Automobile power supply system

Abstract

The invention relates to a motor vehicle power supply system (1) for converting a battery voltage ranging between 6 V DC and 16 V DC into a DC voltage ranging between 3 V and 12 V, in particular between 3.3 V and 12 V, said motor vehicle power supply system (1) comprising: an input (2) for receiving a voltage of a battery (3), said voltage of the battery (3) is referred to as a first voltage (U1),-a first buck converter (4) for receiving the first voltage (U1) via the input (2) and for down-converting the first voltage into a second voltage (U2) if said first voltage (U1) is at least 12V,-a boost converter (7) for converting the second voltage (U2) into a second voltage (U2) if said first voltage (U1) is at least 12V, the invention relates to a converter (1) comprising:-a boost converter (2) connected to the input (2) and configured to convert a first voltage (U1) to a third voltage (U3) higher than the first voltage (U1), and-a multi-phase dc-dc converter (5) having at least two channels (5a, 5b), said multi-phase dc-dc converter (5) configured to activate and deactivate the channels of the multi-phase dc-dc converter independently of the other.

Description

[0001] This invention relates to an automotive power supply system for converting a battery voltage ranging from 6V DC to 16V DC to a DC voltage ranging from 3V to 12V, particularly from 3.3V to 12V. The automotive power supply system includes: an input terminal for receiving a battery voltage, referred to as a first voltage; and a first buck converter for receiving the first voltage via the input terminal and, if the first voltage is at least 12V, for converting the first voltage down to a second voltage ranging from 3V to 12V, particularly from 3.3V to 12V, and for providing the second voltage to a first output terminal.

[0002] In the automotive industry, the use of sensors such as radar, lidar, and cameras is becoming increasingly important. The primary use cases for these sensors are related to Advanced Driver Assistance Systems (ADAS), which are crucial for achieving autonomous driving. Because these sensors serve this critical use case, their functionality must be fail-safe and / or redundant. Therefore, the power supply for these sensors must also meet fail-safe functionality and / or redundancy requirements to satisfy, for example, Automotive Safety Integrity Levels (ASIL), such as ASIL-B / D.

[0003] The object of this invention is to provide an automotive power supply system with a high level of reliability. This object is achieved by an automotive power supply system of the type described above, comprising: a boost converter connected to an input terminal and configured to convert a first voltage to a third voltage higher than the first voltage, the boost converter providing the third voltage to a second output terminal, wherein the third voltage is fed to a second buck converter configured to convert the third voltage to a second voltage and provide the second voltage to a first output terminal; and a multiphase DC-DC converter having at least two channels, the multiphase DC-DC converter being configured to activate and deactivate its channels independently of another, wherein the multiphase DC-DC converter includes a first buck converter as one of the at least two channels and includes a second buck converter as the other of the at least two channels. The automotive power supply system also includes a switching circuit for receiving and monitoring a first voltage. This switching circuit is connected to a multiphase DC-DC converter to switch the activation of a channel with a first buck converter and a channel with a second buck converter. The switching circuit is configured to activate and deactivate at least some channels of the multiphase DC-DC converter based on the voltage level of the first voltage: if the first voltage is equal to or exceeds a switching threshold Uth, which is a predetermined value within the range of 6V to 12V, deactivate the channel with the second buck converter and activate the channel with the first buck converter to convert the first voltage to a second voltage and provide the second voltage to the first output; and if the voltage level is below the switching threshold Uth, deactivate the channel with the first buck converter and activate the channel with the second buck converter to convert a third voltage to a second voltage and provide the second voltage to the first output. For example, this can be based on the design of the circuit feeding the first voltage into the switching device (e.g., as...). Figure 2 The disclosed voltage divider determines the value of the switching threshold Uth, and the switching device can be implemented as, for example, as... Figure 2 The disclosed transistor circuit.

[0004] The battery voltage does not need to reach 16V. Any voltage in the range of 6V to 16V will be suitable for this automotive power supply system. The multiphase converter does not need to have more than two channels. It can be a two-phase, three-phase, four-phase, etc., converter. The boost converter can supply voltages higher than 12V, for example, by compensating for voltage losses based on the forward voltage of a diode connected in series with the output of the boost converter.

