Vehicle source driving circuit and operation method thereof

Abstract

The present invention discloses a vehicle source driving circuit. The vehicle source driving circuit includes a plurality of output channels and an output voltage detection circuit. The plurality of output channels are coupled to a vehicle display panel to output a plurality of output voltages to the vehicle display panel. The output voltage detection circuit includes a judgment module and a notification module. The judgment module is coupled to the plurality of output channels to respectively detect the plurality of output voltages output by the plurality of output channels during a specific period and to judge whether the plurality of output voltages are abnormal according to a preset output voltage range. The notification module is coupled to the judgment module. If the judgment result of the judgment module is yes, the notification module immediately outputs a notification signal to activate a safe state to comply with specific specifications.

Description

Technical Field

[0001] The present invention relates to a source driving circuit, and in particular to a vehicle source driving circuit and an operation method thereof. Background Art

[0002] In recent years, as the importance of automotive safety has been increasingly recognized and the ISO26262 standard has become more popular, all automotive systems on the market are required to have functional safety as specified by ISO26262.

[0003] Please refer to Figure 1 , Figure 1 The schematic diagram of the automotive source driver integrated circuit SIC applied to the automotive display panel PL. Generally speaking, in order to comply with the functional safety specified by ISO26262 and achieve the hardware quantitative indicators (SPFM / LFM / PMHF) above the ASIL B level, each functional module included in the automotive source driver integrated circuit SIC applied to the automotive display panel PL must have a redundant design or safety mechanism.

[0004] Among the entire automotive display integrated circuit, the automotive source driver integrated circuit SIC usually occupies the largest area. In addition, once the automotive display integrated circuit has an abnormality (such as particle, EOS, ESD, etc.), it usually also causes the output of the automotive source driver integrated circuit SIC to be abnormal.

[0005] However, conventional automotive source driver integrated circuits (SICs) do not have any output abnormality detection and notification mechanism, which will directly violate the safety goal and make it impossible to achieve the functional safety specified by ISO26262. Therefore, further improvement is urgently needed. Summary of the invention

[0006] In view of this, the present invention provides a vehicle source driving circuit and an operating method thereof to effectively solve the above problems encountered in the prior art.

[0007] According to a specific embodiment of the present invention, a vehicle source driver circuit is provided. In this embodiment, the vehicle source driver circuit includes a plurality of output channels and an output voltage detection circuit. The plurality of output channels are coupled to a vehicle display panel to output a plurality of output voltages to the vehicle display panel. The output voltage detection circuit includes a judgment module and a notification module. The judgment module is coupled to the plurality of output channels to respectively detect the plurality of output voltages output by the plurality of output channels during a specific period and to judge whether the plurality of output voltages are abnormal according to a preset output voltage range. The notification module is coupled to the judgment module. If the judgment result of the judgment module is yes, the notification module immediately outputs a notification signal to activate a safe state to comply with specific specifications.

[0008] In one embodiment, the specific period refers to the time from when the vehicle source driving circuit is powered on to before the normal display period of the vehicle display panel, and a black image or a white image is inserted first in the specific period.

[0009] In one embodiment, the specific period refers to a vertical blanking period (V-Blanking) within a normal display period of the vehicle display panel.

[0010] In one embodiment, the output voltage detection circuit further includes a plurality of switching modules respectively coupled between the plurality of output channels and the determination module, and configured to sequentially switch some of the output channels to be coupled to the determination module according to a line shift signal.

[0011] In one embodiment, the judgment module includes a first comparator for comparing the plurality of output voltages with a preset output voltage upper limit of a preset output voltage range. If at least one of the plurality of output voltages is higher than the preset output voltage upper limit, the judgment module determines that the plurality of output voltages are abnormal.

[0012] In one embodiment, the judgment module includes a second comparator for comparing the multiple output voltages with a preset output voltage lower limit of the preset output voltage range. If at least one output voltage among the multiple output voltages is lower than the preset output voltage lower limit, the judgment module determines that the multiple output voltages are abnormal.

[0013] In one embodiment, the notification module controls a specific pin through a timing controller to output a notification signal with a low level to the front-end system, thereby notifying the front-end system to make the vehicle source driving circuit enter a safe state.

[0014] In one embodiment, the notification module controls a specific pin through a timing controller to output a notification signal with a low level to the front-end system, thereby notifying the front-end system to make the vehicle source driving circuit enter a safe state.

