Multi-channel acquisition circuit, multi-channel acquisition method, chip and vehicle

Abstract

The present application relates to a multi-channel acquisition circuit, a multi-channel acquisition method, a chip and a vehicle. The multi-channel acquisition circuit includes a first multi-way selection module, a voltage polarity adjustment module and a voltage acquisition module. The first multi-way selection module is used to obtain the analog voltages to be tested of different switches to be tested in turn according to the acquisition timing. The voltage polarity adjustment module adjusts the voltage polarity of the analog voltage to be tested in turn according to the acquisition timing. The voltage acquisition module is used to convert the analog voltage to be tested after the voltage polarity adjustment into a corresponding digital voltage. Not only can the single-polarity voltage acquisition module collect negative pressure, but also the multiple channels of the first multi-way selection module are turned on in turn. Therefore, only one voltage acquisition module is needed to perform time-sharing processing on the analog voltage to be tested transmitted through multiple channels, which reduces the complexity and cost of the multi-channel acquisition circuit.

Description

Technical Field

[0001] The present application relates to the field of electronic circuit technology, and in particular to a multi-channel acquisition circuit, a multi-channel acquisition method, a chip and a vehicle. Background Art

[0002] In traditional technology, a unipolar analog-to-digital converter (ADC) can only detect unipolar voltage signals, and a unipolar voltage signal refers to a voltage signal whose voltage amplitude is above 0V. In other words, a unipolar ADC cannot collect negative pressure.

[0003] Among them, as the number of acquisition channels increases, the complexity and cost of the multi-channel acquisition circuit also increase.

[0004] Therefore, there is an urgent need to provide a multi-channel acquisition circuit that can realize the acquisition of negative pressure by a unipolar ADC with lower complexity and cost. Summary of the invention

[0005] The embodiments of the present application provide a multi-channel acquisition circuit, a multi-channel acquisition method, a chip and a vehicle, which can realize the acquisition of negative pressure by a unipolar voltage acquisition module with lower complexity and cost, so as to at least partially solve the above-mentioned technical problems.

[0006] In order to achieve the above-mentioned purpose, according to the first aspect of the present application, a multi-channel acquisition circuit is provided, which includes a first multi-way selection module, a voltage polarity adjustment module and a voltage acquisition module. Each input end of the first multi-way selection module is respectively connected to a switch to be tested, and the first multi-way selection module is used to obtain the analog voltage to be tested of different switches to be tested in turn according to the acquisition timing; the voltage polarity adjustment module is used to adjust the voltage polarity of the analog voltage to be tested in turn according to the acquisition timing; the voltage acquisition module is used to convert the analog voltage to be tested after the voltage polarity adjustment into a corresponding digital voltage.

[0007] Optionally, the voltage polarity adjustment module includes a charge pump and a second multi-way selection module, the charge pump is used to output an adjustment voltage with the same polarity as the first voltage when the first voltage polarity identifiable by the voltage acquisition module is different from the second voltage polarity of the analog voltage to be measured; the second multi-way selection module is used to adjust the second voltage polarity in turn by adjusting the voltage according to the acquisition timing.

[0008] Optionally, the multi-channel acquisition circuit further includes a wetting current generating circuit, which is connected to the switch to be tested and is used to generate a wetting current to the switch to be tested.

[0009] Optionally, the wetting current generating circuit comprises a first wetting current generating module, and the first wetting current generating module is used to generate a wetting current for the switch to be tested on the power supply side.

[0010] Optionally, the first wetting current generating module includes a diode and a first current source, the anode of the diode is connected to the input voltage terminal; the input terminal of the first current source is connected to the cathode of the diode, and the output terminal of the first current source is connected to a corresponding switch to be tested.

[0011] Optionally, the wetting current generating circuit includes a second wetting current generating module, and the second wetting current generating module is used to generate a wetting current for the switch to be tested on the ground side.

[0012] Optionally, the second wetting current generating module includes a second current source, an input end of the second current source is connected to a ground-side switch to be tested, and an output end of the second current source is connected to the ground end.

[0013] Optionally, the wetting current generating circuit comprises a third wetting current generating module, and the third wetting current generating module is used to generate a wetting current to the switch to be tested.

[0014] Optionally, the third wetting current generating module includes a diode, a first current source and a second current source, the anode of the diode is connected to the input voltage terminal; the input terminal of the first current source is connected to the cathode of the diode, and the output terminal of the first current source is connected to a switch to be tested; the input terminal of the second current source is connected to a switch to be tested, and the output terminal of the second current source is connected to the ground terminal.

[0015] Optionally, the multi-channel acquisition circuit also includes a temperature acquisition module and a control module. The temperature acquisition module is used to convert the detected temperature of the voltage input port into a corresponding analog voltage to be tested and then transmit it to the first multi-way selection module; the control module is used to control the switch to be tested to disconnect when the temperature monitored by the temperature acquisition module exceeds a temperature threshold.

[0016] Optionally, the first multi-way selection module includes a first multi-way selection switch, the input end of the first multi-way selection switch is connected to the corresponding switch to be tested, the output end of the first multi-way selection switch is connected to the input end of the voltage acquisition module, and the first multi-way selection switch is used to alternately connect the connection between each input end and the output end according to the sampling timing.

[0017] Optionally, the second multi-way selection module includes a second multi-way selection switch, and the second multi-way selection switch operates synchronously with the first multi-way selection switch to synchronously connect a switch to be tested.

[0018] Optionally, the multi-channel acquisition circuit also includes a third multi-way selection module and a current acquisition module, the third multi-way selection module is used to obtain the analog voltage at both ends of the shunt connected in series with the switch to be tested according to the acquisition timing; the current acquisition module is used to obtain the corresponding digital current according to the difference between the analog voltages at both ends.