[0005] In the automotive industry, DC-DC converters with multiple channels / phases in a single package have been uncommon in the past. This invention utilizes these new converters that allow independent control of each channel / phase. This enables redundancy. It is possible that at any given time, only one channel of the dual converter is active. For example, normally, phase 1 is active. This can be supplied by a battery with, for example, a KL30eFuse voltage. Since this voltage can drop below the switching threshold Uth in the event of a battery failure, this would render the buck converter of the first channel unusable, thus allowing the second channel to be supplied by the 48V output of the dual boost converters. This feature provides additional fault protection. An example of a multiphase DC-DC converter is integrated, for instance, into an Infineon chip named “TLD55012QVXUMA1,” which includes a dual synchronous buck controller with an SPI interface.

[0006] Preferably, the first buck converter and the second buck converter are configured to provide a second voltage equal to 5V, 6V, or 12V, or in the range of 6V to 12V.

[0007] Advantageously, the channels of the multiphase DC-DC converter can be digitally adjusted to determine the conversion to the second voltage and the level of the second voltage.

[0008] Preferably, the channels of the multiphase DC-DC converter can be adjusted in an analog manner to determine the conversion to the second voltage and the level of the second voltage.

[0009] For example, it can be set according to Figure 2 The ratio of resistors MU1 and MU2, along with the corresponding control logic stored in the IC, determines the conversion. Analog and digital regulation may also be combined.

[0010] Advantageously, the third voltage level ranges between 45V and 50V, and specifically equals 48V.

[0011] Preferably, the multiphase DC-DC converter includes a microcontroller connected to a switching circuit to control the activation / deactivation of at least two channels based on signals provided by the switching circuit.

[0012] Advantageously, the switching circuit is implemented as an analog circuit comprising a first transistor circuit and a second transistor circuit, each transistor circuit having an output that is provided to a microcontroller to determine the switching operation of the corresponding channel, wherein the transistor circuits are logically coupled in such a way that a first voltage is provided to the first transistor circuit and the output of the first transistor circuit is fed as an input to the second transistor circuit, thereby ensuring that the output of the analog circuit will trigger the activation of only one of the two channels.

[0013] Preferably, the second transistor circuit includes a locking mechanism designed to maintain the level of the output signal of the second transistor circuit when switching from the first channel to the second channel, thus independently of the continuous activation of the second channel and the continuous deactivation of the first channel caused by the first voltage level, until the switching circuit is reset, for example, by cutting off the power supply to the switching circuit.

[0014] Furthermore, the present invention also relates to an automotive electronic system comprising an automotive power supply system according to the present invention and a first load connected to a second voltage, the first load comprising at least one of the following: a light-emitting sensor system; a radar sensor system; a camera sensor system for light-emitting; a radar or camera; a seismic motion sensor; an inertial measurement unit; an ultrasonic sensor; a rain sensor; a light sensor; and a temperature sensor.

[0015] Optionally, the automotive electronic system also includes a second load connected to a third voltage, the second load including at least one of the following: an electric power steering system, an air conditioning system, a heated windshield, an active chassis, an engine cooling system, a PTC heater, and an electric turbocharger.

[0016] In the following sections, exemplary and non-limiting embodiments are discussed to further demonstrate the invention, as illustrated in the accompanying drawings, which show: Figure 1 An exemplary schematic diagram of an automotive power supply system according to the present invention, Figure 2 according to Figure 1 An exemplary embodiment of a vehicle power supply, the embodiment including details of the circuitry of the vehicle power supply.

[0017] In the following figures, unless otherwise explicitly depicted, the same reference numerals refer to the same features. Reference numerals are for informational purposes only and do not define the scope of the claims.

[0018] Figure 1An automotive power supply system 1 is shown, which converts a battery voltage ranging from 6V DC to 16V DC to a DC voltage ranging from 3V to 12V, particularly from 3.3V to 12V. The automotive power supply system 1 includes: an input terminal 2 for receiving the voltage of a battery 3, referred to as a first voltage U1; and a first buck converter 4 for receiving the first voltage U1 via the input terminal 2. When the first voltage U1 is equal to or higher than a switching threshold Uth, the first buck converter 4 converts the first voltage U1 down to a second voltage U2 ranging from 3V to 12V, particularly from 3.3V to a maximum voltage of 12V. This converted voltage is referred to as the second voltage U2 and is provided to a second output terminal 7a. With a diode arranged between the first output terminal 7a and the buck converter 4, the output voltage of the buck converter 4 can also be higher than 12V when the first voltage U1 is higher than 12V, to compensate for the forward voltage drop of the diode and facilitate obtaining 12V at the second output terminal 7a. The same considerations also apply to the second buck converter 6, which will be discussed below.

