Device and method for powering electronic circuits

Abstract

The present invention relates to an apparatus and method for powering an electronic circuit. The apparatus is configured to: cause a first current to flow through a first conductor connected to a node, the first current being a mirror image of a second current consumed by the electronic circuit; cause a third current to flow through a second conductor connected to the node, the first branch of the current mirror conducting the third current; cause a fourth constant current to flow through a third conductor connected to the node; consume a fifth current, the fifth current being a mirror image of the third current; and adjust the potential of the node by acting on the gate potential of a transistor in electrical series with the second branch of the current mirror.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims the benefit of French Patent Application No. 2008675, filed on August 25, 2020, which is incorporated herein by reference. Technical Field

[0003] The present disclosure relates generally to electronic devices and methods, and more particularly, to electronic circuit powering devices and methods. Background Art

[0004] The electronic circuit may be integrated in an electronic chip. The chip usually includes an electronic circuit power supply having the function of delivering a voltage from the supply voltage of the chip to the electronic circuit. The electronic circuit consumes a variable current depending on its operation. The voltage delivered to the circuit is usually stabilized or regulated so as to maintain a constant value during variations in the current consumed by the circuit.

[0005] Electronic circuits can contain confidential data that is protected from any access by unauthorized persons. This occurs, for example, when the chip is intended to receive, store and / or communicate passwords or encrypted data (e.g. keys). An attacker may then attempt to obtain all or part of the confidential data.

[0006] In one type of attack, the attacker manipulates the chip and attempts to measure the current supplied to the electronic circuit power supply in order to extract information about the operation of the electronic circuit based on changes in the current, thereby being able to infer confidential information. Summary of the invention

[0007] There is a need for a power supply device and method for electronic circuits containing confidential data, which can protect the confidential data from attacks.

[0008] There is a need to simplify existing electronic circuit powering apparatus and methods.

[0009] One embodiment overcomes all or part of the disadvantages of known electronic circuit power supplies.

[0010] One embodiment overcomes all or part of the disadvantages of known methods of powering electronic circuits.

[0011] According to a first aspect, an embodiment provides a device for powering an electronic circuit, the device being configured to cause a first current to flow through a first conductor connected to a node, the first current being a mirror image of a second current consumed by the electronic circuit; cause a third current to flow through a second conductor connected to the node, a first branch of the current mirror conducting the third current; cause a fourth constant current to flow through a third conductor connected to the node; consume a fifth current, the fifth current being a mirror image of the third current; and adjust the potential of the node by acting on the gate potential of a transistor electrically connected in series with the second branch of the current mirror.

[0012] One embodiment provides a method for powering an electronic circuit, comprising the steps of: causing a first current to flow through a first conductor connected to a node, the first current being a mirror image of a second current consumed by the electronic circuit; causing a third current to flow through a second conductor connected to the node, the first branch of the current mirror conducting the third current; causing a fourth constant current to flow through the third conductor connected to the node; consuming a fifth current that is a mirror image of the third current; and adjusting the potential of the node by acting on the gate potential of a transistor electrically connected in series with the second branch of the current mirror.

[0013] According to one embodiment, the transistor couples a node to which a potential is applied (preferably fixed) to the gates of the transistors of the current mirror coupled together.

[0014] According to one embodiment, the transistor is smaller than the transistor of the second branch of the current mirror.

[0015] According to one embodiment, the potential of the node is adjusted to a constant value.

[0016] According to one embodiment, the resistive element conducts a fourth current.

[0017] According to one embodiment, the constant value is the value of a regulated potential for powering the electronic circuit.

[0018] According to one embodiment, a first branch of the further current mirror conducts the first current; the potential of the node is adjusted to the value of the potential of a terminal of a second branch of the further current mirror.

[0019] According to one embodiment, the operational amplifier receives the potential difference between the node and a terminal of the second branch of the further current mirror and acts on the gate potential of the transistor.

[0020] According to one embodiment, the second branch of the further current mirror is electrically connected in series with the electronic circuit between a terminal to which a supply voltage is applied, referenced to a reference potential, and a terminal to which the reference potential is applied.

[0021] According to one embodiment, the fifth current is provided by a terminal to which a supply voltage is applied.

[0022] According to one embodiment, a terminal of the second branch of the current mirror has a potential adjusted to the potential value of the node.

[0023] According to one embodiment, an additional transistor is connected in series with the second branch of the current mirror; the additional transistor is controlled by the output of an operational amplifier receiving the difference between the potential of the node and the potential of the terminal of the second branch of the current mirror.

[0024] According to one embodiment, a ratio between the values ​​of the fifth current and the third current is equal to another ratio between the values ​​of the second current and the first current, or is equal to a sum of another ratio and unity (unity, 1).

[0025] One embodiment provides an electronic circuit comprising an apparatus such as defined above and the electronic circuit, or configured to implement a method such as defined above.

[0026] According to a second aspect, an embodiment provides an electronic circuit power supply device, configured to cause a first current to flow through a first conductor connected to a node, the first current being a mirror image of a second current consumed by the electronic circuit; cause a third current to flow through a second conductor connected to the node; adjust the potential of the node to a constant value by acting on the third current; cause a fourth constant current to flow through a third conductor connected to the node; and consume a fifth current, which is a mirror image of the third current.

[0027] One embodiment provides a method for powering an electronic circuit, comprising the steps of: causing a first current to flow through a first conductor connected to a node, the first current being a mirror image of a second current consumed by the electronic circuit; causing a third current to flow through a second conductor connected to the node; adjusting the potential of the node to a constant value by acting on the third current; causing a fourth constant current to flow through a third conductor connected to the node; and consuming a fifth current, the fifth current being a mirror image of the third current.

[0028] According to one embodiment, the resistive element conducts a fourth current.

[0029] According to one embodiment, the constant value is the value of a regulated potential for powering the electronic circuit.

[0030] According to one embodiment, a first branch of a current mirror coupled to the first conductor conducts the first current; a terminal of a second branch of the current mirror has a potential adjusted to a constant value.