[0019] Optionally, the third multi-way selection module includes a third multi-way selection switch and a fourth multi-way selection switch, an input end of the third multi-way selection switch is connected to one end of the shunt, and an output end of the third multi-way selection switch is connected to an input end of the current acquisition module; an input end of the fourth multi-way selection switch is connected to the other end of the shunt, and an output end of the fourth multi-way selection switch is connected to the other input end of the current acquisition module.

[0020] Optionally, the multi-channel acquisition circuit also includes a multiplier and a first switch, the multiplier is connected between one of the output ends of the voltage acquisition module and the output ends of the current acquisition module and the control module, the multiplier is used to calculate the product of the digital voltage and the digital current, and the product is the power of the load connected in series with the switch to be tested; the first switch is connected between the other of the output ends of the voltage acquisition module and the output ends of the current acquisition module and the multiplier.

[0021] Optionally, the multi-channel acquisition circuit also includes a ninth switch, a second switch and a first self-test circuit, one end of the ninth switch is connected to the output end of the first multi-way selection module, and the other end of the ninth switch is connected to the input end of the voltage acquisition module; one end of the second switch is connected to the input end of the voltage acquisition module; the first self-test circuit is connected to the other end of the second switch, and the first self-test circuit is used to detect whether the voltage acquisition module is working normally.

[0022] Optionally, the multi-channel acquisition circuit also includes a fifth switch, a sixth switch, a seventh switch, an eighth switch and a second self-test circuit, one end of the fifth switch is connected to the output end of the third multi-way selection switch, and the other end of the fifth switch is connected to an input end of the current acquisition module; one end of the sixth switch is connected to the output end of the fourth multi-way selection switch, and the other end of the sixth switch is connected to the zero-one input end of the current acquisition module; one end of the seventh switch is connected to the other end of the fifth switch; one end of the eighth switch is connected to the other end of the sixth switch; the second self-test circuit is connected between the other end of the seventh switch and the other end of the eighth switch, and the second self-test circuit is used to detect whether the current acquisition module is working normally.

[0023] According to the second aspect of the present application, a multi-channel acquisition method is also provided, which includes: acquiring the analog voltages to be tested of different switches to be tested in turn according to the acquisition timing; adjusting the voltage polarity of the analog voltage to be tested in turn according to the acquisition timing; and converting the analog voltage to be tested after the voltage polarity adjustment into a corresponding digital voltage.

[0024] Optionally, the multi-channel acquisition method further includes: acquiring analog voltages at both ends of a shunt connected in series with the switch to be tested according to an acquisition timing; and obtaining a corresponding digital current according to a difference between the analog voltages at both ends.

[0025] Optionally, the multi-channel acquisition method further includes: obtaining the power of a load connected in series with the shunt according to the product of the digital voltage and the digital current; and determining an abnormal state of the load based on a comparison result of the power and energy consumption curves.

[0026] According to a second aspect of the present application, a chip is provided, the chip comprising the above-mentioned multi-channel acquisition circuit.

[0027] According to a third aspect of the present application, a vehicle is provided, the vehicle comprising the above-mentioned chip.

[0028] The multi-channel acquisition circuit, multi-channel acquisition method, chip and vehicle of the embodiments of the present application, through the first multi-way selection module, obtains the analog voltage to be tested of different switches to be tested in turn according to the acquisition timing, the voltage polarity adjustment module adjusts the voltage polarity of the analog voltage to be tested in turn according to the acquisition timing, and the voltage acquisition module is used to convert the analog voltage to be tested after the voltage polarity adjustment into the corresponding digital voltage, which can not only realize the collection of negative pressure by the unipolar voltage acquisition module, but also the multi-channels of the first multi-way selection module are turned on in turn, so only one voltage acquisition module is needed to perform time-sharing processing on the analog voltage to be tested transmitted by multiple channels, which reduces the complexity and cost of the multi-channel acquisition circuit.

[0029] Other features and advantages of the present application will be described in detail in the subsequent specific implementation section. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present application, and those skilled in the art can obtain other drawings based on these drawings without creative work.

[0031] In order to more completely understand the present application and its beneficial effects, the following description will be given in conjunction with the accompanying drawings, wherein the same figure numbers represent the same parts in the following description.

[0032] Figure 1 It is a principle block diagram of a switch detection circuit in the related technology.

[0033] Figure 2 is a circuit schematic diagram of a multi-channel acquisition circuit provided in an exemplary embodiment of the present disclosure.

[0034] Figure 3 is a principle block diagram of a multi-channel acquisition circuit provided in an exemplary embodiment of the present disclosure.

[0035] Figure 4 is a functional block diagram of a power management module provided in an exemplary embodiment of the present disclosure.

[0036] Figure 5 It is a schematic diagram of an application scenario of a chip provided in an exemplary embodiment of the present disclosure.

[0037] Figure 6 4 is a flow chart of a multi-channel acquisition method provided in an exemplary embodiment of the present disclosure.

[0038] Description of reference numerals:

[0039] 100. Multi-channel acquisition circuit;

[0040] 110. Power management module;

[0041] 111. Failure safety function module; 1111. Overvoltage protection circuit; 1112. Overcurrent protection circuit; 1113. Undervoltage protection circuit;

[0042] 112, voltage regulator module; 1121, front-end voltage regulator; 1122, analog low-dropout voltage regulator; 1123, digital low-dropout voltage regulator;

[0043] 121. a first multi-way selection module; 122. a voltage acquisition module; 123. a first self-test circuit;

[0044] 131. a third multi-channel selection module; 132. a current acquisition module; 133. a second self-test circuit;

[0045] 140. Voltage polarity adjustment module; 141. Charge pump; 142. Second multi-way selection module;

[0046] 150, wetting current generating circuit; 151, first wetting current generating module; 152, second wetting current generating module;

[0047] 160. control module; 161. communication interface; 162. temperature acquisition module; 163. filter circuit;

[0048] 200, MCU;

[0049] 300. switch driving circuit;

[0050] 400. Load. DETAILED DESCRIPTION

[0051] The technical solutions in the embodiments of the present application will be described clearly and completely below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present application.

