOS transistor is electrically connected to the gate of the fourth NMOS transistor.
[0018] Preferably, the current mirror circuit comprises a second PMOS transistor and a third PMOS transistor.
[0019] Preferably, the negative feedback structure circuit comprises a fifth NMOS transistor and a sixth NMOS transistor, and the gate of the fifth NMOS transistor is electrically connected to the drain of the sixth NMOS transistor.
[0020] Preferably, the slope control circuit comprises a second control terminal, a control circuit, a detection circuit, a pull-up current circuit and a pull-down current circuit.
[0021] One end of the control circuit is electrically connected with one end of the detection circuit, the pull-up current circuit and the pull-down current circuit are electrically connected with the other end of the detection circuit, and the control circuit, the detection circuit, the pull-up current circuit and the pull-down current circuit are electrically connected with the second control end;
[0022] The control circuit, the detection circuit, the pull-up current circuit and the pull-down current circuit jointly control the slope of the rising edge and the falling edge of the VNX voltage signal input to the second control end;
[0023] The second control end is used for amplifying and converting the VNX voltage signal into the BIAS voltage signal, and inputting the BIAS voltage signal into the drive control circuit.
[0024] Preferably, the control circuit comprises a high-level control circuit and a first amplifier;
[0025] The negative electrode of the first amplifier is electrically connected with the high-level control circuit, and the positive electrode of the first amplifier is electrically connected with the detection circuit;
[0026] The high-level control circuit is used for controlling the rising edge corresponding to the VNX voltage signal.
[0027] Preferably, the detection circuit comprises a fourth PMOS tube, a fifth PMOS tube, a sixth PMOS tube, a seventh NMOS tube, an eighth NMOS tube, a ninth NMOS tube, a tenth NMOS tube and an eleventh NMOS tube;
[0028] The fifth PMOS tube and the sixth PMOS tube are electrically connected with the source electrode of the fourth PMOS tube; the drain electrode of the seventh NMOS tube and the gate electrode of the eighth NMOS tube are electrically connected with the drain electrode of the fourth PMOS tube;
[0029] The drain electrode of the ninth NMOS tube is electrically connected with the drain electrode of the sixth PMOS tube, the source electrode of the ninth NMOS tube is electrically connected with the drain electrode of the tenth NMOS tube, and the gate electrode of the tenth NMOS tube is electrically connected with the eleventh NMOS tube.
[0030] Preferably, the pull-up current circuit comprises an eighth PMOS tube, a ninth PMOS tube and a twelfth NMOS tube;
[0031] The source electrode of the ninth PMOS tube and the drain electrode of the twelfth NMOS tube are electrically connected with the drain electrode of the eighth PMOS tube.
[0032] Preferably, the pull-down current circuit comprises a tenth PMOS tube, a thirteenth NMOS tube and a fourteenth NMOS tube;
[0033] The drain of the thirteenth NMOS transistor and the gate of the fourteenth NMOS transistor are both electrically connected to the drain of the tenth PMOS transistor.
[0034] The positive and progressive effects of this invention are as follows: It provides a control circuit for the slope of a LIN signal, which accurately detects changes in the LIN signal through a slope control circuit, a drive control circuit, a level pull-up circuit, and a level pull-down circuit, so as to achieve precise negative feedback control and ensure that the rising and falling edges of the LIN bus signal tend to remain unchanged when the voltage and temperature of the LIN signal change. Attached Figure Description
[0035] Figure 1 This is a first schematic diagram illustrating the working principle of the LIN signal slope control circuit in Embodiment 1 of the present invention.
[0036] Figure 2 This is a second schematic diagram illustrating the working principle of the LIN signal slope control circuit in Embodiment 1 of the present invention.
[0037] Figure 3 This is a circuit diagram of the first implementation of the LIN signal slope control circuit in Embodiment 1 of the present invention.
[0038] Figure 4 This is a third schematic diagram illustrating the working principle of the LIN signal slope control circuit in Embodiment 1 of the present invention.