[0031] According to one embodiment, the second branch of the current mirror is electrically connected in series with the electronic circuit between a terminal to which a supply voltage is applied with reference to a reference potential and a terminal to which the reference potential is applied.

[0032] According to one embodiment, the fifth current is provided by a terminal to which a supply voltage is applied.

[0033] According to one embodiment, a first branch of a current mirror coupled to the second conductor conducts a third current; a second branch of the current mirror coupled to the second conductor consumes a fifth current; and the potential of the node is adjusted by acting on the potential of gates coupled together of transistors of the current mirror coupled to the second conductor.

[0034] According to one embodiment, the potential applied to the gate is implemented by an operational amplifier receiving the potential difference between the node and a terminal of the second branch of the current mirror coupled to the first conductor.

[0035] According to one embodiment, the action on the potential of the gate is obtained by acting on a control potential of another transistor electrically in series with the second branch of the current mirror coupled to the second conductor; and preferably the other transistor couples the gate to another node to which the supply potential is applied.

[0036] According to one embodiment, the further transistor is smaller than the transistor of the second branch of the current mirror coupled to the second conductor.

[0037] According to one embodiment, a terminal of the second branch of the current mirror coupled to the second conductor has a potential adjusted to a constant value.

[0038] According to one embodiment, an additional transistor is connected in series with the second branch of the current mirror coupled to the second conductor; the additional transistor is controlled by the output of an operational amplifier, which is configured to amplify the difference between the constant value and the potential of the terminal of the second branch of the current mirror coupled to the second conductor.

[0039] According to one embodiment, a ratio between the values ​​of the fifth current and the third current is equal to another ratio between the values ​​of the second current and the first current, or is equal to a sum of another ratio and 1.

[0040] One embodiment provides an electronic chip comprising an apparatus and an electronic circuit such as defined herein, or configured to implement a method such as defined herein. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] The above features and advantages and others will be described in detail in the following description of specific embodiments given by way of illustration and not limitation with reference to the accompanying drawings, in which:

[0042] Figure 1 An example of an electronic circuit power supply device of the type to which the described embodiments apply is schematically shown;

[0043] Figure 2 An embodiment of an electronic circuit power supply device according to the first aspect is schematically shown;

[0044] Figure 3schematically shows an embodiment of an electronic circuit power supply device according to the second aspect; and

[0045] Figure 4 An embodiment of an electronic circuit power supply device combining the first aspect and the second aspect is schematically shown. DETAILED DESCRIPTION

[0046] In different figures, the same features have been designated by the same references. In particular, common structural and / or functional features in various embodiments may have the same references and may be provided with the same structure, dimensions and material properties.

[0047] For the sake of clarity, only the steps and elements useful for understanding the embodiments described herein are described in detail. In particular, electronic circuits powered by a supply voltage are not described in detail, the described embodiments being compatible with common electronic chip circuits.

[0048] Unless otherwise specified, when referring to two elements being connected together, it means a direct connection without any intermediate elements except conductors, and when referring to two elements being coupled together, it means the two elements may be connected or they may be coupled via one or more other elements.

[0049] In the following disclosure, unless otherwise stated, when referring to absolute position qualifiers, such as terms "front", "back", "up", "down", "left", "right", etc., or relative position qualifiers, such as terms "above", "below", "higher", "lower", etc., or orientation qualifiers, such as "horizontal", "vertical", etc., reference is made to the orientation shown in the figure.

[0050] Unless otherwise indicated, "about," "approximately," "substantially," and "on the order of" mean within 10%, preferably within 5%.

[0051] The described embodiments include transistors of the so-called metal-oxide-semiconductor (MOS) type. Although the term MOS type was originally used to refer to transistors with a metal gate and an oxide gate insulator, due to the development of this type of transistor, the MOS type is now understood to include field effect transistors with a gate made of any electrical conductor and a gate insulator made of any dielectric or electrical insulator.

[0052] Figure 1 An example of a power supply device 100 for an electronic circuit 110 (circuit) of the type to which the described embodiments are applicable is schematically shown.

[0053] The power supply device 100 and the electronic circuit 110 are usually included in an electronic chip. The electronic chip can be formed by a package (preferably compact) and one or more wafer parts (preferably semiconductors), the wafer part having the device 100 and the circuit 110 formed inside and on top thereof. The package includes connection areas or connection pins with other electronic circuits outside the circuit, such as connections with a printed circuit board PCB. The electronic circuit can also be formed by a wafer part, which is preferably a semiconductor, having the device 100 and the circuit 110 located inside and on top thereof.

[0054] The circuit 110 may be any type of electronic chip circuit. The circuit 110 may include a plurality of sub-circuits powered in parallel by the device 100. The electronic chip may also include other electronic circuits in addition to the circuit 110.

[0055] The device 100 comprises a component 120 which is electrically connected in series with the electronic circuit 110 between a terminal or node 130 to which a supply voltage VCC is applied with reference to a reference potential GND (eg ground) and a terminal or node 132 to which a reference potential GND is applied.

[0056] The expression terminal that applies a voltage with reference to a reference potential means that the voltage is equal to the difference between the potential applied to the terminal and the reference potential. In other words, the voltage VCC corresponds to the potential applied to the terminal 130. The voltage VCC may be a voltage transmitted to the electronic chip for its operation.

[0057] Typically, component 120 is located on the side of terminal 130 to which voltage VCC is applied relative to circuit 110. For example, component 120 is connected or coupled to terminal 130. Furthermore, component 120 may be coupled, preferably connected to terminal 132 to which reference potential GND is applied.

[0058] The component 120 delivers a voltage VDD referenced to the reference potential GND to the circuit 110 at a node 134 of the connection between the component 120 and the circuit 110. In other words, the voltage VDD referenced to the reference potential GND, or the potential VDD, is applied to the node 134.

[0059] In the example shown, the voltages VCC and VDD are positive. The chip supply voltage VCC is typically in the range of 3.3V to 5V, while the voltage VDD delivered by the component 120 is typically in the order of 1.2V.