[0052] In the related art, a vehicle-mounted unit ignition switch detection circuit is provided, such as Figure 1 As shown, the circuit includes a port protection circuit, a voltage divider circuit, an overvoltage protection circuit and a multi-mode selection circuit. The port protection circuit is connected in series between the vehicle end ignition switch and the voltage divider circuit, the voltage divider circuit is connected to the overvoltage protection circuit, and the overvoltage protection circuit is connected to the multi-mode selection circuit.

[0053] However, the above-mentioned on-board unit ignition switch detection circuit has the following shortcomings:

[0054] 1. It can only detect the switch status of the ignition switch (switch to be tested). When the load connected to the switch to be tested operates abnormally, it cannot provide timely feedback to the control unit, which means that it does not have the ability to diagnose system faults.

[0055] 2. It can only detect a single-channel switch to be tested, and is not suitable for application scenarios where multiple switches to be tested are to be tested.

[0056] 3. It can only detect the working state of the switch to be tested with positive voltage in the positive pressure control system, but cannot normally detect the working state of the switch to be tested with negative voltage in the negative pressure control system.

[0057] 4. Most of the components used are discrete components, which makes the circuit structure complicated during the application process and reduces the safety of the system.

[0058] This embodiment provides a multi-channel acquisition circuit 100. Figures 2 to 5 The multi-channel acquisition circuit 100 includes a first multi-channel selection module 121, a voltage polarity adjustment module 140 and a voltage acquisition module 122. The first multi-channel selection module 121 is used to obtain the analog voltages to be measured of different switches to be measured (SD1, SD2...) in turn according to the acquisition timing. The voltage polarity adjustment module 140 is used to adjust the voltage polarity of the analog voltage to be measured in turn according to the acquisition timing. The voltage acquisition module 122 is used to convert the analog voltage to be measured after the voltage polarity adjustment into the corresponding digital voltage.

[0059] It can be understood that the multi-channel acquisition circuit 100, multi-channel acquisition method, chip and vehicle of the embodiment of the present application, through the first multi-way selection module 121, obtains the analog voltage to be tested of different switches to be tested in turn according to the acquisition timing, the voltage polarity adjustment module 140 adjusts the voltage polarity of the analog voltage to be tested in turn according to the acquisition timing, and the voltage acquisition module 122 is used to convert the analog voltage to be tested after the voltage polarity adjustment into the corresponding digital voltage, which can not only realize the collection of negative pressure by the unipolar voltage acquisition module 122, but also the multiple channels of the first multi-way selection module 121 are turned on in turn, so only one voltage acquisition module 122 is needed to perform time-sharing processing on the analog voltage to be tested transmitted by multiple channels, which reduces the complexity and cost of the multi-channel acquisition circuit 100.

[0060] It should be noted that an input terminal of the first multi-way selection module 121 is connected to the corresponding switch to be tested and an output terminal of the voltage polarity adjustment module 140 , and the output terminal of the first multi-way selection module 121 is connected to the input terminal of the voltage acquisition module 122 .

[0061] The acquisition sequence is the order of acquiring the voltage and / or current of each switch to be tested, for example, the voltage and / or current of the nodes to be tested N1...Nn are acquired in sequence; or the voltage and / or current of the nodes to be tested Nn...N1 are acquired in sequence. The node to be tested is one end of the switch to be tested.

[0062] In some embodiments, the first multiple-way selection module 121 includes a first multiple-way selection switch MUX1, the input end of the first multiple-way selection switch MUX1 can be connected to the corresponding switch to be tested through a voltage input port, and the output end of the first multiple-way selection switch MUX1 is connected to the input end of the voltage acquisition module 122. The first multiple-way selection switch MUX1 can turn on the connection between each input end and the output end according to the sampling timing to obtain the analog voltage to be tested of different switches to be tested in turn.

[0063] In some embodiments, the voltage acquisition module 122 may include a voltage detection analog-to-digital converter VADC, the input end of the voltage detection analog-to-digital converter VADC is connected to the output end of the first multiplexer MUX1 to convert the analog voltage to be measured after the voltage polarity is adjusted into a corresponding digital voltage.

[0064] It should be noted that the first resistor R9, the second resistor R10, the ninth switch S9, the second switch S3 and the first self-test circuit 123 are optional in the multi-channel acquisition circuit 100, that is, these components may be absent, and the input end of the voltage detection analog-to-digital converter VADC is directly connected to the output end of the first multiplexer MUX1.

[0065] When these components are used, one end of the first resistor R9 is connected to the output end of the first multiplexer MUX1, the other end of the first resistor R9 is connected to one end of the second resistor R10, and the other end of the second resistor R10 is connected to the analog ground terminal AGND to form a voltage divider circuit to divide the output voltage of the first multiplexer MUX1.

[0066] Among them, the first self-test circuit 123 cooperates with the ninth switch S9 and the second switch S3 to check whether the voltage detection type analog-to-digital converter VADC is faulty. The self-test method is: first, the ninth switch S9 is disconnected and the second switch S3 is turned on. The first self-test circuit 123 outputs a stable voltage value through the analog power supply voltage Vanalog and the voltage divider circuit therein, and the voltage detection type analog-to-digital converter VADC is used to detect the stable voltage value. If the detection result is consistent with the known value, the voltage detection type analog-to-digital converter VADC is normal, otherwise it is faulty.

[0067] In some of the embodiments, the voltage polarity adjustment module 140 includes a charge pump 141 and a second multi-way selection module 142, the charge pump 141 is used to output an adjustment voltage with the same polarity as the first voltage when the first voltage polarity identifiable by the voltage acquisition module 122 is different from the second voltage polarity of the analog voltage to be measured; the second multi-way selection module 142 is used to adjust the second voltage polarity in turn by adjusting the voltage according to the acquisition timing.

