WO2010052187A2

WO2010052187A2 - Driver circuit for producing a load voltage

Info

Publication number: WO2010052187A2
Application number: PCT/EP2009/064457
Authority: WO
Inventors: Jürgen Kellner; Jürgen Stuber
Original assignee: Continental Automotive Gmbh
Priority date: 2008-11-05
Filing date: 2009-11-02
Publication date: 2010-05-14
Also published as: JP5362021B2; JP2012507964A; WO2010052187A3; CN102204102A; CN102204102B; DE102008055956A1

Abstract

A driver circuit (100) for producing a load voltage for feeding a load (104), in particular a load of a vehicle, wherein the driver circuit (100) comprises a supply voltage source (U_B) for providing a supply voltage, an intermediate storage unit (101) for intermediately storing electrical energy, wherein the intermediate storage unit (101) is coupled to a supply voltage source for providing the electrical energy, and a driver unit (105) to which the electrical energy can be fed by way of the intermediate storage unit (101) as necessary, whereby the load voltage can be provided to the load (104) in the event of a failure of the supply voltage.

Description

description

Driver circuit for providing a load voltage

The invention relates to a driver circuit for providing a load voltage for supplying a load, in particular a load of a vehicle.

Furthermore, the invention relates to a vehicle.

The invention further relates to a method for providing a load voltage for supplying a load, in particular a load of a vehicle.

Moreover, the invention relates to a program element.

The invention further relates to a computer-readable storage medium.

Modern motor vehicles form complex systems of hardware and software. For the mechatronic system automotive regulation and control a large number verschiedenster STEU ^¬ ergerate is used. The totality of all control devices forms a highly networked system based on different bus systems or communication devices. The heterogeneity of hardware and software with such a system is highly complex. The power supply auto Mobi ^¬ len is a critical component especially with comfortable furnishings. Thus, for example, in vehicles different dene loads, such as relays, other control units or motors with power or voltage supplied to ^¬ to activate it and to keep active. Such relays require some voltage to be activated and low voltage to stay active. To supply a voltage to a relay, for example, a driver circuit can be used. Conventional semiconductor driver circuits can provide high voltages. If the supply voltage of these driver circuits drops, then However, the driver circuit switched off, since such driver circuits can usually only be operated at high voltages.

The invention has for its object to provide the Spannungsver ^¬ supply for a load, in particular a load of a vehicle.

This object is achieved by the subject matter of the independent patent claims. Advantageous embodiments of the present invention are described in the dependent claims.

According to a first aspect of the invention, a driver circuit is provided for providing a load voltage for supplying a load, in particular a load of a vehicle, wherein the driver circuit comprises a supply voltage source for providing a supply voltage, a buffer unit for buffering electrical energy the buffer unit is coupled to a supply voltage source for supplying the electrical energy, and has a driver unit, which can be supplied with the electrical energy as required by means of the buffer unit, whereby the load voltage can be provided to the load when the supply voltage drops.

In accordance with another aspect of the invention, there is provided a vehicle that provides a driver circuit having the features described above for providing a load voltage for supplying a load of a vehicle.

According to yet another exemplary embodiment of the invention, a method for providing a load voltage for supplying a load, in particular a load of a vehicle, is provided, wherein a supply voltage through a

Supply voltage source is stored, electrical energy is stored in a buffer unit, wherein the buffer unit with a supply supply voltage source is coupled to provide the electrical energy, and wherein the electrical energy is supplied to a drive unit, whereby the load at a drop in the supply voltage, the load voltage can be provided.

In a computer-readable storage medium according to an exemplary embodiment of the present invention, a program for providing a load voltage for supplying a load, in particular a load of a vehicle, is stored, which program, when executed by a processor, controls the method steps described above. carried out.

Em program element (computer program element) according to an exemplary embodiment of the present invention to provide a load voltage for supplying a load, particularly a load of a vehicle, the above-described ^¬ NEN method steps (or controls or leads them through) when is executed by a processor.

Exemplary embodiments of the present invention can be realized both by means of a computer program, that is to say a software, and by means of one or more special electrical circuits, that is to say in hardware, or in any hybrid form, that is to say by means of software components and hardware components.