[0060] Component 120 may include, for example, a P-channel MOS transistor T121, coupling nodes 130 and 134. More specifically, transistor T121 has its conductive terminals coupled, preferably connected to respective nodes 130 and 134. The expression conductive terminals of a transistor refers to terminals of the transistor that are electrically connected together in a conductive state and electrically insulated from each other in a non-conductive state. In the example shown, transistor T121 has a source terminal (S) coupled (preferably connected) to node 130, and a drain terminal (D) coupled (preferably connected) to node 134.

[0061] The component 120 may include an operational amplifier 122 that controls the transistor T121. In other words, in an example where the transistor T121 is of MOS type, the transistor T121 has a gate coupled to, preferably connected to, the output of the operational amplifier 122. The operational amplifier 122 thus receives the difference between the voltage VDD transmitted to the electronic circuit 110 and the potential VDD0 having a constant value (i.e., constant relative to the potential GND). More specifically, the non-inverting input (+) of the operational amplifier 122 may be coupled, preferably connected to the node 134, and the inverting input (-) of the operational amplifier 122 may be coupled, preferably connected to a node to which the constant potential VDD0 is applied. The element that transmits the potential VDD0 from the voltage VCC is neither described nor shown, and the embodiment is compatible with such a common element.

[0062] In operation, the operational amplifier 122 and the transistor T121 regulate (i.e., stabilize) the voltage VDD delivered to the circuit 110 to a value equal to the constant value of the potential VDD0. In other words, the operational amplifier 122 acts on the control of the transistor T121 to keep the voltage VDD delivered to the circuit 110 at the constant value of the potential VDD0. The component 120 may include a transistor T123, which forms a current mirror 124 with the transistor T121.

[0063] The so-called “size ratio between transistors” refers to the ratio of the width (W) and length (L) of the gate of one transistor relative to the ratio of the width and length of the gate of another transistor.

[0064] A current mirror means a circuit comprising two branches provided so that the current in one of the two branches is a mirror image of the current in the other branch. Being mirror images of each other means that the values ​​of the currents have a constant ratio. Preferably, the current mirror comprises, more preferably is formed by, two MOS transistors having channels of the same conductivity type receiving the same control voltage. In MOS type transistors, the control voltage refers to the voltage applied between the gate and the source of the transistor. The transistors of the current mirror are provided, as is usual in a current mirror, so that when the drain potentials of the transistors are equal, the current flowing through the transistors is at a constant ratio equal to the size ratio of the transistors. Preferably, in the current mirror, the gates of the two transistors are coupled together, more preferably connected together, and their sources are coupled together, more preferably connected together. Preferably, in the current mirror, each transistor defines a branch of the current mirror. As a variant, the branches may include corresponding resistors having a predetermined value ratio.

[0065] The component 120 may include, for example, a P-channel MOS transistor T125. For example, the source of the transistor T125 is coupled, preferably connected to the drain of the transistor T123. The transistor T125 is controlled by an operational amplifier 126. The operational amplifier 126 receives the potential difference between the drain terminals of the transistors T121 and T123 of the current mirror 124. More specifically, the operational amplifier 126 receives the drain potential of the transistor T123 at the inverting input (-) and the drain potential of the transistor T121 at the non-inverting input (+).

[0066] In operation, the device consumes a current I0 provided by the node VCC. The amplifier 126 and the transistor T125 adjust the drain potential of the transistor T123 so that the drain potential of the transistor T123 is equal to the drain potential of the transistor T121. This makes it possible to obtain a current I1 in the transistor T123, the value of which is in a constant ratio with the current I2 consumed by the electronic circuit 110. In other words, the current I1 is a mirror image of the current I2. The currents I1 and I2 verify the equation I1=I2 / K124, where K124 represents a constant, and for simplicity, the currents and their values ​​are specified in the same way. Due to the fact that the current I0 is the sum of the currents I1 and I2, the currents I0 and I1 verify the equation I1=I0 / (K124+1), in other words, the current I1 is also a mirror image of the current I0. For example, the constant K124 is in the range of 5 to 200, preferably equal to 100.

[0067] Component 120 may further include a transistor T127, such as an N-channel MOS transistor. Transistor T127 has a drain terminal 128, which is preferably connected or coupled to the drain of transistor T123 through transistor T125. The source of transistor T127 is coupled, preferably connected to terminal 132 to which reference potential GND is applied. In other words, transistors T123, T127 and T125 are electrically connected in series between terminals 130 and 132. In particular, transistors T123, T125 and T127 conduct the same current I1. The gate and drain of transistor T127 are coupled together, preferably connected together.

[0068] The device 100 includes a node 150. The node 150 is coupled to a terminal 132 to which a reference potential GND is applied via a transistor t145. The transistor T145 may be an N-channel MOS type. In particular, the transistor T145 has a drain terminal coupled (preferably connected) to the node 150 and a source terminal coupled (preferably connected) to the terminal 132.

[0069] N-channel transistors T127 and T145 form a current mirror 146. Drain terminal 128 and node 150 form the terminals of the respective branches of the current mirror.

[0070] In operation, the branch of the current mirror 146 formed by the transistor T145 conducts a current I1 ′ originating from the node 150 .

[0071] The device 100 further includes a current source 155, which couples the terminal 130 to which the voltage VCC is applied to the node 150. The current source delivers a constant current I4 to the node 150.

[0072] The device 100 comprises a transistor T160 coupling the node 150 to the terminal 132 to which a reference potential is applied. The transistor T160 may be of N-channel MOS type, the drain of which is coupled, preferably connected, to the node 150, and the source of which is coupled, preferably connected, to the terminal 132.

[0073] The device 100 further comprises a component 170 for controlling the transistor T160. The component 170 couples the terminal 130 to which the voltage VCC is applied and the terminal 132 to which the reference potential GND is applied. The component 170 receives the difference between the potential of the node 150 of the transistor T127 and the potential of the drain terminal 128. In other words, the component 170 receives the difference between the potentials of the terminals of the branches of the current mirror 146.

