FR3038470A1 - POWER SUPPLY CIRCUIT - Google Patents

Abstract

The present invention relates to an electrical supply circuit (1) of an electronic control unit (3), said circuit (1) comprising: - a first connection terminal (B1) intended to be connected to a first source of power supply associated with a first voltage level, - a second connection terminal (B2) intended to be connected to a second power source associated with a second voltage level different from the first voltage level, - a third connection terminal ( B3) intended to be connected to the electronic control unit; - a first switching element (5a) arranged to turn on the first (B1) and the third (B3) connection terminal or to interrupt the conduction between the first (B1) and B1) and the third (B3) connection terminal, - a second switching element (5b) arranged to turn on the second (B2) and the third (B3) connection terminal or to interrupt the conduction between e the second (B2) and the third (B3) connection terminal, - a control device (7) configured to control the conduction or off-conduction of the first (5a) and the second (5b) switching element in function of the configuration of the electronic control unit (3).

Description

POWER SUPPLY CIRCUIT

The present invention relates to the field of electrical circuits for supplying electronic control units, in particular on-board electronic control units in motor vehicles. The control units are used to control different equipment. In the case of a motor vehicle, this equipment corresponds in particular to the sensors used in the vehicle. However, depending on the type of sensor, the supply voltage required for the operation of the sensor may vary so that the control unit used to power the sensor will be connected, either directly to a battery delivering for example 13 V, or to an electric bus delivering for example a DC voltage of 5 V and said control unit will be configured accordingly. However, this means that several types of control units are respectively associated with a type of sensor requiring a different supply voltage.

Thus, in order to reduce the manufacturing cost related in particular to the supply management of the control units, a solution must be found that makes it possible to reduce the number of different control units. For this purpose, the subject of the present invention is an electrical circuit for powering an electronic control unit, said circuit comprising: a first connection terminal intended to be connected to a first power source associated with a first level; voltage, - a second connection terminal intended to be connected to a second power source associated with a second voltage level different from the first voltage level, - a third connection terminal intended to be connected to the control unit electronic, - a first switching element arranged to turn on the first and third connection terminal or to interrupt the conduction between the first and the third connection terminal, - a second switching element arranged to turn on the second and the third third connection terminal or interrupt the conduction between the second and the third connection terminals - A control device configured to control the conduction or out of conduction of the first and second switching element according to the configuration of the electronic control unit.

Thus, by controlling the first or second switching element from the controller, the power supply needed for the control unit can be configured so that only one type of control unit can be used. for several types of power supplies.

According to another aspect of the present invention, said control unit is configured to supply a first type of sensor requiring a first supply voltage or a second type of sensor requiring a second supply voltage.

According to a further aspect of the present invention, the control device comprises a microcontroller or any other type of programmable logic electronic circuit such as gate networks in situ (FPGA).

According to an additional aspect of the present invention, the first voltage level is a voltage of 5V DC and the second voltage level corresponds to a voltage delivered by a battery, in particular 13 V.

According to another aspect of the present invention, the first and the second switching element comprise at least one transistor and a bias resistor of the transistor.

According to a further aspect of the present invention, the first switching element comprises: - a first NPN transistor whose base is connected via a first resistor to a fourth connection terminal intended to be connected to the control device, the transmitter is connected to ground and the collector is connected to a first connection point via a second resistor, - a second PNP transistor whose base is connected to the first connection point, the collector is connected to the third control terminal via a third resistor and the emitter is connected to the first connection terminal, the first connection point is connected to the first connection terminal via a fifth resistor, and the second switching element comprises - a third NPN type transistor whose base is connected via a sixth resistor to a fifth connection terminal for connection to the communication device. the transmitter is connected to ground and the collector is connected to a second connection point via a seventh resistor, - a fourth PNP transistor whose base is connected to the second connection point, the collector is connected to the third control terminal via an eighth resistor and the emitter is connected to the second connection terminal, the second connection terminal being connected to the second connection point via a tenth resistor and a diode.