[0015] In one embodiment, the specific standard is the ISO26262 standard.

[0016] Another specific embodiment of the present invention is a method for operating a vehicle source driver circuit. In this embodiment, the method for operating a vehicle source driver circuit is used to operate a vehicle source driver circuit. The vehicle source driver circuit includes a plurality of output channels coupled to a vehicle display panel. The method for operating a vehicle source driver circuit includes the following steps: (a) outputting a plurality of output voltages to the vehicle display panel through the plurality of output channels; (b) detecting the plurality of output voltages output by the plurality of output channels during a specific period; (c) determining whether the plurality of output voltages are abnormal according to a preset output voltage range; and (d) if the determination result of step (c) is yes, immediately outputting a notification signal to activate a safe state.

[0017] Compared to the prior art, the automotive source driver circuit and its operating method according to the present invention propose a detection and notification mechanism for output abnormalities of the automotive source driver circuit, so that when the automotive source driver circuit detects output abnormalities, it can immediately notify the front-end system to enter a safe state to meet the safety goals, thereby achieving the functional safety of the ISO26262 specification and the hardware quantitative indicators of the ASIL level specification.

[0018] The advantages and spirit of the present invention can be further understood through the following detailed description of the invention and the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 The schematic diagram is a schematic diagram of an automotive source driver integrated circuit applied to an automotive display panel.

[0020] Figure 2A The diagram is a schematic diagram showing that a plurality of output channels of a vehicle source driving circuit according to a specific embodiment of the present invention are divided into a first part to a fourth part.

[0021] Figure 2B The fourth part (output channels SOUT1801 to SOUT2400) is used as an example to illustrate a schematic diagram of a vehicle source driving circuit.

[0022] Figure 3 A timing diagram showing a specific period during which a voltage range check is to be performed.

[0023] Figure 4 The figure is a schematic diagram of the self-detection function when the automotive source driver circuit is turned on.

[0024] Figure 5 FIG. 4 is a flow chart of an operating method of a vehicle source driving circuit according to another specific embodiment of the present invention.

[0025] Figure 6 FIG. 4 is a flow chart of an operating method of a vehicle source driving circuit according to another specific embodiment of the present invention.

[0026] Description of main component symbols:

[0027] PL Automotive Display Panel

[0028] DA display area

[0029] SIC Automotive Source Driver Integrated Circuit

[0030] GIC Automotive Gate Driver Integrated Circuit

[0031] GP Gate pulse signal

[0032] SDAT data signal

[0033] ERROPB Notification Signal

[0034] SOUT1~SOUT600 output channel

[0035] SOUT601~SOUT1200 output channel

[0036] SOUT1201~SOUT1800 output channel

[0037] SOUT1801~SOUT2400 output channel

[0038] SA Part 1

[0039] SB Part 2

[0040] SC Part 3

[0041] SD Part 4

[0042] 20 Source driver module

[0043] 21 Output voltage detection circuit

[0044] 22 Switching Module

[0045] 24-Polarity Multiplexer Module

[0046] 26 Judgment module

[0047] 28 Notification Module

[0048] POP First Operational Amplifier

[0049] NOP Second operational amplifier

[0050] OM1~OM300 Output Multiplexer

[0051] LSS Linear Displacement Signal

[0052] SW1~SW600 Switching unit

[0053] POL polarity signal

[0054] CP1 First comparator

[0055] CP2 Second comparator

[0056] CP3 Third comparator

[0057] CP4 Fourth comparator

[0058] + Positive input

[0059] - Negative input

[0060] VHTH preset output voltage upper limit

[0061] VHTL preset output voltage lower limit

[0062] VLTH preset output voltage upper limit

[0063] VLTL Preset output voltage lower limit

[0064] TCON Timing Controller

[0065] CON Notification Signal

[0066] VDD Operating Voltage

[0067] GRB / STBYB Display switch control signal

[0068] F1 First frame

[0069] F2 Second frame

[0070] F3 3rd frame

[0071] F4 Fourth frame

[0072] F5 Fifth frame

[0073] FN Frame N

[0074] FN+1 Frame N+1

[0075] FN+2 Frame N+2

[0076] FN+3 Frame N+3

[0077] FN+4 Frame N+4

[0078] PM Polarity Multiplexer Module

[0079] VH High Voltage Level

[0080] VL Low Voltage Level

[0081] Steps S10 to S16

[0082] Steps S20 to S26

[0083] HI High level

[0084] LO Low Level DETAILED DESCRIPTION

[0085] According to a specific embodiment of the present invention, a vehicle source driving circuit is provided. In this embodiment, the vehicle source driving circuit can be applied to various vehicle display devices to drive a vehicle display panel to display, but is not limited thereto.