[0074] The assembly 170 comprises a transistor T172, which forms a current mirror 174 with the transistor T160. The transistor T172 may be of N-channel MOS type. The transistor T172 may have its source coupled, preferably connected to the terminal 132 to which the reference potential GND is applied. The drain of the transistor T172 may preferably be connected or coupled to the terminal 130 to which the potential VCC is applied, via a transistor T175. The transistor T175 is then connected in series between the terminals 130 and 132 with the branch of the current mirror 174 formed by the transistor T172.

[0075] Preferably, the component 170 includes an operational amplifier 176 that controls the transistor T175. The operational amplifier 176 receives the difference between the potentials of the drains of the transistors of the current mirror 174, in other words, the operational amplifier 176 is configured to amplify the difference. For example, the transistor T175 is of a P-channel MOS type, and the operational amplifier 176 has an inverting input (-) coupled (preferably connected) to the node 150, and a non-inverting input (+) coupled (preferably connected) to a node 177 where the drains of the transistors T172 and T175 are connected to each other. The node 177 defines the terminal of the branch of the current mirror 174 formed by the transistor T172.

[0076] In operation, transistor T160 causes current I3 to flow from node 150, in other words, transistor T160 conducts current I3. Amplifier 176 and transistor T175 adjust the potential of terminal 177 to the value of the potential of node 150. Therefore, transistor T172 conducts current I5, which is a mirror image of current I3 and is provided by terminal 130 to which potential VCC is applied.

[0077] The device 100 also includes an operational amplifier 178. The operational amplifier 178 receives the potential difference between the node 150 and the drain 128 of the transistor T127. More specifically, the operational amplifier 178 has an inverting input (-) coupled (preferably connected) to the drain terminal 128, and a non-inverting input (+) coupled (preferably connected) to the node 150. The operational amplifier 178 acts on the potential of the gates of the transistors T160 and T172 of the current mirror 174, which are coupled together. In other words, the output of the operational amplifier 178 is coupled, preferably connected, to the gates of the transistors T160 and T172.

[0078] In operation, the operational amplifier 178 adjusts the potential of the node 150 to a value equal to the potential of the drain terminal 128 by acting on the current I3. Therefore, the current I1' is a mirror image of the current I1 by the current mirror 146. Due to the fact that the current I1 is a mirror image of the currents I2 and I0, the current I1' is a mirror image of the currents I0 and I2 and has a ratio of 1 / K with the current I0. In other words, the current I1' verifies the relationship I1'=I0 / K. As an example, the current mirror 146 has a current ratio equal to 1. The ratio 1 / K can be equal to 1 / (K124+1), for example, equal to 1 / 101.

[0079] Preferably, transistors T160 and T172 are arranged so that current I5 has a ratio K with current I3, which is the inverse of the ratio 1 / K between current I1' and current I0. In other words, the ratio K between the values ​​of current I5 and I3 is equal to the sum of unity 1 and the ratio K124 between the value of current I2 consumed by circuit 110 and I1' in transistor T145. Therefore, regardless of the variation of current I2 consumed by electronic circuit 110, the sum I0+I4+I5 of currents I0, I4 and I5 provided by terminal 130 remains constant, equal to the value (K+1)*I4.

[0080] Therefore, an attacker searching for variations in the current I0+I5 consumed by the electronic chip in order to infer therefrom confidential data present in the electronic circuit 110 will not discover the variations and therefore cannot carry out the attack. The electronic circuit is thus protected from such attacks.

[0081] According to a first aspect, an embodiment of an electronic circuit power supply device and method for protecting an electronic circuit from the above-mentioned attack, with Figure 1 Compared to the example of the device 100, an improvement in protection against attacks and / or a faster variation of the current I2 supplied to the electronic circuit and / or a reduction in residual variation of the voltage VDD delivered to the circuit is provided.

[0082] According to the second aspect, Figure 1 Compared to the example of the device 100 , embodiments of the electronic circuit powering device and method for protecting the electronic circuit from the above-mentioned attacks provide easier implementation and / or a reduced number of components.

[0083] Figure 2 The embodiment of the device 200 for supplying power to the electronic circuit 110 outside the device according to the first aspect is schematically shown. The circuit 110 is a combination of the above Figure 1 The device 200 and the circuit 110 are preferably comprised in an electronic chip.

[0084] In the example shown, the apparatus 200 includes Figure 1The same or similar elements of the device 100 are arranged in the same or similar manner. These elements and their layout will not be described in detail below. Only the differences are highlighted.

[0085] Device 200 and Figure 1 The difference between the apparatus 100 is that in the apparatus 200, Figure 1 Component 170 of the device 100 is replaced by component 270. Figure 1 Similar to the component 170 of the device 100, the component 270 has a function of controlling the transistor T160 by acting on the current I3 to adjust the potential of the node 150, and has a function of consuming the current I5 which is a mirror image of the current I3. Figure 1 In the same manner as the device 100, the current I5 consumed by the component 270 is added to the current I0 consumed by the electronic circuit 110 and the component 120, so that the total current consumed by the device 200 and the circuit 110 remains constant during operation of the circuit 110. The device 200 thus protects the circuit 110 from attack.

[0086] The component 270 of the device 200 and Figure 1 The component 170 of the device 100 differs in that the component 270 comprises a transistor T210 electrically connected in series with a branch of the current mirror 174 defined by the transistor T172; Figure 1 The operational amplifier 178 of the component 170 is replaced by an operational amplifier 278. The operational amplifier 278 receives the potential difference between the drain terminal 128 and the node 150 and controls the transistor T210; and the conductive terminal of the transistor T210 located on the side of the transistor T175 is coupled, preferably connected to the gates of the transistors T172 and T160 of the current mirror 174. In other words, the transistor T210 couples the gates of the transistors T172 and T160 to the node 130 to which the potential VCC is applied. The potential VCC is preferably fixed, that is, constant relative to the potential GND.