According to an additional aspect of the present invention, the emitter of the second PNP transistor is connected to the first connection terminal via a fourth resistor and / or the emitter of the fourth PNP transistor is connected to the second connection terminal. via a ninth resistance.

According to an additional aspect of the present invention, the values of the fourth resistance and the tenth resistance are between 0 and 100 Ω.

According to another aspect of the present invention, the third control terminal is connected to ground via a capacitor.

According to a further aspect of the present invention, the control device comprises a first control output connected to the fourth connection terminal and a second control output connected to the fifth connection terminal. Other features and advantages of the invention will appear in the description which will now be made, with reference to the accompanying drawings which show, by way of indication but not limitation, possible embodiments.

In these drawings: FIG. 1 represents a simplified diagram of an electric supply circuit of an electronic control unit according to the present invention; FIG. 2 represents a simplified diagram of a variant of the circuit of FIG. 1; - Figure 3 shows a detailed circuit diagram of the power supply circuit of an electronic control unit according to the present invention.

In these figures, the same reference numerals designate elements having an identical function.

The following achievements are examples. Although the description refers to one or more embodiments, this does not necessarily mean that each reference relates to the same embodiment, or that the features apply only to a single embodiment. Simple features of different embodiments may also be combined to provide other embodiments.

In the description which follows, generally denotes:

The term "MOSFET" corresponds to the acronym "Metal Oxide Semiconductor Field Effect Transistor" and corresponds to an insulated gate field effect transistor;

The term "FPGA" corresponds to the English acronym Field programmable gate array and designates a network of programmable gates in situ;

The terms "NPN" and "PNP" correspond to a type of transistors and in particular to a type of junction used in the transistor. An NPN transistor comprises two P-N junctions with a common P-type layer and a PNP transistor comprises two P-N junctions with a common N-type layer. An N-type layer corresponds to a layer with an excess of electrons and a P-type layer corresponds to a layer with an excess of holes.

FIG. 1 represents a simplified diagram of an electric supply circuit 1 of an electronic control unit 3. The electric supply circuit 1 comprises a first connection terminal B1 and a second connection terminal B2. The first connection terminal B1 is intended to be connected to a first power source (not shown) delivering a first voltage level, for example a battery delivering a voltage of 13 V. The second connection terminal B2 is intended to be connected to a second power source (not shown) delivering a second voltage level different from the first voltage level, for example a DC supply bus delivering a voltage of 5V. The electric supply circuit 1 also comprises a first switching element 5a associated with the first connection terminal B1 and a second switching element 5b associated with the second connection terminal B2. The first switching element 5a is arranged to electrically conduct the first connection terminal B1 with a third connection terminal B3 or to interrupt the electrical conduction between the first connection terminal B1 and the third connection terminal B3. The second switching element 5b is arranged to electrically conduction the second connection terminal B2 with the third connection terminal B3 or to interrupt the electrical conduction between the second connection terminal B2 and the third connection terminal B3. The first 5a and second 5b switching elements are controlled by a control device 7 such as a microcontroller. The third terminal B3 is intended to be connected to a power supply input of an electronic control unit 3. The third terminal B3 is also connected to ground via a capacitor C.

Moreover, the electric supply circuit 1 can be used to supply the control device 7 or other electronic circuits 11. In this case, the diagram of FIG. 1 is modified as shown in FIG. of the control device 7 and / or the electronic circuit 11 is realized via an adaptation circuit 13 comprising two resistors denoted Rs and Rp to enable the voltage supplied to the control device 7 and / or to the electronic circuit 11 to be adapted. Rs is arranged between the power supply input of the control device 7 and / or the electronic circuit 11 and the third connection terminal B3 while the resistor Rp is arranged between the power supply input of the control device 7 and / or the electronic circuit 11 and the mass 9.

The realization of the first 5a and second 5b switching elements will now be described in detail from Figure 3 which shows a detailed diagram of the power supply circuit.