[0068] It should be noted that the charge pump 141 can optionally use the analog power supply voltage Vanalog to provide itself with a working voltage. The charge pump 141 can output a positive voltage in a negative pressure control system. The output end of the charge pump 141 is connected to an input end of the second multiplexer module 142. An output end of the second multiplexer module 142 is connected to a voltage input port to raise the analog voltage to be measured to a positive voltage, thereby realizing that the unipolar ADC can also detect negative pressure.

[0069] In some embodiments, the second multiple-way selection module 142 may include a second multiple-way selection switch MUX4 , and the second multiple-way selection switch MUX4 may operate synchronously with the first multiple-way selection switch MUX1 to synchronously connect to the same voltage input port.

[0070] In some of the embodiments, the multi-channel acquisition circuit 100 further includes a wetting current generating circuit 150, and the wetting current generating circuit 150 is used to generate a wetting current to the switch to be tested connected to the switch to be tested.

[0071] It should be noted that when the switch to be tested has an oxide film, poor contact may easily occur at the connection between the voltage input port and the switch to be tested. The wetting current provided by the wetting current generating circuit 150 can improve or avoid such poor contact.

[0072] In some embodiments, the wetting current generating circuit 150 includes a first wetting current generating module 151, and the first wetting current generating module 151 is used to generate a wetting current for the switch to be tested on the power supply side.

[0073] It should be noted that the switch to be tested on the power supply side refers to the switch to be tested that is connected to the power supply.

[0074] In some embodiments, the first wetting current generating module 151 includes a diode D1 and a first current source IS1, the anode of the diode D1 is connected to the input voltage terminal; the input terminal of the first current source IS1 is connected to the cathode of the diode D1, and the output terminal of the first current source IS1 is connected to a corresponding switch to be tested.

[0075] In some embodiments, the wetting current generating circuit 150 includes a second wetting current generating module 152, and the second wetting current generating module 152 is used to generate a wetting current for the ground side switch to be tested. It should be noted that the ground side switch to be tested refers to a switch to be tested connected to the ground terminal.

[0076] In some embodiments, the second wetting current generating module 152 includes a second current source IS2 , an input end of the second current source IS2 is connected to a corresponding switch to be tested, and an output end of the second current source IS2 is connected to the ground end.

[0077] It should be noted that the ground terminal can be an analog ground terminal AGND. The first current source IS1 and the second current source IS2 can both be adjustable current sources, which can be in an off state (OFF) or can also provide an adjustable current, and the adjustable current range can be 1mA-15mA to improve or avoid the problem of poor contact.

[0078] In some embodiments, the wetting current generating circuit 150 includes a third wetting current generating module, and the third wetting current generating module is used to generate a wetting current for the switch to be tested.

[0079] In some embodiments, the third wetting current generating module includes a diode D1, a first current source IS1 and a second current source IS2, the anode of the diode D1 is connected to the input voltage terminal Vin; the input terminal of the first current source IS1 is connected to the cathode of the diode D1, and the output terminal of the first current source IS1 is connected to a switch to be tested; the input terminal of the second current source IS2 is connected to a switch to be tested, and the output terminal of the second current source IS2 is connected to the ground terminal.

[0080] It should be noted that the third wetting current generating module can generate a wetting current for the switch to be tested on the power supply side, and can also generate a wetting current for the switch to be tested on the ground side.

[0081] In some embodiments, such as Figure 2 , Figure 3 , Figure 4 As shown, the multi-channel acquisition circuit 100 also includes a temperature acquisition module 162 and a control module 160. The temperature acquisition module 162 is used to convert the detected temperature of the voltage input port into a corresponding analog voltage to be tested and then transmit it to the first multi-way selection module 121; the control module 160 is used to control the switch to be tested to disconnect when the temperature monitored by the temperature acquisition module 162 exceeds the temperature threshold.

[0082] It should be noted that the third switch S2 Figure 2 In the case where there is no third switch S2, the temperature acquisition module 162 can be directly connected to an input end of the first multi-way selection module 121 to continuously monitor the temperature of the voltage input port. In the case where there is a third switch S2, the temperature of the voltage input port can be selectively monitored.

[0083] Among them, when the temperature monitored by the temperature acquisition module 162 exceeds the temperature threshold, the control module 160 transmits the over-temperature information to the MCU200 through the communication interface 161, and the MCU200 can turn off the corresponding switch to be tested through the switch driving circuit 300 to prevent damage to the circuit or chip due to excessive temperature.

[0084] The fourth switch S1 is Figure 2 In the case where there is no fourth switch S1, the voltage input port can be directly connected to an input end of the first multi-way selection module 121 as a backup voltage detection channel. In the case where there is a fourth switch S1, the backup voltage detection channel can be selectively used.

[0085] In some of the embodiments, the multi-channel acquisition circuit 100 also includes a third multi-way selection module 131 and a current acquisition module 132. The third multi-way selection module 131 is used to obtain the analog voltage at both ends of the shunt connected in series with the switch to be tested according to the acquisition timing; the current acquisition module 132 is used to obtain the corresponding digital current according to the difference between the analog voltages at both ends.

[0086] It should be noted that the shunt is also connected in series with the load 400 , so the current flowing through the shunt is the same as the current flowing through the load 400 .

[0087] In some embodiments, the current acquisition module 132 includes a current detection analog-to-digital converter IADC, which performs a differential operation on the analog voltages at both ends of the shunt to obtain the difference between the analog voltages at both ends, and then obtains the current flowing through the shunt or the load 400 according to the resistance value of the shunt.