[0087] In the example shown, transistor T210 is a P-channel MOS type. In this example, the source of transistor T210 is coupled, preferably connected to node 130 to which power supply potential VCC is applied. In this example, amplifier 278 has a non-inverting input (+) coupled (preferably connected) to terminal 128, an inverting input (-) coupled (preferably connected) to node 150, and an output coupled (preferably connected) to the gate of transistor T210.

[0088] Preferably, the transistor T175 couples the drains of the transistors T210 and T172 together. In other words, the transistor T175 is connected in series with the transistors T210 and T172 and is located between the transistors T210 and T172.

[0089] In operation, amplifier 278 acts on the gate potential of transistor T210. Since transistor T210 couples the gates of transistors T172 and T160 to node 130 to which potential VCC is applied, this results in an action on the potential of the gates of transistors T172 and T160 of current mirror 174, which are coupled together. This acts on current I3 to adjust the potential of node 150 to the value of the potential of drain terminal 128 of transistor T127. Transistor T160 is thus controlled to adjust the potential of node 150 by acting on current I3.

[0090] and Figure 1 Compared to the device 100, the output of the amplifier 278 thus controls the gate of the transistor T172 via the transistor T210. As described above, the transistor T172 generally has a size greater than the transistor T160, in other words, the transistor T160 is smaller than the transistor T172. For example, the size ratio of the transistors T172 and T160 is in the range of about 50 to about 200, and is preferably equal to 101. In particular, the transistor T210 is smaller than the transistor T175.

[0091] Therefore, transistor T172 has a relatively high stray gate capacitance compared to transistor T210. Due to the fact that the output of amplifier 278 controls transistor T172 via transistor T210, the control of transistor T172 by amplifier 278 is relatively high. Figure 1 The amplifier 178 of the device 100 controls the transistor T172 quickly.

[0092] Therefore, with Figure 1 Compared with the device 100 of FIG. 1 , the current I5 consumed by the device 200 follows the change of the current I2 consumed by the circuit 110 more quickly.

[0093] Due to the fact that transistor T210 is connected in series with transistor T172, during the change of current I2, a difference between the potential of node 150 and the potential of the drain of transistor T172 is instantaneously caused, and amplifier 278 and transistor T210 act on the drain potential of transistor T172 to compare with the potential of the drain of transistor T172 in the case of a change in current I2. Figure 1 The difference is compensated more quickly in the circuit of the component 170 of the device. In the example shown, if the potential of the node 150 increases momentarily, the transistor T210 becomes more conductive, which helps to increase the drain potential of the transistor T172. In the example shown, if the potential of the node 150 decreases momentarily, the transistor T210 becomes less conductive, which helps to reduce the drain potential of the transistor T172. This helps to make the change of the current I2 (followed by the current I5) faster than in the power supply device, in which the potential of the gates of the transistors T160 and T172 will be controlled by a transistor that is not connected in series with the transistor T172.

[0094] The fact that the current I5 follows the variation of the current I2 more quickly reduces the duration and the amplitude of the transient residual variation of the current consumed by the chip when the current I2 changes value. This makes it possible, for the same rapidity of the variation of the value of the current I2, to reduce the risk of an attacker transiently detecting such residual variation of the current consumed by the chip. The protection against attacks is thus improved. This also makes it possible, for a given level of protection, i.e. a given level of residual variation of the current consumed by the chip, to vary the current I2 consumed by the electronic circuit 110 more quickly. The electronic circuit 110 can thus be faster and / or, by increasing the rapidity of the operational amplifier 122, a more stable voltage VDD can be provided to the circuit 110.

[0095] Embodiments according to the first aspect are not limited to the specific above examples. In the device 200, the component 120 may be replaced by any circuit configured to control the transistor T145; and transmit a value of the potential of the node 150 for which the current I1' in the transistor T145 is a mirror image of the current I2 consumed by the circuit 110.

[0096] Specifically, instead of transistor T145 coupling node 150 to terminal 132 to which a reference potential is applied, a transistor coupling node 150 to terminal 130 to which voltage VCC is applied may be provided, as described below in conjunction with Figure 4 The current Ii1 ′ flowing through the conductor 251 connected to the node 150 is replaced by a current flowing through the conductor connected to the node 150 toward the node 150 .

[0097] Thus, component 120 and transistor T145 may be replaced by any circuit configured to cause a current to flow through a conductor connected to node 150 and to deliver a potential value of node 150 for which the current is a mirror image of current I2 consumed by circuit 110 .

[0098] Figure 3 The embodiment of the power supply device 300 for the electronic circuit 110 outside the device 300 according to the second aspect is schematically shown. The circuit 110 is the above combined Figure 1 The device 300 and the circuit 110 are preferably included in an electronic chip. The device 300 includes Figure 1 For elements that are the same or similar to the device 100, these elements will not be described in detail.

[0099] The device 300 comprises a component 320 electrically connected in series with the electronic circuit 110 between the terminal 130 to which the voltage VCC is applied and the terminal 132 to which the reference potential GND is applied. Preferably, the component 320 is located on the side of the terminal 130 to which the potential VCC is applied relative to the circuit 110. For example, the component 320 is connected to the terminal 130. Furthermore, the component 320 may be coupled, preferably connected to the terminal 132 to which the reference potential GND is applied. The component 320 transmits the voltage VDD to the circuit 110 at the node 134 defined by the drain terminal of the transistor T121.

[0100] Component 320 includes transistor T121 and operational amplifier 122. Figure 1 The transistor T121 and the operational amplifier 122 of the device 100 are the same or similar, and are arranged the same or similar. Figure 1 In the same manner as the device 100 , the operational amplifier 122 and the transistor T121 regulate the voltage VDD transmitted to the circuit 110 .

[0101] The device 300 includes a node 150 coupled to a terminal 130 to which a voltage VCC is applied via a transistor T345. The transistor T345 may be of a P-channel MOS type. In particular, the transistor T345 has a drain terminal coupled (preferably connected) to the node 150 and a source terminal coupled (preferably connected) to the terminal 130.