[0086] First, please refer to Figure 2A , Figure 2A This is a schematic diagram showing that a plurality of output channels of the vehicle source driving circuit in this embodiment are divided into a first part to a fourth part.

[0087] like Figure 2A As shown, the vehicle source driving circuit SIC includes a plurality of output channels SOUT1-SOUT2400 for respectively outputting a plurality of output voltages to the vehicle display panel. In practical applications, the plurality of output channels SOUT1-SOUT2400 can be divided into a plurality of parts.

[0088] For example, if the output channels SOUT1~SOUT2400 are equally divided into the first part SA to the fourth part SD, the first part SA includes output channels SOUT1~SOUT600, the second part SB includes output channels SOUT601~SOUT1200, the third part SC includes output channels SOUT1201~SOUT1800 and the fourth part SD includes output channels SOUT1801~SOUT2400.

[0089] Next, please refer to Figure 2B , Figure 2B The fourth part SD (ie, output channels SOUT1801 - SOUT2400 ) is taken as an example to illustrate a schematic diagram of a vehicle source driving circuit.

[0090] like Figure 2B As shown, the vehicle source driving circuit includes a source driving module 20 and an output voltage detection circuit 21. The source driving module 20 includes a fourth part SD (i.e., a plurality of output channels SOUT1801-SOUT2400). The source driving module 20 and the output voltage detection circuit 21 are coupled to each other. In fact, the plurality of output channels SOUT1801-SOUT2400 can be coupled to a vehicle display panel to output a plurality of output voltages to the vehicle display panel.

[0091] In this embodiment, the source driver module 20 includes a plurality of pairs of first operational amplifiers POP and second operational amplifiers NOP, a plurality of output multiplexers OM1 ˜ OM300 , and a plurality of output channels SOUT1801 ˜ SOUT2400 .

[0092] Taking the first pair of the first operational amplifier POP and the second operational amplifier NOP as an example, an input terminal and an output terminal of the first operational amplifier POP are both coupled to an input terminal of the output multiplexer OM1, and an input terminal and an output terminal of the second operational amplifier NOP are both coupled to another input terminal of the output multiplexer OM1. The two output terminals of the output multiplexer OM1 are respectively coupled to the corresponding two output channels SOUT1801 and SOUT1802.

[0093] Similarly, if the second pair of the first operational amplifier POP and the second operational amplifier NOP is taken as an example, an input terminal and an output terminal of the first operational amplifier POP are both coupled to an input terminal of the output multiplexer OM2, and an input terminal and an output terminal of the second operational amplifier NOP are both coupled to another input terminal of the output multiplexer OM2. The two output terminals of the output multiplexer OM2 are respectively coupled to the corresponding two output channels SOUT1803 and SOUT1804.

[0094] By analogy, if the 300th pair of the first operational amplifier POP and the second operational amplifier NOP is taken as an example, an input terminal and an output terminal of the first operational amplifier POP are both coupled to an input terminal of the output multiplexer OM300, and an input terminal and an output terminal of the second operational amplifier NOP are both coupled to another input terminal of the output multiplexer OM300. The two output terminals of the output multiplexer OM300 are respectively coupled to the corresponding two output channels SOUT2399 and SOUT2400.

[0095] In this embodiment, the output voltage detection circuit 21 includes a switching module 22, a polarity multiplexing module 24, a determination module 26 and a notification module 28. The switching module 22 is coupled to the source driving module 20. The polarity multiplexing module 24 is coupled to the switching module 22. The determination module 26 is coupled to the polarity multiplexing module 24. The notification module 28 is coupled to the determination module 26.

[0096] The switching module 22 includes a plurality of switching units SW1-SW600, which are respectively coupled between the plurality of output channels SOUT1801-SOUT2400 and the polarity multiplexing module 24, and are used to sequentially switch some of the output channels SOUT1801-SOUT2400 to be coupled to two input ends of the polarity multiplexing module 24 according to a line shift signal LSS.