[0019] The automotive power supply system 1 also includes a boost converter 7 connected to input 2 and configured to convert a first voltage U1 to a third voltage U3. The third voltage U3 is higher than the first voltage U1. The boost converter 7 is configured to provide the third voltage U3 to a second output 7b. Furthermore, the third voltage U3 is fed as input to a second buck converter 6, which is configured to convert the third voltage U3 to a second voltage U2 and provide the second voltage U2 to a first output 7a.

[0020] To avoid simultaneous activation of both buck converters 4 and 6, the automotive power supply system 1 further includes a multiphase DC-DC converter 5 having at least two channels 5a and 5b. The multiphase DC-DC converter 5 is configured to activate and deactivate its channels independently of the other. The multiphase DC-DC converter 5 includes a first buck converter 4 as one of the at least two channels 5a and 5b, and a second buck converter 6 as the other of the at least two channels 5a and 5b. The automotive power supply system 1 also includes a switching circuit 8 for receiving and monitoring a first voltage U1. The switching circuit 8 is connected to the multiphase DC-DC converter 5 to switch between channel 5a with the first buck converter 4 and channel 5b with the second buck converter 6. The activation of the switching circuit 8 is configured to activate and deactivate at least some channels 5a, 5b of the multiphase DC-DC converter according to the voltage level of the first voltage U1: when the first voltage U1 is equal to or exceeds the switching threshold Uth, which is a predetermined value in the range of 6V to 12V, the channel 5b with the second buck converter 6 is deactivated, and the channel 5a with the first buck converter 4 is activated to convert the first voltage U1 to the second voltage U2 and provide the second voltage U2 to the first output terminal 7a; and when the voltage level is lower than the switching threshold Uth, the channel 5a with the first buck converter 4 is deactivated, and the channel 5b with the second buck converter 6 is activated to convert the third voltage U3 to the second voltage U2 and provide the second voltage U2 to the first output terminal 7a.

[0021] The first buck converter 4 and the second buck converter 6 can be configured to provide a second voltage U2 equal to 5V, 6V, or 12V, or in the range between 6V and 12V. Channels 5a and 5b of the multiphase DC-DC converter 5 can be digitally adjusted to determine the conversion to the second voltage U2 and the level of the second voltage U2. Alternatively or additionally, it is possible that channels 5a and 5b of the multiphase DC-DC converter 5 can be adjusted analogically to determine the conversion to the second voltage U2 and the level of the second voltage U2. For example, it can be set according to... Figure 2 The ratio of resistors MU1 and MU2, along with the corresponding control logic stored in the IC, determines the conversion. Analog and digital regulation may also be combined.

[0022] The third voltage level U3 can range between 45V and 50V, specifically equal to 48V.

[0023] Furthermore, the present invention also relates to an automotive electronic system comprising an automotive power supply system according to any one of the preceding claims and a first load 9 connected to a second voltage U2, the first load 9 comprising at least one of: a light-emitting sensor system; a radar sensor system; a camera sensor system for light-emitting; a radar or camera; a seismic motion sensor; an inertial measurement unit; an ultrasonic sensor; a rain sensor; a light sensor; and a temperature sensor.

[0024] The automotive electronic system also includes a second load 10 (see...) Figure 1 The second load is connected to the third voltage U3, and the second load 10 includes at least one of the following: electric power steering system, air conditioning, heated windshield, active chassis, engine cooling system, PTC heater, electric turbocharger.

[0025] Figure 2 It shows according to Figure 1 An exemplary embodiment of an automotive power supply includes details of the circuitry for that power supply. The multiphase DC-DC converter 5 includes a microcontroller IC connected to a switching circuit 8 to control the activation / deactivation of at least two channels 5a, 5b based on signals provided by the switching circuit 8. (See from...) Figure 2 As can be seen, the switching circuit 8 is implemented as an analog circuit, which includes a first transistor circuit DG1 and a second transistor circuit DG2. Each transistor circuit has outputs DG1out and DG2out, which are provided to the microcontroller IC to determine the switching operation of the corresponding channels 5a and 5b. The transistor circuits DG1 and DG2 are logically coupled in the following way: a first voltage U1 is provided to the first transistor circuit DG1, and the output DG1out of the first transistor circuit DG1 is fed as an input to the second transistor circuit DG2, thereby ensuring that the outputs DG1out and DG2out of the analog circuit will trigger the activation of only one of the two channels 5a and 5b.

[0026] Possibly, the second transistor circuit DG2 includes a locking mechanism DG2lock, which is designed to maintain the level of the output signal DG2out of the second transistor circuit DG2 during switching from the first channel 5a to the second channel 5b. This ensures that the second channel 5b remains continuously activated and the first channel 5a remains continuously deactivated independently of the first voltage level U1, until the switching circuit 8 is reset, for example, by cutting off its power supply. This circuit ensures that there is no repeated back-and-forth oscillation during phase modulation.