According to an exemplary embodiment of the invention, a driver circuit for a vehicle system (for example, an automobile or motor vehicle) is provided, which supplies a load with a load voltage. The driver circuit can also be used for various electrical devices. Such a driver circuit contains an internal elec- πsche supply voltage source for providing electrical ^¬ shear energy for powering various loads in the vehicle or can be coupled to such an external voltage source. The voltage source may be For example, to a battery act. Electric energy in this context is to be understood as meaning both electrical and electrochemical energy. A load can be, for example, a relay, another control unit or motors here. An intermediate storage unit is connected to a supply voltage source. The supply voltage source may be the supply voltage source of the driver circuit or an external supply voltage source, for example a decoupled battery. While a proper or normal operation of the supply voltage source ^¬ the intermediate storage unit is loaded. This may be, for example, a capacitor or a battery. By charging, the buffer unit provides electrical or electrochemical energy. A driver unit may be connected to the intermediate unit. This drive unit, the electric power provided by the Zwischenspei ^¬ chereinheit with a drop in supply voltage or failure of the supply voltage source, to supply the load with a load voltage. In this case, the supply voltage that has dropped off can be supplied to the load as a load voltage. This can ensure that the load can be supplied even with a drop in the supply voltage at least with a low voltage. For example, a voltage of 1.5 or 2 V may be sufficient to keep relays active.

In the following, preferred embodiments of the driver circuit will be described. These also apply to the procedure, the vehicle, the program element and the computer-readable storage medium.

In case of failure of the supply voltage source, the load voltage may be smaller than the supply voltage in a proper operation of the supply voltage source. When the supply voltage drops, the load voltage may follow the drop in the supply voltage. By using a driver unit in the event of a failure of the supply Voltage source, however, the load voltage can be greater than the currently existing supply voltage and smaller than the supply voltage in a proper operation of the supply voltage source, which can be prevented that at the loads, such as relays, no voltage is present. The driver unit can serve to supply the load with the currently available supply voltage.

The load voltage may be greater than or equal to a load-dependent predetermined threshold. This threshold can be determined from the voltage required for a given load. The buffer unit and the driver unit can be dimensioned accordingly.

The driver unit may be a low-voltage side driver unit. For low voltages this driver unit can be used. Usual driver units were turned off at low voltages. The driver unit may be a ground switching element. This can be used as a positive switching element.

A release unit may be provided which may be coupled between the buffer unit and the driver unit. This release unit can release the power supply for the driver unit, that is, it can close a connection between the buffer unit and the driver ^¬ unit. This allows control of the driver unit.

The driver circuit may further comprise a high voltage side driver unit, wherein the high voltage side driver unit, the electrical energy can be supplied, and wherein the high voltage side driver unit of the load can provide the load voltage. This makes it possible for the high-voltage-side driver unit to provide a load voltage at high voltages and for low voltages at which this driver unit is disconnected. is switched off or fails due to the low voltage, the low-voltage side driver unit provides the load voltage. The high voltage side driver unit may be a positive switching element. In this context, providing can mean that connections between the load and the supply voltage are closed by the driver units, or that the driver units switch to allow corresponding connections.

Furthermore, a microcontroller may be provided, which is coupled to the high-voltage side driver unit and the release unit in order to control these. In this way, an optimal and efficient control of the driver units and the provision of the load voltage is made possible.

The driver units preferably have switches. This can be a simple and inexpensive way to implement the driver units. In particular, the switches may be transistors, for example MOSFETs, or integrated driver devices.

In addition, additional embodiments of the vehicle will be described. These also apply to the driver circuit, to the process, to the program element and to the computer-readable storage medium.

The vehicle may be, for example, an automobile (for example a motor vehicle, in particular a passenger car or a lorry). But it is also possible, the erfmdungsgemaße driver circuit in a train, in a

Aircraft (for example, an airplane, a helicopter or a zeppelin) or to implement in a ship.

It should be noted that embodiments of the inventions fertil with reference to different subject invention be ^¬ wrote were. In particular, some embodiments of the invention are described with Vorπchtungsanspruchen and other embodiments of the invention with method claims. ben. However, it will be readily apparent to one skilled in the art upon reading this application that, unless explicitly stated otherwise, in addition to a combination of features associated with a type of subject matter, any combination of features may be contemplated Types of Erfmdungsgegenstände belong.

Further advantages and features of the present invention will become apparent from the following exemplary description of currently preferred embodiments. The individual figures of the drawing of this application are merely to be regarded as schematic and not to scale.

FIG. 1 shows a schematic driver circuit for a

Vehicle according to an exemplary embodiment of the invention.

Figure 2 shows an exemplary embodiment of a driver scarf ^¬ processing of FIG. 1

FIG. 3 shows a possible voltage curve of a load without the use of a driver circuit according to the invention.

FIG. 4 shows possible voltage characteristics in a system using a driver circuit according to the invention.