[0088] In some of the embodiments, the third multi-way selection module 131 may include a third multi-way selection switch MUX2 and a fourth multi-way selection switch MUX3, one input end of the third multi-way selection switch MUX2 is connected to one end of the shunt, the other input end of the fourth multi-way selection switch MUX3 is connected to the other end of the shunt, the output end of the third multi-way selection switch MUX2 is connected to an input end of the current acquisition module 132, and the output end of the fourth multi-way selection switch MUX3 is connected to the other input end of the current acquisition module 132.

[0089] It should be noted that, when the third multiplexer MUX2 and the fourth multiplexer MUX3 are turned on at the same time, the analog voltages at both ends of the same shunt can be transmitted to the two input ends of the current acquisition module 132 .

[0090] Among them, the third resistor R1, the fourth resistor R2, the fifth resistor R3, the sixth resistor R4, the seventh resistor R5, the eighth resistor R6, the ninth resistor R7, the tenth resistor R8, the fifth switch S5, the sixth switch S6, the seventh switch S7, the eighth switch S8 and the second self-test circuit 133 are Figure 2 is optional.

[0091] Among them, the third resistor R1, the fourth resistor R2, the fifth resistor R3, and the sixth resistor R4 are for adapting the resistance of the circuit, which are not essential and can be configured as needed.

[0092] The seventh resistor R5 and the ninth resistor R7 can form a voltage divider circuit to divide the output voltage of the third multiplexer MUX2, which is not necessary and can be configured as needed. The eighth resistor R6 and the tenth resistor R8 can form a voltage divider circuit to divide the output voltage of the fourth multiplexer MUX3, which is not necessary and can be configured as needed.

[0093] Among them, the second self-test circuit 133 cooperates with the fifth switch S5, the sixth switch S6, the seventh switch S7, and the eighth switch S8 to determine whether the current detection type analog-to-digital converter IADC has a fault. When performing a self-test, the fifth switch S5 and the sixth switch S6 are first disconnected, and the seventh switch S7 and the eighth switch S8 are turned on. The second self-test circuit 133 generates a stable current value, and the current detection type analog-to-digital converter IADC is used for detection. If the test value is the same as the current value, the current detection type analog-to-digital converter IADC is normal, otherwise the current detection type analog-to-digital converter IADC has a fault.

[0094] In some embodiments, such as Figure 2 As shown, the multi-channel acquisition circuit 100 further includes a multiplier CF1 and a first switch S4. The multiplier CF1 is connected between the output end of the voltage acquisition module 122 and the control module 160; the first switch S4 is connected between the output end of the current acquisition module 132 and the multiplier CF1.

[0095] It should be noted that the first switch S4 can control whether the multiplier CF1 performs power calculation or voltage calculation, that is, P or V. When the first switch S4 is disconnected, the multiplier CF1 can multiply the output voltage of the voltage acquisition module 122 by 1 for output, and can obtain the collected voltage; when the first switch S4 is turned on, the multiplier CF1 can multiply the output voltage of the voltage acquisition module 122 by the output current of the current acquisition module 132 to obtain the power of the load 400.

[0096] In some other embodiments, the multiplier CF1 is connected between the output end of the current acquisition module 132 and the control module 160 ; the first switch S4 is connected between the output end of the voltage acquisition module 122 and the multiplier CF1 .

[0097] It should be noted that, when the first switch S4 is disconnected, the multiplier CF1 can multiply the output current of the current acquisition module 132 by 1 and output it to obtain the collected current; when the first switch S4 is turned on, the multiplier CF1 can multiply the output current of the current acquisition module 132 by the output voltage of the voltage acquisition module 122 to obtain the power of the load 400.

[0098] In some embodiments, such as Figure 3 As shown, the multi-channel acquisition circuit 100 further includes an ESD (electrostatic discharge) protection circuit connected to each port to perform electrostatic protection on each port.

[0099] In some embodiments, such as Figure 3As shown, the multi-channel acquisition circuit 100 also includes a filter circuit 163 connected between the control module 160 and the voltage acquisition module 122 and / or the current acquisition module 132 to perform filtering processing such as removing burrs on the output signals of the voltage acquisition module 122 and / or the current acquisition module 132.

[0100] The control module 160 can also be used to determine whether an overvoltage or undervoltage occurs based on the comparison result between the output voltage of the voltage acquisition module 122 and the threshold voltage, and can also be used to determine whether an overcurrent occurs based on the comparison result between the output current of the current acquisition module 132 and the threshold current, and then report to the communication interface 161. Figure 5 The MCU 200 in the embodiment. The communication interface 161 may be an SPI interface or other interfaces. INT represents an interrupt interface.

[0101] In some embodiments, such as Figure 3 , Figure 4 As shown, the multi-channel acquisition circuit 100 also includes a power management module 110, which includes a fail-safe function module 111 and a voltage stabilization module 112, and the fail-safe function module 111 is connected to the voltage stabilization module 112. The overvoltage protection circuit 1111, the overcurrent protection circuit 1112, and the undervoltage protection circuit 1113 in the fail-safe function module 111 can perform corresponding overvoltage protection, overcurrent protection, and undervoltage protection on the input voltage Vin.

[0102] The voltage stabilization module 112 may include a front-end voltage stabilizer 1121, an analog low-dropout voltage stabilizer 1122 connected to the front-end voltage stabilizer 1121, and a digital low-dropout voltage stabilizer 1123. The front-end voltage stabilizer 1121 is used to stabilize voltage fluctuations. The analog low-dropout voltage stabilizer 1122 is used to generate an analog power supply voltage Vanalog to power analog circuits such as an analog-to-digital converter, a filter circuit 163, and a multi-channel acquisition circuit 100. The digital low-dropout voltage stabilizer 1123 is used to generate a digital power supply voltage Vdigital to power digital circuits such as a communication interface 161 and a control module 160 in the chip.