[0102] The P-channel transistors T121 and T345 form a current mirror 346. The drain terminal 134 of the transistor T121 and the node 150 form the terminals of the respective branches of the current mirror 346. Preferably, the sources of the transistors T121 and T345 are coupled together, more preferably connected together, and the gates of the transistors T121 and T345 are coupled together, more preferably connected together. The branches of the current mirror 346 formed by the transistor T121 are electrically connected in series with the electronic circuit 110 between the terminal 130 to which the reference supply voltage VCC is applied and the terminal 132 to which the reference potential GND is applied.

[0103] In operation, the branch of the current mirror 346 formed by the transistor T345 causes a current I1 ′ to flow toward the node 150 via a conductor 351 connected to the node 150 and coupled to the current mirror 346 .

[0104] The device 300 further includes a resistive element 355 coupling the node 150 to the terminal 132 to which the reference potential GND is applied. The resistive element 355 samples the current I4 from the node 150. In other words, the resistive element 355 causes the current I4 to flow through the conductor 352 connected to the node 150. The resistive element 355 may be formed by a resistor or a plurality of resistors connected in series and / or in parallel.

[0105] The device 300 comprises a transistor T360 coupling the node 150 to the terminal 130 to which the voltage VCC is applied. The transistor T360 may be of p-channel MOS type, the drain of which is coupled, preferably connected, to the node 150, and the source of which is coupled, preferably connected, to the terminal 130.

[0106] The device 300 further comprises a component 370. The component 370 couples the terminal 130 to which the voltage VCC is applied and the terminal 132 to which the reference voltage GND is applied. The component 370 receives the difference between the potentials of the terminals of the branches of the current mirror 146 (formed by the nodes 150 and 134).

[0107] Component 370 includes transistor T372, which forms a current mirror 374 with transistor T360. Transistor T372 can be of P-channel MOS type. Transistor T372 can have its source coupled, preferably connected to terminal 130 to which voltage VCC is applied. The drain of transistor T372 can be preferably connected or coupled to terminal 132 to which reference potential is applied through transistor T375. Then, transistor T375 is connected in series with transistor T372 of current mirror 374 between terminals 130 and 132.

[0108] Preferably, the component 370 comprises an operational amplifier 376 that controls the transistor T375 and receives the difference between the drain potentials of the transistors of the current mirror 374. For example, the transistor is of the N-channel MOS type, and the operational amplifier 376 has an inverting input (-) coupled (preferably connected) to the node 150, and a non-inverting input (+) coupled (preferably connected) to a node 377 connected to each other in the drains of the transistors T372 and T375. The node 377 forms a terminal of the branch of the current mirror 374 defined by the transistor T372.

[0109] In other words, the current mirror 374, transistor T375 and amplifier 376 of the device 300 correspond to Figure 1 The current mirror 174, transistor T175 and amplifier 176 of the device 100, wherein the voltage signs have been swapped, the N and P types of the channels of the transistors have been swapped, and the terminals 130 and 132 have been swapped.

[0110] Therefore, the operation is similar to Figure 1 The transistor T360 causes the current I3 to flow to the node 150 via the conductor 353 connected to the node 150 and coupled to the current mirror 374. The amplifier 376 and the transistor T375 adjust the potential of the terminal 377 to the value of the potential of the node 150. The branch of the current mirror 374 formed by the transistor T372 consumes the current I5 provided by the terminal 130 to which the potential VCC is applied, which current I5 is a mirror image of the current I3.

[0111] The device 300 also includes an operational amplifier 378. The operational amplifier 378 receives the potential difference between the potential of the node 150 and the constant value VCST. More specifically, the operational amplifier 378 has a non-inverting input (+) coupled, preferably connected to the node 150 and an inverting input (-) receiving the potential having the constant value VCST. The output of the operational amplifier 378 is coupled, preferably connected to the gates of the transistors T360 and T372. Therefore, the operational amplifier 378 acts on the potential of the gates of the transistors T360 and T372 of the current mirror 374, which are coupled together.

[0112] In operation, operational amplifier 378 regulates the potential of node 150 to a constant value VCST by acting on current I3.

[0113] Due to the fact that the potential of the node 150 is adjusted to a constant value, the current I4 is constant. Figure 1 Compared to the device 100 of FIG. 1 , the constant current I4 has been obtained more simply by replacing the current source 155 with a simple resistive element, which is arranged to provide a current that remains constant when the voltage across the current source varies.

[0114] According to one embodiment, the constant value VCST is a constant value VCST of the regulated voltage VDD. In the example shown, the non-inverting input of the amplifier 378 is coupled, preferably connected to the node 134 to which the voltage VDD is applied. In another example not shown, the non-inverting input of the amplifier 378 is coupled or connected to a node having a potential of the same value as the voltage VDD, such as the potential VDD0, which node is, for example, the non-inverting input of the amplifier 122.

[0115] Due to the fact that the constant value VCST (so that the potential on the node 150 is regulated) is equal to the value of the voltage VDD, the current I1 flowing through the conductor 351 by the current mirror 346 is a mirror image of the current I2 consumed by the electronic circuit 110. Therefore, the current I1 is a mirror image of the current I0' provided by the terminal 132, the current I0' being the sum of the currents I1' and I2. More specifically, the current I1' verifies the relationship I1'=I0' / (K346+1), where K346 is the ratio between the currents I2 and I1'. In other words, the current I1 verifies the relationship I1'=I0' / K', where K'=K346+1. The value K' can be in the range of 50 to 200, for example being equal to 101.

[0116] Therefore, current I1′, which is a mirror image of current I0′, has flowed through conductor 351 connected to node 150 without using a current such as Figure 1 100 of the transistors T123, T125 and T127. Figure 1Compared to the device of apparatus 100 , apparatus 300 is simpler to form and includes fewer components.

[0117] Transistors T360 and T372 are arranged so that currents I5 and I3 have a ratio equal to the value of constant K346. In other words, the ratio between currents I5 and I3 is the same as the ratio between currents I2 and I1'. Therefore, current I6 provided by terminal 130, which is the sum of currents I3 and I5, has a ratio K with current I3, which is the reciprocal of the ratio 1 / K of currents I1' and I0'. Therefore, regardless of the variation of current I2 consumed by electronic circuit 110, the sum I0'+I6 of currents I0 and I6 provided by current 130 remains constant, equal to K*I4. Therefore, protection circuit 110 is protected from the above-mentioned attack.