The illustrations in the figures are schematic and not to scale. The same or similar components in different figures are provided with the same reference numerals.

There are various approaches to compensate for a voltage drop in a driver circuit as discrete solutions with

Charge pump supply or DC / DC boost converters. Furthermore, discrete solutions such as bipolar transistors can be used, but these are not compatible with an output current in the can be operated rich of more than 500 mA. In addition, such solutions do not always meet the specifications of vehicle manufacturers. It is therefore desirable to provide a driver circuit that can provide a satisfactory voltage supply to a load.

1 shows an exemplary embodiment of a driver circuit 100 according to the invention, which provides a voltage supply for a load of a vehicle. In this exemplary embodiment, the driver circuit has a supply voltage source U _B , for example a battery. An intermediate storage unit 101 is coupled to the supply voltage source U _B. During the normal voltage operation, the latch unit 101 is charged. Furthermore, in normal operation, a high-voltage side driver unit

102, which is connected to the supply voltage source U _B operated. The driver unit 102 is controlled by a microcontroller 103, wherein the microcontroller 103 and the driver unit 102 are connected. The microcontroller 103 controls the driver unit 102 so that a load 104 is supplied with the supply voltage. The load 104 is connected to the driver unit 102. The driver unit 102 may ^{comprise a} transistor, for example a MOSFET. Here, the gate terminal is connected to the microcontroller, the dram connection with the supply voltage source U _B and the source terminal to the load 104. Furthermore, the driving circuit 100 to a low side driving pure ^¬ integrated 105th The driver unit 105 is connected on the one hand via a release unit 106 to the latch 101, on the other hand, the driver unit 105 with the supply voltage source U _B and further with the load 104 verbun ^¬ the. The driver unit 105 may also comprise a transistor, for example a MOSFET, wherein the drain terminal is connected to the supply voltage source U _B , the gate terminal to the release unit 106 and the source terminal to the load 104. The release unit 106 is further connected to the microcontroller. In a normal voltage operation, the high-voltage side Driver unit 102 is used to supply the output or the load 104 with the supply voltage. At the same time, the buffer unit 101 is loaded. In case of a drop or failure of the supply voltage or the supply voltage source U _B , the high-voltage side driver unit 102 is turned off due to a too low voltage. The release unit 106 is switched by the microcontroller 103 so that the release unit 106 turns on the connection between the latch unit 101 and the low-voltage side drive unit 105. The input of the low voltage side driver unit 105 is then energized by the latch unit 101 whose voltage level is higher than that of the supply voltage. The low-voltage side driver unit 105 is activated because the voltage between gate and source

Connection is high enough. The virtual grounding potential of this system is the output to the load. When the supply voltage returns to a normal level, for example 12 V, the high-voltage side driver unit 102 is turned on again. The virtual Erdungsspan- voltage level is then close to the supply voltage level and the low side driver unit 105 is again switched from ^¬. By this system it is achieved that the voltage across the load drops with the supply voltage, but does not fall below a certain level, since at a drop in the supply voltage, the low-voltage side drive unit 105 is turned on to supply the load with a voltage. For example, this voltage can drop to 2V. The load may, for example, be a relay which may remain activated even at a low voltage. In modem vehicle architectures, it is desired that the semiconductor driver outputs be available for a short time, even during very low supply voltages, for example during start-up. At the same time Treiberleistungsfahigkeit grows to high from ^¬ gang stromen, for example, more than 500 inA. Conventional integrated semiconductor drivers are only able to operate the output at a higher voltage. To exits like For example, to operate the ignition (Terminal 15) or the starter (Terminal 50), it is necessary to operate the semiconductor driver circuits throughout.

FIG. 2 shows a further exemplary embodiment of a driver circuit 100 according to the invention. From this driver circuit, it can be seen that the latch unit 101 may have, for example, a capacitor 111 which is charged during normal operation. The intermediate storage unit has in this case further ver ^¬ different resistors and diodes. In the event of a drop in the supply voltage, the microcontroller 103 controls a switch 120, for example a transistor, in the release unit 106, as a result of which a further switch 121, for example a MOSFET, switches through in the enable unit so that the low-voltage-side driver unit 105 is supplied with a voltage from the Buffer unit 101 is supplied. The latch unit 101 may be a Batte ^¬ rie further provides an electrochemical energy. The low-voltage side driver unit 105 then provides a minimum voltage to the load 104. As shown in FIG. 2, the high voltage side driver unit 102 may include a switch 125 instead of a transistor.