[0103] It should be noted that in Figure 5 In the embodiment, the switches to be tested can be SD1 and SD2, and the shunts can be R11 and R13, wherein one end of SD1 is connected to the power supply end Vpower, and the other end of SD1 is connected to one end of the shunt (R11), the node to be tested (N1), one end of the resistor R12, and the voltage input port (IADC). MUX3_0 ) and the other end of resistor R12 is connected to the voltage input port (VADC MUX1_0 ) is connected, the other end of the shunt (R11) is connected to the load 400, the voltage input port (IADC MUX2_0The control end of SD1 is connected to the switch driving circuit 300.

[0104] The control end of SD2 is connected to the switch driving circuit 300, one end of SD2 is connected to the analog ground terminal AGND, and the other end of SD2 is connected to one end of the shunt (R13), the node to be measured (Nn), one end of the resistor R14 and the voltage input port (IADC). MUX3_n ) and the other end of resistor R14 is connected to the voltage input port (VADC MUX1_n ) is connected, the other end of the shunt (R13) is connected to the load 400, the voltage input port (IADC MUX2_n )connect.

[0105] The resistors R12 and R14 are optional. The capacitor C1 is also optional. SD1 is a switch to be tested on the power supply side, and SD2 is a switch to be tested on the ground side.

[0106] VADC MUX1_0 ...VADC MUX1_n IADC represents the port connected to each input terminal of the first multi-way selection module 121. MUX2_0 ...IADC MUX2_n IADC represents the ports connected to the input terminals of the third multiplexer MUX2. MUX3_ 0...IADC MUX3_n Indicates the ports connected to the input terminals of the fourth multiplexer MUX3.

[0107] In summary, the present application can realize the detection function of the switching status of multiple switches to be tested in the positive pressure and negative pressure control systems, as well as the energy consumption and fault conditions of the connected load 400. At the same time, safety functions such as overvoltage protection, undervoltage protection, overcurrent protection, and overtemperature detection are designed to improve system safety.

[0108] 1. Compared with the related art, the switch detection circuit can only detect the switch state. When the load 400 connected to the switch is in a fault state, it cannot be detected and intervened in time. The load 400 will continue to be in a fault state, which may cause logical confusion in the overall system, damage to system components and other problems. Therefore, it does not have the ability to diagnose system faults.

[0109] The design of this application uses a current detection type ADC and a voltage detection type ADC to detect not only the working state of the switch to be tested, but also the energy consumption of the load 400 connected to the switch. By monitoring the energy consumption curve and the energy consumption value, it can be determined whether the load 400 is in a fault state. Therefore, this application not only realizes the switch state detection function, but also adds the circuit fault diagnosis function, thereby improving the system safety.

[0110] 2. Compared with the related technology, the switch detection circuit can only detect the switch state of the switch to be tested in the positive pressure control system, but is not suitable for detecting the working state of the switch to be tested in the negative pressure control system. Moreover, the oxide film at the interface of the switch to be tested is not processed, which may affect the switch performance.

[0111] The related art uses a bipolar ADC to detect negative pressure, but the cost of the bipolar ADC is relatively high. Therefore, the present application adds a charge pump 141 that can be selected according to the working mode at the switch detection interface. The charge pump 141 raises the voltage at the unipolar ADC input port to the positive voltage range, thereby achieving the purpose of unipolar ADC detecting negative pressure.

[0112] Furthermore, in order to avoid the influence of the oxide film on the operating performance of the switch, the present application adds a wetting current generating circuit 150 and a corresponding ESD protection circuit 130 at the input port.

[0113] According to the above design, this application can realize low-cost detection of the working status of the switch to be tested in the positive pressure and negative pressure control systems, and also avoids the influence of the oxide film at the switch interface on the working performance of the switch.

[0114] 3. Compared with the related art that can only detect the working status of a single switch to be tested, when there are multiple switches to be tested in the system, the use of this related art will cause problems such as complex circuits, numerous components, and high circuit costs.

[0115] Aiming at the working environment of multi-channel input detection, the present application designs a combination of a multi-channel selection switch and an analog-to-digital converter, and detects the working status of multiple switches to be tested by polling the voltage value at each input pin of the multi-channel selection switch through the control module 160.

[0116] By combining a single charge pump 141 with a multi-way selection switch and coordinating with the system polling timing (sampling timing), the single charge pump 141 can raise the voltage of multiple input ports of the analog-to-digital converter, thereby realizing the detection of the working status of multiple switches to be tested in the negative pressure control system, which can effectively reduce the system cost.

[0117] According to the above design, normal detection of multiple switches to be tested can be completed, which effectively reduces the system cost and simplifies the system circuit.

[0118] 4. Compared with the related art, which is all independent and separate components, further affecting the system security. This application integrates the power management module 110, the multi-way selection switch, the analog-to-digital converter, the filter circuit 163, the control module 160 and other components, which can effectively avoid the peripheral circuit interference problem existing in the independent and separate components, and further improve the system security.

[0119] In some embodiments, this embodiment provides a chip, which includes the multi-channel acquisition circuit 100 mentioned above. It should be noted that the multi-channel acquisition circuit 100 is Figure 5 It is presented in the form of a chip.

[0120] It can be understood that since the chip of the embodiment of the present application includes the above-mentioned multi-channel acquisition circuit 100, it is also possible to obtain the analog voltage to be tested of different switches to be tested in turn according to the acquisition timing through the first multi-way selection module 121, and the voltage polarity adjustment module 140 adjusts the voltage polarity of the analog voltage to be tested in turn according to the acquisition timing. The voltage acquisition module 122 is used to convert the analog voltage to be tested after the voltage polarity adjustment into the corresponding digital voltage. Not only can the unipolar voltage acquisition module 122 realize the collection of negative pressure, but also the multiple channels of the first multi-way selection module 121 are turned on in turn. Therefore, only one voltage acquisition module 122 is needed to perform time-sharing processing on the analog voltage to be tested transmitted through multiple channels, which reduces the complexity and cost of the multi-channel acquisition circuit 100.