[0118] Embodiments according to the second aspect are not limited to the specific examples described above. In the device 300, the component 370 can be replaced by any circuit configured to control the transistor T360 to adjust the potential of the node 150 to a constant value VCST; and consume a current I5 that is a mirror image of the current I3 flowing through the transistor T360, that is, a flowing current I5 that is a mirror image of the current I3, from one of the terminals 130 and 132 to the other of the terminals 130 and 132.

[0119] Preferably, the circuit replacement component 370 comprises a transistor forming a current mirror with a transistor T360, which forms a branch of the current mirror. The other branch of the current mirror consumes the current I5. In the other branch, the potential of the drain terminal is adjusted to a constant value VCST, so that the two drain terminals of the current mirror have the same potential. Therefore, in a variant, the inverting input of the amplifier 376 is not connected or coupled to the node 150, but is connected or coupled to another node with a potential equal to or adjusted to a constant value VCST, such as the node 134 for providing the voltage VDD and the inverting input of the amplifier 122.

[0120] In addition, the component 320 can be replaced by any circuit configured as follows, that is, configured to control the transistor T345 so that the current I1' flows through the transistor T345, and when the voltage across the transistor T345 has a constant value VCST, the current I1' is a mirror image of the current I2. Preferably, such a circuit replacement component 320 includes a transistor that forms a current mirror with the transistor T345, and the transistor T345 forms a branch of the current mirror. In the other branch of the current mirror, the potential of the drain terminal is adjusted to a constant value VCST, so that the two drain terminals of the current mirror have the same potential.

[0121] In particular, a transistor T345 coupling the node 150 to the terminal 130 to which the reference potential GND is applied may be provided instead of a transistor T145 coupling the node 150 to the terminal 132 to which the potential VCC is applied ( Figure 1 ). In the same manner as transistor T345, transistor T145 causes current to flow through a conductor connected to node 150. Thus, one embodiment includes Figure 1 The components of the device 100 are the same as the components except that the amplifier 178 ( Figure 1 ) receives a constant value VCST at its inverting input; an element capable of adjusting the voltage of the drain terminal 128 of the transistor T127 to a constant value VCST is provided in series with the transistors T127 and T125; and preferably, the current source 155 is formed by a resistance element, which makes it possible to simplify the current source 155.

[0122] Therefore, component 320 and transistor T145 may be replaced by any circuit configured to cause current to flow through a given conductor connected to node 150 when the potential of node 150 has a constant value VCST.

[0123] Furthermore, the resistor element 355 may be replaced with any current source that can obtain a constant current I4 when the voltage across the current source has a constant value VCST. In particular, the resistor element 355 does not need to benefit from the above-mentioned advantage of not using components such as transistors T123, T125, and T127 ( Figure 1 ).

[0124] Figure 4 An embodiment of a device 400 for powering an electronic device 110 in combination with the first aspect and the second aspect is schematically shown. The circuit 110 is a device 400 in combination with the first aspect and the second aspect. Figure 1 The device 400 and the circuit 110 are preferably comprised in an electronic chip.

[0125] In the example shown, the apparatus 400 includes Figure 3 The same or similar elements of the device 300 are arranged in the same or similar manner. These elements and their layout will not be described in detail below. Only the differences are highlighted.

[0126] Device 400 and Figure 3 The difference between the device 300 and the device 400 is that, in the device 400, the component 370 of the device 300 is replaced by the component 470. Similar to the component 370 of the device 300, the component 470 has the function of controlling the transistor T360 to adjust the potential of the node 150 by acting on the current I3, and the function of consuming the current I5 which is the mirror of the current I3. The device 400 thus protects the circuit 110 from attack.

[0127] The component 470 of the device 400 is Figure 3 The component 370 of the device 300 is different in that the component 370 includes a transistor T410 electrically connected in series with a transistor T372; Figure 3 The operational amplifier 378 of the component is replaced by the operational amplifier 478. The operational amplifier 478 receives the difference between the constant value VCST and the potential of the node 150 and controls the transistor T410; and the conductive terminal 412 of the transistor T410 located on the transistor T375 side is coupled, preferably connected to the gates of the transistors T372 and T360 of the current mirror 374.

[0128] In the example shown, transistor T410 is an N-channel MOS type. In this example, the source of transistor T410 is coupled, preferably connected to terminal 132 to which a reference potential GND is applied. In this example, amplifier 478 has a non-inverting input (+) coupled (preferably connected) to node 134 or a node to which a potential equal to or adjusted to a constant value is applied; an inverting input (-) coupled (preferably connected) to node 150; and an output coupled (preferably connected) to the gate of transistor T410. In other words, transistor T410 couples the gates of transistors T372 and T360 to node 132 to which a fixed potential GND is applied.

[0129] In operation, amplifier 478 acts on the gate potential of transistor T410. This results in the action of current I3 in transistor T360 to regulate the potential of node 150 to a constant value VCST. Transistor T360 is thus controlled to regulate the potential of node 150 by acting on current I3.

[0130] and Figure 3 Compared to the device 300 of FIG. 400 , in the device 400 , the output of the amplifier 478 thus controls the gate of the transistor T372 via the transistor T410 . The transistor T410 is smaller than the transistor T372 . Figure 2 In the same manner as in the device 200, the control ratio of the amplifier 478 to the transistor T372 is Figure 3 The control of the transistor T372 by the amplifier 378 of the device 300 is faster.

[0131] With Figure 2 In the same manner as the apparatus 200, in the apparatus 400, Figure 3 Compared to the device 300 of FIG. 4 , the current I5 consumed by the device 400 follows the changes of the current I2 consumed by the circuit 110 more quickly due to the fact that the control of the transistor T372 is faster and due to the fact that the transistor T410 is connected in series with the transistor T372. Figure 3This provides improved protection against attacks and / or faster variation of the current I2 supplied to the electronic circuit and / or a reduction in residual variation of the voltage VDD supplied to the circuit compared to the device 300 of FIG.