In Fig. 3, a possible voltage waveform of the supply voltage is shown. The supply voltage U _B drops in this case to the value U ₃ , and remains at this value over a longer period. As a result of this waste, a conventional driver circuit was switched off without the use of a driver circuit according to the invention and an external load was no longer supplied.

FIG. 4 shows a voltage curve with the use of a driver circuit according to the invention. The supply voltage U _B and the output voltage U _ou t _/ which is the ^¬ supplied leads are 12 V, as well as the voltage U _z in the buffer. At the time t1, the supply voltage U _B drops below 4V, the output voltage U _out follows. At the time t2, the supply voltage U _B rises again to 12V, as does the output voltage U _out following it. The voltage U _z in the buffer also drops at the time t1, since it is no longer charged by the supply voltage U _B , but drops only to 8V at time t2. This ensures a power supply for the low-voltage side driver unit. The low-voltage side driver unit is turned on by the release unit 106, which is already turned on by the microcontroller at a time tθ. Of the

Can tθ time both lie in time before the drop of the supply voltage U _B the time tl, but can also be at the same time at the time tl. If the release unit activates the low-voltage side driver unit before the supply voltage drops, it is achieved that the voltage at the input to the load is intercepted in good time. This may be necessary for some loads, but for other loads it may also be sufficient to activate the low-voltage side driver unit only at time t1. Activation in the time between t1 and t2 is also possible.

It should be noted that the embodiments described here represent only a limited selection of possible embodiments of the invention. So it is possible to combine the features of individual embodiments in a suitable manner, so that the skilled man ^¬ with the explicit embodiment variants here a variety of different embodiments disclosed as obvious are to be considered.

Claims

claims

A driver circuit (100) for providing a load voltage for supplying a load (104), in particular a load of a vehicle, the driver circuit (100) comprising:

A supply voltage source (U _B ) for providing a supply voltage;

A buffer unit (101) for buffering electrical energy, wherein the buffer unit

(101) is coupled to a supply voltage source for providing the electrical energy; and

• a drive unit (105) which, if necessary, the electric energy can be fed to means of Zwischenspei ^¬ chereinheit (101), whereby the load (104), the load voltage is ready-adjustable to a drop in the supply voltage.

2. driver circuit (100) according to claim 1, wherein in case of failure of the supply voltage source (U _B ), the load voltage is smaller than the supply voltage in proper operation of the supply voltage source (U _B ).

3. Driver circuit (100) according to claim 1 or 2, wherein the load voltage is greater than or equal to a load-dependent predetermined threshold.

4. Driver circuit (100) according to any one of claims 1 to 3, wherein the driver unit (105) is a mederspannungssei- term driver unit.

5. Driver circuit (100) according to one of the preceding claims, wherein a release unit (106) is provided, which is coupled between the buffer unit (101) and the driver unit (105).

6. Driver circuit (100) according to one of the preceding claims, wherein the driver circuit (100) has a high-voltage side driver unit (102), wherein the high-voltage side driver unit (102), the supply voltage can be supplied, and wherein the high-voltage side driver unit ( 102) provides the load voltage to the load (104).

7. Driver circuit (100) according to claim 6, wherein a microcontroller (103) is provided, which is coupled to the high voltage ^¬ tion side driver unit (102) and the release unit (106) to control them.

8. Driver circuit (100) according to one of the preceding claims, wherein the driver units (102, 105) comprise switches.

9. driver circuit (100) according to claim 6, wherein the switches are transistors, in particular MOSFETs, or integrated driver chips.

10. A vehicle comprising a driver circuit according to claim 1 for providing a load voltage for supplying a load of a vehicle.

11. The vehicle of claim 10, selected from a group consisting of an automobile, a passenger car, a truck, a bus, a train, an aircraft and a ship.

12. A method for providing a load voltage for supplying a load, in particular a load of a vehicle, the method comprising: • providing a supply voltage through a supply voltage source (U _B );

Caching of electrical energy in a buffer unit (101), wherein the buffering unit (101) is coupled to a supply voltage source for providing the electrical energy; and

• supplying the electric power to a driving unit (105), whereby the load (104), the load voltage can be provided with a drop in versor ^¬ supply voltage.

13. A computer readable storage medium in which a program for providing a load voltage for supplying a load, particularly a load of a vehicle, vomit ^¬ chert, wherein the program, when executed by a processor, for performing or controlling the method according to one of Claims 11 to 14 is set up.

14. A program element for providing a load voltage for supplying a load, in particular a load of a vehicle, wherein the program element, when executed by a processor, for implementing or controlling the method according to any one of claims 11 to 14 is arranged.