[0039] Figure 5 This is a circuit diagram of a second implementation of the LIN signal slope control circuit in Embodiment 1 of the present invention.
[0040] Figure 6 This is a circuit diagram of a third implementation of the LIN signal slope control circuit in Embodiment 1 of the present invention. Detailed Implementation
[0041] The present invention will be further illustrated by way of embodiments below, but the present invention is not limited to the scope of the embodiments described herein.
[0042] Example 1
[0043] This embodiment provides a control circuit for the slope of a LIN signal, such as... Figure 1 As shown, the control circuit consists of: first input terminal 1, slope control circuit 2, drive control circuit 3, second input terminal 4, third input terminal 5, fourth input terminal 6, level pull-up circuit 7, level pull-down circuit 8, and output terminal 9.
[0044] The second input end 4, the third input end 5, the fourth input end 6 are electrically connected with one end of the level pull-down circuit 8, the first input end 1 is electrically connected with one end of the slope control circuit 2, the other end of the slope control circuit 2 is electrically connected with one end of the drive control circuit 3, the other end of the drive control circuit 3 is electrically connected with one end of the level pull-up circuit 7, the other end of the level pull-up circuit 7 is electrically connected with the output end 9, the other end of the level pull-down circuit 8 is electrically connected with the output end 9;
[0045] The second input end 4 is used for inputting the first voltage signal, the third input end 5 is used for inputting the second voltage signal, the fourth input end 6 is used for inputting the third voltage signal, and the first input end 1 is used for inputting the second voltage signal;
[0046] The slope control circuit 2 is used for controlling the waveform change of the VNX voltage signal generated according to the second voltage signal, and inputting the BIAS voltage signal converted according to the VNX voltage signal into the drive control circuit 3;
[0047] The drive control circuit 3 is used for controlling the waveform change of the VND voltage signal generated according to the BIAS voltage signal, and inputting the VND voltage signal into the level pull-up circuit;
[0048] The level pull-up circuit 7 is used for performing pull-up control on the output voltage signal of the output end 9 according to the VND voltage signal;
[0049] The level pull-down circuit 8 is used for performing pull-down control on the output voltage signal of the output end 9 according to the first voltage signal, the second voltage signal and the third voltage signal.
[0050] In the embodiment, after the second voltage signal is stably input into the slope control circuit 2 through the first input end 1, the slope control circuit 2 controls the rising edge and the falling edge of the LIN driving gate voltage waveform by controlling the high level and the rising edge and the falling edge of the VNX voltage signal. The drive control circuit 3 controls the VND waveform generated by the BIAS voltage signal, and the level pull-up circuit 7 controls the periodic change of the output voltage signal of the output end 9 by controlling the waveform change of the VND voltage signal, thereby performing slope control on the LIN signal. The first voltage signal, the second voltage signal and the third voltage signal are input into the second input end 4, the third input end 5 and the fourth input end 6 to perform pull-down control on the output voltage signal of the output end 9. This mode ensures stable output of the LIN signal under various conditions, accurately controls the LIN signal, and realizes accurate control of the rising edge and the falling edge of the LIN signal.
[0051] Figure 2 The second schematic diagram of the working principle of the slope control circuit for the LIN signal, the drive control circuit 3 includes: a current mirror circuit 31, a low level control circuit 32, a negative feedback structure circuit 33 and a first control end 34;
[0052] One end of the current mirror circuit 31 is electrically connected with the low level control circuit 32, the other end of the current mirror circuit 31 is electrically connected with the negative feedback structure circuit 33, the current mirror circuit 31, the low level control circuit 32 and the negative feedback structure circuit 33 are electrically connected with the first control end 34;
[0053] The current mirror circuit 31, the low level control circuit 32 and the negative feedback structure circuit 33 jointly control the slope of the rising edge and the falling edge of the VND voltage signal input to the level pull-up circuit 7.
[0054] In this embodiment, the VND voltage signal is jointly controlled by the branch of the current mirror circuit 31, the branch of the low level control circuit 32 and the branch of the negative feedback structure circuit 33, so as to control the waveform change of the VND.