The first switching element 5a comprises a first NPN type transistor Q1 whose base is connected to a fourth connection terminal B4, intended to be connected to the control device 7, via a first resistor RI. The emitter of the first transistor Q1 is connected to ground 9 and the collector is connected to a first connection point PI via a second resistor R2.

The first switching element 5a also comprises a second PNP-type transistor Q2 whose base is connected to the first connection point P1. The collector of the second transistor Q2 is connected to the third control terminal B3 via a third resistor R3 which is a bias resistor of the second transistor Q2. The emitter of the second transistor Q2 is connected to the first connection terminal B1 via a fourth resistor R4. The first connection point P1 is also connected to the first connection terminal B1 via a fifth resistor R5.

Thus, when a voltage is applied at the fourth connection terminal B4 by the control device 7, for example a microcontroller, the first transistor Q1 turns on so that the first connection point P1 is connected to the ground 9 The second transistor Q2 is therefore in a blocking state equivalent to an open switch between the first B1 and the third B3 connection terminals.

When no voltage is applied at the fourth connection terminal B4 by the controller 7, the first transistor Q1 is in a blocking state so that the first terminal B1 provides a current at the first connection point. Pl which makes the second transistor Q2 passing so that the third connection terminal B3 is connected to the first connection terminal B1 via the resistors R4 and R3.

The second switching element 5b comprises a third transistor NPN type Q3 whose base is connected to a fifth connection terminal B5, intended to be connected to the control device 7, for example a microcontroller, via a sixth resistor R6. The emitter of the third transistor Q3 is connected to ground 9 and the collector is connected to a second connection point P2 via a seventh resistor R7.

The second switching element 5b also comprises a fourth PNP Q4 transistor Q4 whose base is connected to the second connection point P2. The collector of the fourth transistor Q4 is connected to the third control terminal B3 via an eighth resistor R8 which is a bias resistor of the fourth transistor Q4. The emitter of the fourth transistor Q4 is connected to the second connection terminal B2 via a ninth resistor R9. The second connection terminal B2 is also connected to the second connection point P2 via a tenth resistor RIO and a diode D.

The operation of the second switching element 5b is similar to the operation of the first switching element 5a so that when a voltage is applied by the control device 7, for example a microcontroller, at the fifth connection terminal B5, the third transistor Q3 is passing so that the second connection point P2 is connected to ground 9 via the seventh resistor R7. The fourth transistor Q4 is then in the blocking state equivalent to an open switch between the second B2 and the third B3 connection terminals and when no voltage is applied at the fifth connection terminal B5, the third transistor Q3 is in a blocking state so that a voltage is applied at the connection point P2 which makes the fourth transistor passing so that the third connection terminal B3 is connected to the second connection terminal via the resistors R8 and R9 .

Moreover, the diode D makes it possible to avoid recirculation of the fourth transistor Q4 when the second transistor Q2 is conducting. The diode is located at the second switching element 5b because it is the one that is connected to the power source delivering the lowest voltage. The diode D can also be placed in series with the resistor R8 however this adds a residual threshold voltage to the signal supplied to the third connection terminal B3. The values of the fourth R4 and the ninth R9 resistors can vary between 0 and 100 1 <Ω, These resistors are optional. Furthermore, the values of the other resistors can vary depending on the desired voltages, especially at the third connection terminal B3.

Thus, the application or not, by the control device 7, a voltage at the fourth B4 and the fifth B5 connection terminals is used to supply the power supply input of a control unit electronics 3 connected to the third connection terminal B3, either by a first power source connected to the first connection terminal B1, or to a second power source connected to the second power supply terminal B2. In the case of an application for a motor vehicle, the control unit 3 may be configured to supply a first type of sensor requiring a first supply voltage or a second type of sensor requiring a second supply voltage, the electrical supply circuit 1 described above then allows to connect the control unit 3 to the power source delivering the supply voltage appropriate to the type of sensor. For this a control device 7 comprising a first control output connected to the fourth connection terminal B4 and a second control output connected to the fifth connection terminal B5 make it possible to select the supply voltage of the control unit 3 Thus, only one model of control unit 3 can be used for several types of sensors, for example for sensors requiring a 13 V operating voltage or sensors requiring a supply voltage of 5 V, which makes it possible to to reduce the number of control unit references 3 necessary for all the vehicles of a manufacturer or an automotive supplier.