[0097] For example, the switching module 22 can switch the odd-numbered switching units SW1, SW3, ..., SW599 among the multiple switching units SW1~SW600 to couple to an input end of the polarity multiplexing module 24 according to the line shift signal LSS, and switch the even-numbered switching units SW2, SW4, ..., SW600 among the multiple switching units SW1~SW600 to couple to another input end of the polarity multiplexing module 24 according to the line shift signal LSS, but is not limited to this.

[0098] The polarity multiplexing module 24 is coupled between the switching module 22 and the judging module 26 to switch the coupling relationship between the multiple switching units SW1-SW600 and the judging module 26 according to the polarity signal POL, so that the multiple output voltages output by the multiple output channels SOUT1801-SOUT2400 can be selectively transmitted to the judging module 26.

[0099] The determination module 26 is coupled between the polarity multiplexing module 24 and the notification module 28. The determination module 26 is used to perform a voltage range check during a specific period, for example, respectively detecting the multiple output voltages output by the multiple output channels SOUT1801-SOUT2400, and determining whether the multiple output voltages are abnormal according to a preset output voltage range and then outputting the determination result to the notification module 28. In actual applications, the preset output voltage range is between a preset output voltage upper limit and a preset output voltage lower limit.

[0100] Please refer to Figure 3 , Figure 3 is a timing diagram for a specific period during which a voltage range check is to be performed. Figure 3 As shown, when the vehicle source driving circuit is powered on, the first frame F1 and the second frame F2 before the normal display period of the vehicle display panel (starting from the fifth frame F5 when the backlight starts to start) can be inserted with a black screen, and the third frame F3 and the fourth frame F4 can be inserted with a white screen. Then, the first frame F1, the second frame F2, the third frame F3 and the fourth frame F4 can all be "specific periods" for voltage range check, but not limited to this. In addition, the vertical blanking period (V-Blanking) within the normal display period of the vehicle display panel (starting from the fifth frame F5 when the backlight starts to start) can also be a "specific period" for voltage range check, but not limited to this.

[0101] In this embodiment, the determination module 26 may include a plurality of comparators, such as Figure 2B The first comparator CP1 to the fourth comparator CP4 in the embodiment of the present invention are provided, but the present invention is not limited thereto. Figure 2BAs shown, if the preset output voltage range is between the preset output voltage upper limit VHTH and the preset output voltage lower limit VHTL, the positive input terminal + of the first comparator CP1 is coupled to the preset output voltage upper limit VHTH, the negative input terminal - of the first comparator CP1 and the positive input terminal + of the second comparator CP2 are both coupled to an output terminal of the polarity multiplexing module 24, and the negative input terminal - of the second comparator CP2 is coupled to the preset output voltage lower limit VHTL. The output terminals of the first comparator CP1 and the second comparator CP2 are both coupled to the notification module 28.

[0102] For the first comparator CP1, if the output voltage received by its negative input terminal - from the output terminal of the polarity multiplexer module 24 is higher than the preset output voltage upper limit VHTH received by its positive input terminal +, it means that the output voltage is outside the preset output voltage range, and the first comparator CP1 outputs the judgment result that the output voltage is abnormal to the notification module 28; if the output voltage received by its negative input terminal - from the output terminal of the polarity multiplexer module 24 is not higher than the preset output voltage upper limit VHTH, it means that the output voltage is still within the preset output voltage range, and the first comparator CP1 outputs the judgment result that the output voltage is not abnormal to the notification module 28.

[0103] For the second comparator CP2, if the output voltage received by its positive input terminal + from the output terminal of the polarity multiplexer module 24 is lower than the preset output voltage lower limit VHTL received by its negative input terminal -, it means that the output voltage is outside the preset output voltage range, and the second comparator CP2 outputs the judgment result that the output voltage is abnormal to the notification module 28; if the output voltage received by its positive input terminal + from the output terminal of the polarity multiplexer module 24 is not lower than the preset output voltage lower limit VHTL, it means that the output voltage is still within the preset output voltage range, and the second comparator CP2 outputs the judgment result that the output voltage is not abnormal to the notification module 28.

[0104] Similarly, if the preset output voltage range is between the preset output voltage upper limit VLTH and the preset output voltage lower limit VLTL, the positive input terminal + of the third comparator CP3 is coupled to the preset output voltage upper limit VLTH, the negative input terminal - of the third comparator CP3 and the positive input terminal + of the fourth comparator CP4 are both coupled to the other output terminal of the polarity multiplexing module 24, and the negative input terminal - of the fourth comparator CP4 is coupled to the preset output voltage lower limit VLTL. The output terminals of the third comparator CP3 and the fourth comparator CP4 are both coupled to the notification module 28.