[0055] Figure 3 The circuit diagram of the first implementation mode of the control circuit of the LIN signal slope, the low level control circuit 32 comprises a first PMOS tube, a first NMOS tube, a second NMOS tube, a third NMOS tube and a fourth NMOS tube.
[0056] The drain of the first PMOS tube is electrically connected with the drain of the first NMOS tube, the source of the first NMOS tube is electrically connected with the drain of the second NMOS tube, the source of the second NMOS tube is electrically connected with the drain of the third NMOS tube, and the source of the third NMOS tube is electrically connected with the gate of the fourth NMOS tube.
[0057] The current mirror circuit 31 comprises a second PMOS tube and a third PMOS tube.
[0058] The negative feedback structure circuit 33 comprises a fifth NMOS tube and a sixth NMOS tube, and the gate of the fifth NMOS tube is electrically connected with the drain of the sixth NMOS tube.
[0059] In this embodiment, the MP2 tube of the BIAS voltage controls the periodic change of the VND voltage signal, the low level control circuit 32 composed of MP1, MN1, MN2, MN3 and MN4 controls the low level signal of the first control end 34, and the negative feedback structure circuit 33 composed of MN5 and MN6 realizes the negative feedback control of the first control end 34. The level pull-down circuit 8 is composed of one MPOS tube and three MNOS tubes, the level pull-up circuit 7 is composed of R3, R2, R4 and the MNOS tube electrically connected with R3, and the two circuits jointly control the periodic change of the voltage signal of the GN output end, so as to realize the accurate slope control of the LIN signal.
[0060] Figure 4The third schematic view of the working principle of the control circuit of the LIN signal slope, the slope control circuit 2 comprises: a second control end 21, a control circuit 22, a detection circuit 23, a pull-up current circuit 24 and a pull-down current circuit 25;
[0061] One end of the control circuit 22 is electrically connected with one end of the detection circuit 23, the pull-up current circuit 24 and the pull-down current circuit 25 are electrically connected with the other end of the detection circuit 23, and the control circuit, the detection circuit, the pull-up current circuit 24 and the pull-down current circuit 25 are electrically connected with the second control end 21;
[0062] The control circuit 22, the detection circuit 23, the pull-up current circuit 24 and the pull-down current circuit 25 jointly control the slope of the rising edge and the falling edge corresponding to the VNX voltage signal input to the second control end 21;
[0063] The second control end 21 is used for amplifying and converting the VNX voltage signal into a BIAS voltage signal, and inputting the BIAS voltage signal into the drive control circuit 3.
[0064] In the embodiment, the branch where the control circuit 22 is located, the branch where the detection circuit 23 is located, the branch where the pull-up current circuit 24 is located and the branch where the pull-down current circuit 25 is located jointly control the VNX voltage signal, so as to control the waveform change of the VNX, and make the waveform of the VNX present periodic change.
[0065] Figure 5 The second implementation manner of the circuit diagram of the control circuit of the LIN signal slope, the control circuit 22 comprises a high-level control circuit and a first amplifier;
[0066] The negative electrode of the first amplifier is electrically connected with the high-level control circuit, and the positive electrode of the first amplifier is electrically connected with the detection circuit;
[0067] The high-level control circuit is used for controlling the rising edge corresponding to the VNX voltage signal.
[0068] The detection circuit 23 comprises a fourth PMOS tube, a fifth PMOS tube, a sixth PMOS tube, a seventh NMOS tube, an eighth NMOS tube, a ninth NMOS tube, a tenth NMOS tube and an eleventh NMOS tube;
[0069] The fifth PMOS tube and the sixth PMOS tube are electrically connected with the source electrode of the fourth PMOS tube; the drain electrode of the seventh NMOS tube and the gate electrode of the eighth NMOS tube are electrically connected with the drain electrode of the fourth PMOS tube;
[0070] The drain electrode of the ninth NMOS tube is electrically connected with the drain electrode of the sixth PMOS tube, the source electrode of the ninth NMOS tube is electrically connected with the drain electrode of the tenth NMOS tube, and the gate electrode of the tenth NMOS tube is electrically connected with the eleventh NMOS tube.