[0027] Observe more closely Figure 2The electronic components shown are now described in other words as exemplary parts of the invention: The switching circuit 8 receives, for example, 5V as an operating voltage from the internal LDO of the multiphase DC-DC converter 5. The input of the first phase (i.e., the level of the first voltage U1) is continuously monitored by special transistor circuitry. When the voltage of the first input drops below a certain value, the second phase is switched on and takes over the power supply to the participating load. This makes the system redundant and particularly suitable for ADAS and functional safety requirements.

[0028] The first voltage U1 is tapped and set to 5V via a voltage divider. Current is limited by a resistor in the cross branch and connected to the gate of the subsequent transistor in the first transistor circuit DG1. A PNP transistor can be used as an inverter. As long as the first voltage U1 has a switching threshold Uth or higher, the voltage in the voltage divider is close to 5V, and the transistor is not turned on. Therefore, there is a potential of 0V at the output of the inverter (Buck_12V_SET2). This signal at the transistor's output is connected to the VSET2 pin of the buck converter and modulated from 0V to 0%.

[0029] Once the first voltage U1 falls below the switching threshold Uth, the voltage divider voltage also decreases and the PNP transistor turns on. Once the 1.5V threshold is reached at the VSET2 pin, the second channel of the dual buck converter is modulated to 100%. This circuit provides additional reliability. The voltage drop of the first voltage U1 does not negatively affect the voltage level of the second channel 5b, because this second channel is connected to a stable, higher voltage, namely the output of the boost converter 7.

[0030] The reference numerals MI1 to MI4 refer to resistors used to measure the corresponding currents. Reference numerals MU1 and MU2 refer to voltage dividers comprising two resistors used to measure the corresponding voltages. The controller IC controls channels 5a and 5b by controlling transistor circuits Q1 to Q4 to ensure that the second voltage U2 can be provided to output terminal 7a. Coils L1 and L2, together with capacitors C1 and C2, smooth the outputs of channels 5a and 5b.

[0031] Furthermore, the outputs of both buck converters 4 and 6 can be configured to deliver only the higher voltage to the output. This is achieved via two Schottky diodes on the right side of the diagram. Additionally, capacitors are implemented to store the voltage during system phase switching.

[0032] In cases where digital modulation is possible, the capacitor can be skipped or made much smaller (because digital modulation is much faster when transitioning from a low to a high state). The buck converter can be activated within 0.8 ms, so the capacitance only needs to be large enough to store energy during the time until the buck converter is activated.

[0033] Additionally, it is possible to lock the first channel 5a into a disabled state to avoid channel switching. For this purpose, the circuit DG2lock is implemented as follows: main transistor ( Figure 2 The main transistor (the one that receives U_lock in DG2) can be of type PNP. This main transistor is configured to always be on. Therefore, phase 1 will be on. Once the battery voltage drops and phase 2 is activated, the voltage U_lock will rise and become positive, and the PNP transistor will be deactivated, causing the output buck_12V_set1 to drop to 0, which corresponds to 0% modulation on phase 1.

[0034] This circuit ensures that there is no "back and forth" during phase modulation.

[0035] This invention is not limited to the embodiments shown, but is defined by the full scope of the claims. Various aspects of the invention or its embodiments may also be adopted and combined with each other. Any reference numerals in the claims are exemplary and are used only to facilitate a more convenient review, not to limit the scope of the claims.