[0105] For the third comparator CP3, if the output voltage received by its negative input terminal - from the other output terminal of the polarity multiplexer module 24 is higher than the preset output voltage upper limit VLTH received by its positive input terminal +, it means that the output voltage is outside the preset output voltage range, and the third comparator CP3 outputs the judgment result that the output voltage is abnormal to the notification module 28; if the output voltage received by its negative input terminal - from the output terminal of the polarity multiplexer module 24 is not higher than the preset output voltage upper limit VLTH, it means that the output voltage is still within the preset output voltage range, and the third comparator CP3 outputs the judgment result that the output voltage is not abnormal to the notification module 28.

[0106] For the fourth comparator CP4, if the output voltage received by its positive input terminal + from the other output terminal of the polarity multiplexer module 24 is lower than the preset output voltage lower limit VLTL received by its negative input terminal -, it means that the output voltage is outside the preset output voltage range, and the fourth comparator CP4 outputs the judgment result that the output voltage is abnormal to the notification module 28; if the output voltage received by its positive input terminal + from the output terminal of the polarity multiplexer module 24 is not lower than the preset output voltage lower limit VHTL, it means that the output voltage is still within the preset output voltage range, and the fourth comparator CP4 outputs the judgment result that the output voltage is not abnormal to the notification module 28.

[0107] When the notification module 28 receives multiple judgment results from the first comparator CP1 to the fourth comparator CP4 respectively, if at least one of the judgment results is that the output voltage is abnormal, it means that at least one of the multiple output voltages is abnormal, then the notification module 28 will immediately output the notification signal CON to activate the safety state to comply with specific specifications (such as ISO26262 specifications, but not limited to this).

[0108] In practical applications, the notification module 28 can control a specific pin through its timing controller TCON to output a notification signal CON with a low level to the front-end system, thereby notifying the front-end system to make the vehicle source driving circuit enter a safe state, but the present invention is not limited thereto.

[0109] Please refer to Figure 4 , Figure 4 Schematic diagram of the self-test function that can be performed when the automotive source drive circuit is powered on. Figure 4 As shown, in Figure 2BThe first comparator CP1 to the fourth comparator CP4 in the judgment module 26 for detecting the source output voltage can perform a self-detection function when the vehicle source driving circuit is powered on. The comparison results of the first comparator CP1 to the fourth comparator CP4 can be obtained by inputting a high voltage level VH and a low voltage level VL (or vice versa) to the positive input terminal + and the negative input terminal - of the first comparator CP1 to the fourth comparator CP4, and the timing controller TCON determines whether the comparison results of the first comparator CP1 to the fourth comparator CP4 meet expectations. If the timing controller TCON determines that at least one of the comparison results does not meet expectations, the timing controller TCON will output a notification signal CON with a low level to the front-end system, thereby notifying the front-end system to make the vehicle source driving circuit enter a safe state, but not limited to this.

[0110] Another specific embodiment of the present invention is a method for operating a vehicle source driving circuit. In this embodiment, the method for operating a vehicle source driving circuit is used to operate a vehicle source driving circuit. The vehicle source driving circuit may include a plurality of output channels coupled to a vehicle display panel, but is not limited thereto.

[0111] Please refer to Figure 5 , Figure 5 This is a flow chart of the operation method of the vehicle source driving circuit in this embodiment. Figure 5 As shown, the operating method of the vehicle source driving circuit may include the following steps:

[0112] Step S10: outputting a plurality of output voltages to the vehicle display panel through a plurality of output channels;

[0113] Step S12: respectively detecting the plurality of output voltages outputted by the plurality of output channels during a specific period;

[0114] Step S14: determining whether the multiple output voltages are abnormal according to a preset output voltage range;

[0115] If the determination result of step S14 is yes, indicating that an abnormal output voltage occurs, step S16 is executed: immediately outputting a notification signal to activate a safe state.

[0116] On the contrary, if the determination result of step S14 is negative, it means that there is no abnormal output voltage, and the process returns to step S12 to continue detecting the output voltage.

[0117] It should be noted that the "specific period" described in step S12 may be a plurality of frames after the vehicle source driving circuit is powered on and before the normal display period of the vehicle display panel, which may be used to insert a black screen or a white screen, and the voltage range check is performed during these frames, but the present invention is not limited thereto. In addition, the "specific period" may also be a vertical blanking period (V-Blanking) within the normal display period of the vehicle display panel, and the voltage range check is performed during these vertical blanking periods, but the present invention is not limited thereto.