[0071] The pull-up current circuit 24 comprises an eighth PMOS, a ninth PMOS and a twelfth NMOS;
[0072] The source of the ninth PMOS and the drain of the twelfth NMOS are electrically connected to the drain of the eighth PMOS.
[0073] The pull-down current circuit 25 comprises a tenth PMOS, a thirteenth NMOS and a fourteenth NMOS;
[0074] The drain of the thirteenth NMOS and the gate of the fourteenth NMOS are electrically connected to the drain of the tenth PMOS.
[0075] In the embodiment, the detection circuit 23 is composed of MP4, MP5, MP6, MN7, MN8, MN9, MN10 and MN11, the pull-up current circuit 24 is composed of MP8, MP9 and MN12, the pull-down current circuit 25 is composed of MP10, MN13 and NM14, and the control circuit 23 is composed of the amplifier follow and OPA1, which together control the waveform change of the VNX voltage signal, so that the waveform of VNX presents periodic change, thereby controlling the waveform change of the BIAS voltage signal converted from the VNX voltage signal.
[0076] Figure 6 The third implementation of the circuit diagram of the control circuit for the LIN signal slope, the control circuit 22 comprises five MPOS and two MNOS, which controls the high level of the VNX voltage signal and realizes the accurate control of the waveform of the VNX input into the second control end.
[0077] The embodiment provides a control circuit for the LIN signal slope, which accurately detects the signal change of the LIN through the slope control circuit, the driving control circuit, the level pull-up circuit and the level pull-down circuit, so as to realize the accurate negative feedback control and ensure that the rising and falling edges of the LIN bus signal tend to be unchanged when the voltage of the LIN signal changes with temperature.
[0078] Although the specific embodiments of the present application are described above, those skilled in the art should understand that this is only an example, and the protection scope of the present application is defined by the appended claims. Those skilled in the art can make various changes or modifications to these embodiments without departing from the principles and essence of the present application, and these changes and modifications all fall within the protection scope of the present application.
Claims
1. A control circuit for the slope of a LIN signal, characterized in that, The control circuit includes: a first input terminal, a slope control circuit, a drive control circuit, a second input terminal, a third input terminal, a fourth input terminal, a pull-up circuit, a pull-down circuit, and an output terminal. The second input terminal, the third input terminal, and the fourth input terminal are all electrically connected to one end of the pull-down circuit. The first input terminal is electrically connected to one end of the slope control circuit. The other end of the slope control circuit is electrically connected to one end of the drive control circuit. The other end of the drive control circuit is electrically connected to one end of the pull-up circuit. The other end of the pull-up circuit is electrically connected to the output terminal. The other end of the pull-down circuit is electrically connected to the output terminal. The second input terminal is used to input a first voltage signal, the third input terminal is used to input a second voltage signal, the fourth input terminal is used to input a third voltage signal, and the first input terminal is used to input the second voltage signal; The slope control circuit is used to control the waveform change of the VNX voltage signal generated according to the second voltage signal, and to input the BIAS voltage signal generated according to the VNX voltage signal into the drive control circuit. The drive control circuit is used to control the slope of the rising and falling edges of the VND voltage signal generated according to the BIAS voltage signal, and input the VND voltage signal into the level pull-up circuit. The pull-up circuit is used to pull up the output voltage signal at the output terminal according to the VND voltage signal; The pull-down circuit is used to control the output voltage signal at the output terminal by pulling it down according to the first voltage signal, the second voltage signal and the third voltage signal. The slope control circuit includes: a second control terminal, a control circuit, a detection circuit, a pull-up current circuit, and a pull-down current circuit; One end of the control circuit is electrically connected to one end of the detection circuit, the pull-up current circuit and the pull-down current circuit are both electrically connected to the other end of the detection circuit, and the control circuit, the detection circuit, the pull-up current circuit and the pull-down current circuit are all electrically connected to the second control terminal; The control circuit, the detection circuit, the pull-up current circuit, and the pull-down current circuit jointly control the slope of the rising and falling edges of the VNX voltage signal input to the second control terminal. The second control terminal is used to amplify the VNX voltage signal and convert it into the BIAS voltage signal, and input the BIAS voltage signal into the drive control circuit.