[0121] In some embodiments, the present embodiment provides a multi-channel acquisition method, such as Figure 6 As shown, the multi-channel acquisition method includes the following steps:

[0122] Step S10: acquiring the analog voltages to be tested of different switches to be tested in turn according to the acquisition timing.

[0123] Step S20: adjusting the voltage polarity of the analog voltage to be measured in turn according to the acquisition timing.

[0124] Step S30: converting the analog voltage to be tested after voltage polarity adjustment into a corresponding digital voltage.

[0125] It can be understood that the multi-channel acquisition method of the embodiment of the present application uses the first multi-way selection module 121 to obtain the analog voltage to be tested of different switches to be tested in turn according to the acquisition timing, and the voltage polarity adjustment module 140 adjusts the voltage polarity of the analog voltage to be tested in turn according to the acquisition timing. The voltage acquisition module 122 is used to convert the analog voltage to be tested after the voltage polarity adjustment into the corresponding digital voltage. Not only can the unipolar voltage acquisition module 122 realize the collection of negative pressure, but also the multiple channels of the first multi-way selection module 121 are turned on in turn. Therefore, only one voltage acquisition module 122 is needed to perform time-sharing processing on the analog voltage to be tested transmitted through multiple channels, which reduces the complexity and cost of the multi-channel acquisition circuit 100.

[0126] In some of the embodiments, the multi-channel acquisition method further includes: acquiring analog voltages at both ends of a shunt connected in series with the switch to be tested according to an acquisition timing; and obtaining a corresponding digital current according to a difference between the analog voltages at both ends.

[0127] It should be noted that the current and / or current detected when the switch to be tested is disconnected and connected are different, based on which the switch state of the switch to be tested can be determined.

[0128] In some of the embodiments, the multi-channel acquisition method further includes: obtaining the power of the load 400 connected in series with the shunt according to the product of the digital voltage and the digital current; and determining the abnormal state of the load 400 based on the comparison result of the power and energy consumption curves.

[0129] It should be noted that the energy consumption curve can be pre-made according to the operating conditions of the load 400, and when the comparison results of the power and energy consumption curves differ greatly, it means that the load 400 is in an abnormal state, thereby realizing the fault diagnosis function; or, when the comparison results of the power and energy consumption curves differ slightly, it means that the load 400 is not in an abnormal state, that is, it is in a normal state.

[0130] In some embodiments, the present embodiment provides a vehicle, which includes the above chip. The vehicle may be a fuel vehicle, a plug-in hybrid vehicle, or a new energy vehicle, etc., which is not specifically limited in the present disclosure.

[0131] It can be understood that since the vehicle of the embodiment of the present application includes the above-mentioned chip, it is also possible to obtain the analog voltage to be tested of different switches to be tested in turn according to the acquisition timing through the first multi-way selection module 121, and the voltage polarity adjustment module 140 adjusts the voltage polarity of the analog voltage to be tested in turn according to the acquisition timing. The voltage acquisition module 122 is used to convert the analog voltage to be tested after the voltage polarity adjustment into the corresponding digital voltage, which can not only realize the collection of negative pressure by the unipolar voltage acquisition module 122, but also the multiple channels of the first multi-way selection module 121 are turned on in turn, so only one voltage acquisition module 122 is needed to perform time-sharing processing on the analog voltage to be tested transmitted by multiple channels, which reduces the complexity and cost of the multi-channel acquisition circuit 100.

[0132] In the description of this application, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more features. In the description of this application, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0133] In the above embodiments, the description of each embodiment has its own emphasis. For parts that are not described in detail in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0134] The embodiments, implementation methods and related technical features of the present application can be combined and replaced with each other without conflict.

[0135] The above are only preferred embodiments of the present application and do not constitute any form of limitation to the present application. However, any simple modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present application without departing from the content of the technical solution of the present application are still within the scope of the technical solution of the present application.

Claims

1. A multi-channel acquisition circuit, characterized in that: The multi-channel acquisition circuit comprises: A first multi-channel selection module, each input end of which is connected to a switch to be tested, and the first multi-channel selection module is used to obtain the analog voltages to be tested of different switches to be tested in turn according to an acquisition timing sequence; A voltage polarity adjustment module, the voltage polarity adjustment module is used to adjust the voltage polarity of the analog voltage to be measured in turn according to the acquisition timing; A voltage acquisition module, the voltage acquisition module is used to convert the analog voltage to be measured after the voltage polarity is adjusted into a corresponding digital voltage; The voltage polarity adjustment module comprises: A charge pump, wherein the charge pump is used to output an adjustment voltage having the same polarity as the first voltage when the polarity of the first voltage identifiable by the voltage acquisition module is different from the second voltage polarity of the analog voltage to be measured; A second multi-way selection module, wherein the second multi-way selection module is used to adjust the polarity of the second voltage in turn through the adjustment voltage according to the acquisition timing.

2. The multi-channel acquisition circuit according to claim 1, characterized in that: The multi-channel acquisition circuit further includes a wetting current generating circuit, which is connected to the switch to be tested and is used to generate a wetting current to the switch to be tested.

3. The multi-channel acquisition circuit according to claim 2, characterized in that: The wetting current generating circuit comprises a first wetting current generating module, and the first wetting current generating module is used to generate a wetting current for the switch to be tested at the power supply side.

4. The multi-channel acquisition circuit according to claim 3, characterized in that: The first wetting current generating module comprises: A diode, wherein an anode of the diode is connected to the input voltage terminal; A first current source, wherein an input end of the first current source is connected to the cathode of the diode, and an output end of the first current source is connected to a corresponding switch to be tested.

5. The multi-channel acquisition circuit according to claim 2, characterized in that: The wetting current generating circuit comprises a second wetting current generating module, and the second wetting current generating module is used to generate a wetting current for the switch to be tested at the ground side.