[0118] In practical applications, step S12 may sequentially switch some of the output channels of the plurality of output channels according to the line shift signal to detect the output voltage thereof, but the present invention is not limited thereto. The "specific standard" described in step S16 may be the ISO26262 standard, but the present invention is not limited thereto.

[0119] In one embodiment, the preset output voltage range may include a preset output voltage upper limit and a preset output voltage lower limit. Step S14 may compare the multiple output voltages with the preset output voltage upper limit respectively. If at least one of the multiple output voltages is higher than the preset output voltage upper limit, it may be determined that an abnormal output voltage has occurred. Similarly, step S14 may compare the multiple output voltages with the preset output voltage lower limit respectively. If at least one of the multiple output voltages is lower than the preset output voltage lower limit, it may be determined that an abnormal output voltage has occurred.

[0120] On the contrary, if the multiple output voltages are all within the preset output voltage range, that is, the multiple output voltages are not higher than the preset output voltage upper limit and are not lower than the preset output voltage lower limit, it can be determined that no output voltage abnormality occurs.

[0121] In one embodiment, step S16 can immediately control a specific pin through a timing controller to output a notification signal with a low level to the front-end system, thereby notifying the front-end system to make the vehicle source driving circuit enter a safe state, but the present invention is not limited thereto.

[0122] In actual applications, step S14 can also perform a self-detection function when the vehicle source drive circuit is powered on. It can generate a comparison result by inputting a high voltage level and a low voltage level to the two input terminals of each comparator respectively, and the timing controller determines whether the comparison result of each comparator meets expectations, but is not limited to this.

[0123] If at least one of the comparison results is negative, indicating that at least one comparator is detected to be abnormal, the timing controller will immediately control a specific pin to output a notification signal with a low level to the front-end system, thereby notifying the front-end system to put the automotive source driver circuit into a safe state to comply with the ISO26262 specification.

[0124] Please refer to Figure 6 , Figure 6 FIG. 1 is a flow chart of an operation method of a vehicle source driving circuit in another specific embodiment of the present invention. Figure 6 As shown, the operating method of the vehicle source driving circuit may include the following steps:

[0125] Step S20: power on (operating voltage VDD rises);

[0126] Step S21: Start the IC power-on sequence;

[0127] Step S22: input a black pattern (or other patterns) and check the source output voltage range;

[0128] Step S23: voltage range check;

[0129] If the check result of step S23 is Pass, it means that the output voltage is not abnormal, and a notification signal with a high level (ERROPB=HI) is output;

[0130] If the check result of step S23 is Failure (Fail), it means that the output voltage is abnormal, and a notification signal with a low level (ERROPB=LO) is output;

[0131] Next, after entering the normal display period, step S24 is performed: inputting a normal pattern and checking the source output voltage range during the vertical blanking period (V-Blanking);

[0132] Step S25: voltage range check;

[0133] If the check result of step S25 is passed, it means that the output voltage is not abnormal, and a notification signal with a high level (ERROPB=HI) is output;

[0134] If the checking result of step S25 is failure, which means that the output voltage is abnormal, a notification signal with a low level (ERROPB=LO) is output; and

[0135] Step S26: shut down (operating voltage VDD drops).

[0136] Compared to the prior art, the automotive source driver circuit and its operating method of the present invention propose a detection and notification mechanism for output abnormalities of the automotive source driver circuit, so that when the automotive source driver circuit detects output abnormalities, it can immediately notify the front-end system to enter a safe state to meet safety goals, thereby achieving the functional safety of the ISO26262 specification and the hardware quantitative indicators of the ASIL level specification.

Claims

1. A vehicle source driving circuit coupled to a vehicle display panel, characterized in that: include: A plurality of output channels are coupled to the vehicle display panel and are used to output a plurality of output voltages to the vehicle display panel; as well as An output voltage detection circuit comprises: a determination module coupled to the plurality of output channels, for respectively detecting the plurality of output voltages output by the plurality of output channels during a specific period and determining whether the plurality of output voltages are abnormal according to a preset output voltage range; and a notification module coupled to the determination module, and if the determination result of the determination module is yes, the notification module immediately outputs a notification signal to activate a safety state to meet a specific specification; Among them, the judgment module includes multiple comparators, which can perform a self-detection function when the vehicle source drive circuit is turned on. It generates multiple comparison results of the multiple comparators to a timing controller by inputting high voltage levels and low voltage levels to the multiple comparators, and the timing controller determines whether the multiple comparison results meet expectations. If the timing controller determines that at least one comparison result among the multiple comparison results does not meet expectations, the timing controller controls a specific pin to output the notification signal with a low level to a front-end system, thereby notifying the front-end system to allow the vehicle source drive circuit to enter the safe state.