2. The LIN signal slope control circuit as described in claim 1, characterized in that, The drive control circuit includes: a first control terminal, a current mirror circuit, a low-level control circuit, and a negative feedback structure circuit; One end of the current mirror circuit is electrically connected to the low-level control circuit, and the other end of the current mirror circuit is electrically connected to the negative feedback structure circuit. The current mirror circuit, the low-level control circuit, and the negative feedback structure circuit are all electrically connected to the first control terminal. The current mirror circuit, the low-level control circuit, and the negative feedback structure circuit jointly control the slope of the rising and falling edges of the VND voltage signal input to the pull-up circuit.
3. The LIN signal slope control circuit as described in claim 2, characterized in that, The low-level control circuit includes: a first PMOS transistor, a first NMOS transistor, a second NMOS transistor, a third NMOS transistor, and a fourth NMOS transistor; The drain of the first PMOS transistor is electrically connected to the drain of the first NMOS transistor, the source of the first NMOS transistor is electrically connected to the drain of the second NMOS transistor, the source of the second NMOS transistor is electrically connected to the drain of the third NMOS transistor, and the source of the third NMOS transistor is electrically connected to the gate of the fourth NMOS transistor.
4. The LIN signal slope control circuit as described in claim 2, characterized in that, The current mirror circuit includes a second PMOS transistor and a third PMOS transistor.
5. The LIN signal slope control circuit as described in claim 2, characterized in that, The negative feedback structure circuit includes a fifth NMOS transistor and a sixth NMOS transistor; The gate of the fifth NMOS transistor is electrically connected to the drain of the sixth NMOS transistor.
6. The LIN signal slope control circuit as described in claim 1, characterized in that, The control circuit includes a high-level control circuit and a first amplifier; The negative terminal of the first amplifier is electrically connected to the high-level control circuit, and the positive terminal of the first amplifier is electrically connected to the detection circuit. The high-level control circuit is used to control the rising edge of the VNX voltage signal.
7. The LIN signal slope control circuit as described in claim 1, characterized in that, The detection circuit includes a fourth PMOS transistor, a fifth PMOS transistor, a sixth PMOS transistor, a seventh NMOS transistor, an eighth NMOS transistor, a ninth NMOS transistor, a tenth NMOS transistor, and an eleventh NMOS transistor; The fifth PMOS transistor and the sixth PMOS transistor are both electrically connected to the source of the fourth PMOS transistor; the drain of the seventh NMOS transistor and the gate of the eighth NMOS transistor are both electrically connected to the drain of the fourth PMOS transistor. The drain of the ninth NMOS transistor is electrically connected to the drain of the sixth PMOS transistor, the source of the ninth NMOS transistor is electrically connected to the drain of the tenth NMOS transistor, and the gate of the tenth NMOS transistor is electrically connected to the eleventh NMOS transistor.
8. The LIN signal slope control circuit as described in claim 1, characterized in that, The pull-up current circuit includes an eighth PMOS transistor, a ninth PMOS transistor, and a twelfth NMOS transistor; The source of the ninth PMOS transistor and the drain of the twelfth NMOS transistor are both electrically connected to the drain of the eighth PMOS transistor.
9. The LIN signal slope control circuit as described in claim 1, characterized in that, The pull-down current circuit includes a tenth PMOS transistor, a thirteenth NMOS transistor, and a fourteenth NMOS transistor; The drain of the thirteenth NMOS transistor and the gate of the fourteenth NMOS transistor are both electrically connected to the drain of the tenth PMOS transistor.
Citation Information
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