Furthermore, it should be noted that the invention may extend to a number of power sources greater than two. In this case, each power source is connected to a similar switching element to the second switching element 5B. Only the switching element connected to the supply source delivering the highest voltage could not include a diode.

Claims (10)

1. Electrical supply circuit (1) of an electronic control unit (3), said circuit (1) comprising: - a first connection terminal (B1) intended to be connected to a first power source associated with a first voltage level, - a second connection terminal (B2) intended to be connected to a second power source associated with a second voltage level different from the first voltage level, - a third connection terminal (B3) for to be connected to the electronic control unit (3), - a first switching element (5a) arranged to turn on the first (B1) and the third (B3) connection terminal or to interrupt the conduction between the first (B1) and Bl) and the third (B3) connection terminal, - a second switching element (5b) arranged to turn on the second (B2) and the third (B3) connection terminal or to interrupt the conduction between the second (B2) and the tr eighth (B3) connection terminal, - a control device (7) configured to control the conduction or out of conduction of the first (5a) and second (5b) switching element according to the configuration of the unit of electronic control (3). 2. Power supply circuit (1) according to claim 1, wherein said control unit (3) is configured to supply a first type of sensor requiring a first supply voltage or a second type of sensor requiring a second voltage. power. 3. Power supply circuit (1) according to claims 1 or 2, wherein the control device (7) comprises a microcontroller. 4. Power supply circuit (1) according to one of the preceding claims, wherein the first voltage level is a voltage of 5V DC and the second voltage level corresponds to a voltage delivered by a battery, in particular 13 V. Power supply circuit (1) according to one of the preceding claims, wherein the first (5a) and the second (5b) switching elements comprise at least one transistor (Q2, Q4) and a bias resistor ( R3, R8) of the transistor (Q2, Q4). 6. Power supply circuit (1) according to claim 5, wherein the first switching element (5a) comprises: a first NPN transistor (Ql) whose base is connected via a first resistor (RI) at a fourth connection terminal (B4) intended to be connected to the control device, the emitter is connected to ground (9) and the collector is connected to a first connection point (PI) via a second resistor (R2) a second PNP transistor (Q2) whose base is connected to the first connection point (PI), the collector is connected to the third control terminal (B3) via a third resistor (R3) and the transmitter is connected to the first connection terminal (B1), the first connection point (P1) being connected to the first connection terminal (B1) via a fifth resistor (R5), and the second switching element (5b) comprising: a third NPN transistor (Q3) whose base is connected via a sixth resistor (R6) at a fifth connection terminal (B5) to be connected to the control device (7), the emitter is connected to ground (9) and the collector is connected to a second connection point ( P2) via a seventh resistor (R7), - a fourth PNP transistor (Q4) whose base is connected to the second connection point (P2), the collector is connected to the third control terminal (B3) via an eighth resistor (R8) and the emitter is connected to the second connection terminal (B2), the second connection terminal (B2) being connected to the second connection point (P2) via a tenth resistor (RIO) and a diode (D). ). The power supply circuit (1) according to claim 6, wherein the emitter of the second PNP transistor (Q2) is connected to the first connection terminal (B1) via a fourth resistor (R4) and / or the transmitter of the fourth PNP transistor (Q4) is connected to the second connection terminal (B2) via a ninth resistor (R9). 8. Power supply circuit according to claim 7, wherein the values of the fourth resistor (R4) and the tenth resistor (RIO) are between 0 and 100 ΚΩ. 9. Power supply circuit according to one of the preceding claims, wherein the third control terminal (B3) is connected to ground (9) via a capacitor (C). Electrical supply circuit according to one of claims 6 to 9, wherein the control device (7) comprises a first control output connected to the fourth connection terminal (B4) and a second control output connected to the fifth connection terminal (B5).