2. The vehicle source driving circuit according to claim 1, characterized in that: The specific period refers to the time from when the vehicle source driving circuit is turned on to before a normal display period of the vehicle display panel, and a black picture or a white picture is inserted first in the specific period.

3. The vehicle source driving circuit according to claim 1, characterized in that: The specific period refers to a vertical blank period within a normal display period of the vehicle display panel.

4. The vehicle source driving circuit according to claim 1, characterized in that: The output voltage detection circuit further includes a switching module, which includes a plurality of switching modules respectively coupled between the plurality of output channels and the determination module, and is used to sequentially switch part of the output channels to be coupled to the determination module according to a line displacement signal.

5. The vehicle source driving circuit according to claim 1, characterized in that: The judgment module includes a first comparator for comparing the multiple output voltages with a preset output voltage upper limit of the preset output voltage range respectively. If at least one output voltage among the multiple output voltages is higher than the preset output voltage upper limit, the judgment module determines that the multiple output voltages are abnormal.

6. The vehicle source driving circuit according to claim 1, characterized in that: The judgment module includes a second comparator for comparing the multiple output voltages with a preset output voltage lower limit of the preset output voltage range respectively. If at least one output voltage among the multiple output voltages is lower than the preset output voltage lower limit, the judgment module determines that the multiple output voltages are abnormal.

7. The vehicle source driving circuit according to claim 1, characterized in that: This particular specification is the ISO 26262 specification.

8. A method for operating a vehicle source driving circuit, for operating a vehicle source driving circuit, wherein the vehicle source driving circuit comprises a plurality of output channels coupled to a vehicle display panel, wherein: The operating method of the vehicle source driving circuit includes the following steps: (a) outputting a plurality of output voltages to the vehicle display panel through the plurality of output channels; (b) respectively detecting the plurality of output voltages outputted by the plurality of output channels during a specific period; (c) determining whether the plurality of output voltages are abnormal according to a preset output voltage range; as well as (d) if the determination result of step (c) is yes, immediately outputting a notification signal to activate a safety state to comply with a specific specification; Among them, the automotive source drive circuit includes multiple comparators, which can perform a self-detection function when the automotive source drive circuit is turned on. It generates multiple comparison results of the multiple comparators by inputting high voltage levels and low voltage levels to the multiple comparators, and determines whether the multiple comparison results meet expectations. If at least one comparison result among the multiple comparison results does not meet expectations, a specific pin is controlled to output the notification signal with a low level to a front-end system, thereby notifying the front-end system to make the automotive source drive circuit enter the safe state.

9. The method for operating a vehicle source driving circuit according to claim 8, wherein: The specific period refers to inserting a black picture or a white picture before a normal display period of the vehicle display panel after the vehicle source driving circuit is turned on.

10. The method for operating a vehicle source driving circuit according to claim 8, wherein: The specific period refers to a vertical blank period within a normal display period of the vehicle display panel.

11. The method for operating a vehicle source driving circuit according to claim 8, wherein: Step (b) is to sequentially switch some of the output channels among the plurality of output channels according to a line shift signal during the specific period to detect the output voltage thereof.

12. The method for operating a vehicle source driving circuit according to claim 8, wherein: Step (c) includes: comparing the multiple output voltages with a preset output voltage upper limit of the preset output voltage range respectively, and determining that the multiple output voltages are abnormal if at least one output voltage among the multiple output voltages is higher than the preset output voltage upper limit.

13. The vehicle source driving circuit operation method according to claim 8, characterized in that: Step (c) includes: comparing the multiple output voltages with a preset output voltage lower limit of the preset output voltage range respectively, and determining that the multiple output voltages are abnormal if at least one output voltage among the multiple output voltages is lower than the preset output voltage lower limit.

14. The vehicle source driving circuit operation method according to claim 8, characterized in that: This particular specification is the ISO26262 specification.

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