[0132] Various embodiments and variations have been described. Those skilled in the art will appreciate that certain features of these embodiments may be combined, and those skilled in the art will readily discover other variations. Specifically, although positive voltages VCC and VDD have been described above, those skilled in the art are capable of adapting the above embodiments to negative voltages VCC and / or VDD, for example, by swapping the N and P channel conductivity types of transistors, by swapping the inverting and non-inverting inputs of operational amplifiers, and by inverting the direction of current.

[0133] In addition, an embodiment in which the transistors are controlled by an operational amplifier is described. Depending on the supply voltage of the amplifier and the characteristics of the amplifier and the transistors, those skilled in the art will be able to implement embodiments that swap the N and P channel conductivity types of one or more transistors, swap the inverting and non-inverting inputs of the associated amplifier.

[0134] Finally, based on the functional indications given above, the practical implementation of the described embodiments and variants is within the capabilities of a person skilled in the art.

Claims

1. A device for powering an electronic circuit, the device comprising: a first transistor having a drain terminal coupled to the node, a first current flowing at the drain terminal of the first transistor; a second transistor having a drain terminal coupled to the electronic circuit, a second current flowing at the drain terminal of the second transistor being a mirror image of the first current, a control terminal of the first transistor being coupled to a control terminal of the second transistor; a third transistor having a drain terminal coupled to the node, a third current flowing at the drain terminal of the third transistor; a resistance element coupled to the node, a fourth constant current flowing through the resistance element; a fourth transistor having a control terminal coupled to the control terminal of the third transistor, a fifth current flowing at a drain terminal of the fourth transistor being a mirror image of the third current; as well as A fifth transistor is configured to adjust the potential of the node by acting on a control terminal of the fifth transistor, wherein the fifth transistor is electrically connected in series with a drain terminal of the fourth transistor. 2 . The apparatus of claim 1 , wherein a source terminal of the fifth transistor is coupled to a reference node, and a drain terminal of the fifth transistor is coupled to a control terminal of the third transistor and a control terminal of the fourth transistor. The device of claim 1 , wherein the fifth transistor is smaller than the fourth transistor. The device according to claim 1 , wherein the potential of the node is adjusted to a constant value. 5 . The apparatus of claim 4 , wherein the constant value is a value of a regulated potential for powering the electronic circuit.

6. The device according to claim 1, wherein: The potential of the node is adjusted to a potential value of a drain terminal of the second transistor.

7. The apparatus of claim 1 , further comprising an operational amplifier configured to: receiving a potential difference between the node and a drain terminal of the second transistor, and Acting on the control terminal of the fifth transistor.

8. The apparatus of claim 1, wherein a source terminal of the second transistor is coupled to a supply voltage, and wherein the electronic circuit is coupled to a reference potential.

9. The apparatus of claim 8, wherein a source terminal of the fifth transistor is coupled to the reference potential.

10. The device of claim 1, wherein a drain terminal of the fourth transistor has a potential adjusted to the potential of the node.

11. The apparatus according to claim 10, further comprising: a sixth transistor having: a drain terminal coupled to the drain terminal of the fourth transistor; a source terminal of the sixth transistor coupled to the drain terminal of the fifth transistor; as well as an operational amplifier coupled to a control terminal of the sixth transistor, the operational amplifier being configured to receive a difference between the potential of the node and the potential of the drain terminal of the fourth transistor. 12 . The device of claim 1 , wherein a first ratio between the values ​​of the fifth current and the third current is equal to a second ratio between the values ​​of the second current and the first current, or equal to a sum of the second ratio and 1.

13. A method of supplying power to an electronic circuit, the method comprising: causing a first current to flow through a drain terminal of a first transistor coupled to the node; causing a second current to flow at a drain terminal of a second transistor coupled to the electronic circuit; The second current is a mirror image of the first current, and the control terminal of the first transistor is coupled to the control terminal of the second transistor; causing a third current to flow through a drain terminal of a third transistor coupled to the node; causing a fourth constant current to flow through a resistive element coupled to the node; causing a fifth current to flow at a drain terminal of a fourth transistor, the fifth current being a mirror image of the third current, the fourth transistor having a control terminal coupled to a control terminal of the third transistor; as well as The potential of the node is adjusted by a fifth transistor by acting on a control terminal of the fifth transistor, and the fifth transistor is electrically connected in series with a drain terminal of the fourth transistor.

14. The method according to claim 13, further comprising: The potential of the node is adjusted to a constant value.

15. The method according to claim 13, further comprising: The potential of the node is adjusted to a potential value of a drain terminal of the second transistor.

16. The method according to claim 15, further comprising: receiving, by an operational amplifier, a potential difference between the node and the drain terminal of the second transistor; as well as The operational amplifier acts on the control terminal of the fifth transistor. 17 . The method of claim 13 , wherein a first ratio between the values ​​of the fifth current and the third current is equal to a second ratio between the values ​​of the second current and the first current, or equal to a sum of the second ratio and 1.

18. An electronic chip, comprising: Electronic circuits; as well as A device configured to supply power to the electronic circuit, the device comprising: a first transistor having a drain terminal coupled to the node, a first current flowing at the drain terminal of the first transistor; a second transistor having a drain terminal coupled to the electronic circuit, a second current flowing at the drain terminal of the second transistor being a mirror image of the first current, a control terminal of the first transistor being coupled to a control terminal of the second transistor; a third transistor having a drain terminal coupled to the node, a third current flowing at the drain terminal of the third transistor; a resistance element coupled to the node, a fourth constant current flowing through the resistance element; a fourth transistor having a control terminal coupled to the control terminal of the third transistor, a fifth current flowing at a drain terminal of the fourth transistor being a mirror image of the third current; and The fifth transistor is configured to adjust the potential of the node by acting on a control terminal of the fifth transistor, the fifth transistor being electrically connected in series with a drain terminal of the fourth transistor.

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