Claims

1. An automotive power supply system (1) for converting a battery voltage ranging from 6V DC to 16V DC to a DC voltage ranging from 3V to 12V, particularly from 3.3V to 12V, the automotive power supply system (1) comprising: - Input terminal (2), the input terminal is used to receive the voltage of the battery (3), the voltage of the battery (3) is referred to as the first voltage (U1). - A first buck converter (4), which is used to receive the first voltage (U1) via the input terminal (2), and when the first voltage (U1) is at least 12V, to convert the first voltage down to a second voltage (U2) in the range of 3V to 12V, particularly between 3.3V and 12V, and to provide the second voltage (U2) to the first output terminal (7a). Its features are, The vehicle power supply system (1) also includes - A boost converter (7), connected to the input terminal (2) and configured to convert the first voltage (U1) into a third voltage (U3) higher than the first voltage (U1), the boost converter (7) providing the third voltage (U3) to a second output terminal (7b), wherein the third voltage (U3) is fed to a second buck converter (6), the second buck converter (6) being configured to convert the third voltage (U3) into a second voltage (U2) and provide the second voltage (U2) to the first output terminal (7a), and - A multiphase DC-DC converter (5) having at least two channels (5a, 5b), wherein the multiphase DC-DC converter (5) is configured to activate and deactivate the channels of the multiphase DC-DC converter independently of the other, wherein the multiphase DC-DC converter (5) * Includes the first buck converter (4) as one of the at least two channels (5a, 5b), and * Includes the second buck converter (6) as another channel of the at least two channels (5a, 5b). - A switching circuit (8) for receiving and monitoring the first voltage (U1), the switching circuit (8) being connected to the multiphase DC-DC converter (5) to switch the activation of the channel (5a) having the first buck converter (4) and the channel (5b) having the second buck converter (6), wherein the switching circuit (8) is configured to perform the activation and deactivation of at least some channels (5a, 5b) of the multiphase DC-DC converter according to the voltage level of the first voltage (U1): * When the first voltage (U1) is equal to or exceeds the switching threshold Uth, which is a predetermined value within the range of 6V and 12V, the channel (5b) with the second buck converter (6) is deactivated, and the channel (5a) with the first buck converter (4) is activated to convert the first voltage (U1) to the second voltage (U2) and provide the second voltage (U2) to the first output terminal (7a). * When the voltage level is lower than the switching threshold Uth, the channel (5a) with the first buck converter (4) is deactivated, and the channel (5b) with the second buck converter (6) is activated to convert the third voltage (U3) into the second voltage (U2) and provide the second voltage (U2) to the first output terminal (7a).

2. An automotive power supply system (1), wherein a first buck converter and a second buck converter (4, 6) are configured to provide a second voltage (U2) equal to 5V, 6V or 12V or in the range of 6V to 12V.

3. The automotive power supply system (1) according to claim 1 or 2, wherein the channels (5a, 5b) of the multiphase DC-DC converter (5) are digitally adjustable to determine the conversion to the second voltage (U2) and the level of the second voltage (U2).

4. The automotive power supply system (1) according to any one of the preceding claims, wherein the channels (5a, 5b) of the multiphase DC-DC converter (5) are tunable in an analog manner to determine the conversion to the second voltage (U2) and the level of the second voltage (U2).

5. The automotive power supply system (1) according to any one of the preceding claims, wherein the third voltage level (U3) ranges between 45V and 50V, particularly equal to 48V.

6. The automotive power supply system (1) according to any one of the preceding claims, wherein the multiphase DC-DC converter (5) includes a microcontroller (IC) connected to the switching circuit (8) to control the activation / deactivation of the at least two channels (5a, 5b) based on signals provided by the switching circuit (8).

7. The automotive power supply system (1) according to claim 6, wherein the switching circuit (8) is implemented as an analog circuit comprising a first transistor circuit (DG1) and a second transistor circuit (DG2), each transistor circuit having an output (DG1out, DG2out) provided to the microcontroller (IC) to determine the switching operation of the corresponding channel (5a, 5b), wherein the transistor circuits (DG1, DG2) are logically coupled in such a way that the first voltage (U1) is provided to the first transistor circuit (DG1) and the output (DG1out) of the first transistor circuit (DG1) is fed as an input to the second transistor circuit (DG2), thereby ensuring that the output (DG1out, DG2out) of the analog circuit will trigger the activation of only one of the two channels (5a, 5b).

8. The automotive power supply system (1) according to claim 7, wherein the second transistor circuit (DG2) includes a locking mechanism (DG2lock) designed to maintain the level of the output signal (DG2out) of the second transistor circuit (DG2) when switching from the first channel (5a) to the second channel (5b), thereby causing continuous activation of the second channel (5b) and continuous deactivation of the first channel (5a) independently of the first voltage level (U1), until the switching circuit is reset, for example, by cutting off the power supply to the switching circuit (8).

9. An automotive electronic system comprising an automotive power supply system according to any one of the preceding claims and a first load (9) connected to the second voltage (U2), the first load (9) comprising at least one of: a light-emitting sensor system; a radar sensor system; a camera sensor system for light-emitting; a radar or camera; a seismic motion sensor; an inertial measurement unit; an ultrasonic sensor; a rain sensor; a light sensor; and a temperature sensor.

10. The automotive electronic system of claim 9, wherein the automotive electronic system further comprises a second load (10) connected to the third voltage (U3), the second load (10) comprising at least one of: an electric power steering system, an air conditioning system, a heated windshield, an active chassis, an engine cooling system, a PTC heater, an electric turbocharger, and the second load typically having a 48V power supply.

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