6. The multi-channel acquisition circuit according to claim 5, characterized in that: The second wetting current generating module comprises a second current source, an input end of the second current source is connected to the switch to be tested at a ground side, and an output end of the second current source is connected to the ground end.

7. The multi-channel acquisition circuit according to claim 2, characterized in that: The wetting current generating circuit comprises a third wetting current generating module, and the third wetting current generating module is used to generate a wetting current to the switch to be tested.

8. The multi-channel acquisition circuit according to claim 7, characterized in that: The third wetting current generating module comprises: A diode, wherein an anode of the diode is connected to the input voltage terminal; a first current source, wherein an input end of the first current source is connected to a cathode of the diode, and an output end of the first current source is connected to a switch to be tested; A second current source, wherein an input terminal of the second current source is connected to the switch to be tested, and an output terminal of the second current source is connected to a ground terminal.

9. The multi-channel acquisition circuit according to claim 2, characterized in that: The multi-channel acquisition circuit also includes: A temperature acquisition module, the temperature acquisition module is used to convert the detected temperature of the voltage input port into a corresponding analog voltage to be measured and transmit the analog voltage to the first multiplex selection module; A control module, wherein the control module is used to control the switch to be tested to be disconnected when the temperature monitored by the temperature acquisition module exceeds a temperature threshold.

10. The multi-channel acquisition circuit according to claim 1, characterized in that: The first multi-way selection module includes a first multi-way selection switch, the input end of the first multi-way selection switch is connected to the corresponding switch to be tested, the output end of the first multi-way selection switch is connected to the input end of the voltage acquisition module, and the first multi-way selection switch is used to alternately conduct the connection between each input end and the output end according to the acquisition timing.

11. The multi-channel acquisition circuit according to claim 10, characterized in that: The second multi-way selection module includes a second multi-way selection switch, and the second multi-way selection switch operates synchronously with the first multi-way selection switch to synchronously connect to the switch to be tested.

12. The multi-channel acquisition circuit according to claim 1, characterized in that: The multi-channel acquisition circuit also includes: A third multi-way selection module, the third multi-way selection module is used to obtain the analog voltage at both ends of the shunt connected in series with the switch to be tested according to the acquisition timing; A current acquisition module is used to obtain a corresponding digital current according to the difference between the analog voltages at both ends.

13. The multi-channel acquisition circuit according to claim 12, characterized in that: The third multi-way selection module comprises: a third multi-way selection switch, wherein an input end of the third multi-way selection switch is connected to one end of the shunt, and an output end of the third multi-way selection switch is connected to an input end of the current acquisition module; A fourth multi-way selection switch, wherein an input end of the fourth multi-way selection switch is connected to the other end of the shunt, and an output end of the fourth multi-way selection switch is connected to the other input end of the current acquisition module.

14. The multi-channel acquisition circuit according to claim 12, characterized in that: The multi-channel acquisition circuit also includes: A multiplier, the multiplier being connected between an output terminal of the voltage acquisition module and an output terminal of the current acquisition module and a control module, the multiplier being used to calculate the product of the digital voltage and the digital current, the product being the power of a load connected in series with the switch to be tested; A first switch is connected between the other of the output end of the voltage acquisition module and the output end of the current acquisition module and the multiplier.

15. The multi-channel acquisition circuit according to claim 1, characterized in that: The multi-channel acquisition circuit also includes: a ninth switch, one end of which is connected to the output end of the first multi-way selection module, and the other end of which is connected to the input end of the voltage acquisition module; a second switch, wherein one end of the second switch is connected to the input end of the voltage acquisition module; A first self-test circuit, wherein the first self-test circuit is connected to the other end of the second switch, and the first self-test circuit is used to detect whether the voltage acquisition module works normally.

16. The multi-channel acquisition circuit according to claim 13, characterized in that: The multi-channel acquisition circuit also includes: a fifth switch, wherein one end of the fifth switch is connected to the output end of the third multi-way selection switch, and the other end of the fifth switch is connected to an input end of the current acquisition module; a sixth switch, wherein one end of the sixth switch is connected to the output end of the fourth multi-way selection switch, and the other end of the sixth switch is connected to the zero and one input ends of the current acquisition module; a seventh switch, one end of the seventh switch being connected to the other end of the fifth switch; an eighth switch, one end of the eighth switch being connected to the other end of the sixth switch; A second self-test circuit, wherein the second self-test circuit is connected between the other end of the seventh switch and the other end of the eighth switch, and the second self-test circuit is used to detect whether the current acquisition module works normally.

17. A multi-channel acquisition method, characterized in that: The multi-channel acquisition method is applied to the multi-channel acquisition circuit according to any one of claims 1 to 16, and the multi-channel acquisition method includes: Acquire the analog voltages to be tested of different switches to be tested in turn according to the acquisition timing; Adjusting the voltage polarity of the analog voltage to be measured in turn according to the acquisition timing; The analog voltage to be measured after voltage polarity adjustment is converted into a corresponding digital voltage.

18. The multi-channel acquisition method according to claim 17, characterized in that: The multi-channel acquisition method further comprises: Acquire analog voltages at both ends of a shunt connected in series with the switch to be tested according to the acquisition timing; The corresponding digital current is obtained according to the difference between the analog voltages at both ends.

19. The multi-channel acquisition method according to claim 18, characterized in that: The multi-channel acquisition method further comprises: Obtaining the power of a load connected in series with the shunt according to the product of the digital voltage and the digital current; Based on the comparison results of the power and energy consumption curves, the abnormal state of the load is determined.

20. A chip, characterized in that: The chip includes the multi-channel acquisition circuit described in any one of claims 1 to 16.

21. A vehicle, characterized in that: The vehicle comprises the chip of claim 20.

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