Power supply for an electronic device

Abstract

Powering an Electronic Device This description relates to an electronic device comprising: - a first near-field communication module (34); - at least one second communication module; - at least one portion of volatile memory (381); - at least one register (382); and - at least one first circuit (383) adapted to activate said near-field communication module (34), wherein, when the electronic device (30) is switched on and when the near-field communication device (34) is in standby mode, then the group consisting of said at least one portion of volatile memory (381), said at least one register (382), and said at least one first circuit (383) is powered by a first supply voltage to said at least one second communication module of the device (30). Figure for the abbreviation: Fig. 4

Description

Title of the invention: Power supply for an electronic device Technical field

[0001] The present description relates generally to electronic systems and devices, and the power supply of these systems and devices. The present description relates, more particularly, to electronic devices adapted to near field communication (NFC), and to the adaptation of the power supply means of such electronic devices. Prior art

[0002] Wireless communications are increasingly used nowadays for different applications such as information exchange, banking payments, energy exchanges, etc. There are several types of wireless communication, for example, Near Field Communication (NFC), communications using high frequencies at longer distances such as Bluetooth communications, etc.

[0003] It would be desirable to be able to improve at least in part certain aspects of known devices adapted to near field communication technology. Summary of the invention

[0004] There is a need for devices suitable for near field communication technology that consume less power.

[0005] One embodiment overcomes all or part of the drawbacks of known devices adapted to near-field communication technology.

[0006] One embodiment provides a device adapted to near field communication technology that consumes less power.

[0007] One embodiment provides an electronic device comprising: - a first near-field communication module; - at least one second communication module; - at least part of a volatile memory; - at least one register; and - at least one first circuit adapted to make said near-field communication module active, wherein when the electronic device is turned on and when the near field communication device is in a standby mode, then the group consisting of said at least one part of a volatile memory, said at least one register, and said at least one first circuit is powered by a first supply voltage of said at least one second communication module of the device.

[0008] Another embodiment provides a method of powering an electronic device comprising: - a first near-field communication module; - at least one second communication module; - at least part of a volatile memory; - at least one register; and - at least one first circuit adapted to make said near-field communication module active, wherein when the electronic device is turned on and when the near field communication device is in a standby mode, then the group consisting of said at least one part of a volatile memory, said at least one register, and said at least one first circuit is powered by a first supply voltage of said at least one second communication module of the device.

[0009] According to one embodiment, said at least one first circuit comprises an internal communication bus of said device, and / or a state machine adapted to detect the state of said first module.

[0010] According to one embodiment, said device comprises power supply circuits comprising a battery, at least one first voltage regulator, and at least one node transmitting the first supply voltage to said at least one second communication module of the device.

[0011] According to one embodiment, when the electronic device is switched on and when the first near-field communication module is active, then all the circuits of the device, with which the first module is adapted to communicate, are powered by the first voltage regulator, the first voltage regulator being adapted to provide a second supply voltage equal to the first supply voltage from a third supply voltage provided by the battery.

[0012] According to one embodiment, when the device is switched off and when the near-field communication module is active, then all the circuits of the device, with which the first module is adapted to communicate, are powered by the first voltage regulator.

[0013] According to one embodiment, when said first near-field communication module is inactive then none of the circuits of the device, with which the first module is adapted to communicate, is powered by said power supply module.

[0014] According to one embodiment, said first supply voltage is between 1 and 1.5 V.

[0015] According to one embodiment, said power supply circuits of the device further comprise a second voltage regulator adapted to provide a fourth power supply voltage equal to the first power supply voltage from a third supply voltage supplied by the battery.

[0016] According to one embodiment, the first voltage regulator provides a first current equal to at least ten times a second current provided by the second voltage regulator.

[0017] According to one embodiment, when the device is switched off and when the first near-field communication module is in a standby mode, then all the circuits of the device, with which the first module is adapted to communicate, are powered by the second voltage regulator. Brief description of the drawings

[0018] These characteristics and advantages, as well as others, will be explained in detail in the following description of particular embodiments given without limitation in relation to the attached figures among which:

[0019] [Fig.l] represents, very schematically and in the form of blocks, an example of near-field communication;

[0020] [Fig.2] represents, very schematically and in the form of blocks, an embodiment of a device adapted to near-field communication technology;

[0021] [Fig.3] represents, schematically, in the form of blocks, and in a more detailed manner, part of the embodiment of [Fig.2];

[0022] [Fig.4] represents an electrical diagram, partially in block form, of an embodiment of a power supply module of the device of [Fig.2]; and

[0023] [Fig. 5] represents an electrical diagram, partially in block form, of another embodiment of a power supply module of the device of [Fig. 2]. Description of the embodiments

[0024] The same elements have been designated by the same references in the different figures. In particular, the structural and / or functional elements common to the different embodiments may have the same references and may have identical structural, dimensional and material properties.

[0025] For the sake of clarity, only the steps and elements useful for understanding the described embodiments have been shown and are detailed. In particular, the Near Field Communication (NFC) protocols and technologies will not be detailed exhaustively below.

[0026] Unless otherwise specified, when referring to two elements connected to each other, this means directly connected without intermediate elements other than conductors, and when referring to two elements connected (in English "coupled") to each other, this means that these two elements can be connected or be connected by means of one or more other elements.

[0027] In the following description, when referring to position qualifiers absolute, such as the terms "front", "back", "top", "bottom", "left", "right", etc., or relative, such as the terms "above", "below", "upper", "lower", etc., or orientation qualifiers, such as the terms "horizontal", "vertical", etc., are referred to unless otherwise specified to the orientation of the figures.

[0028] Unless otherwise specified, the expressions "approximately", "approximately", "sen "possibly", and "of the order of" mean within 10%, preferably within 5%.

[0029] [Fig.l] schematically represents a wireless communication, and more particularly, a near-field communication between electronic devices 1 (TERM) and 2 (CARD).

[0030] Near Field Communication (NFC) technologies enable high-frequency, short-range communications. Such systems exploit a radiofrequency electromagnetic field emitted by a device (terminal or reader) to communicate with another device (transponder or card).

[0031] In recent systems, the same device can operate in card mode or in reader mode (for example in the case of near-field communication between two mobile phones). It is then common for the devices to be powered by batteries and for their functions and circuits to be put on standby so as not to consume energy between periods of use. The devices must then be "waken up" when they are within range of each other.

[0032] We assume the case of the two electronic devices 1 and 2, in which, for example, the device 1 is a terminal, or reader, and the device 2 a transponder, but everything that will be described applies more generally to any system in which a transponder picks up an electromagnetic field radiated by a reader, terminal or terminal.

[0033] Depending on the applications, for communication, one of the devices operates in so-called reader mode while the other operates in so-called card mode, or the two devices communicate in peer-to-peer (P2P) mode. Each device comprises various electronic circuits 11 (NFC) and 12 (NFC), or NFC modules 11 and 12, for generating a radiofrequency signal emitted using an antenna of an oscillating / resonant circuit. The radiofrequency field generated by one of the devices 1 or 2 is picked up by the other device 2 or 1 which is within range and which also comprises an antenna. In certain applications, when a device is not communicating, it is switched to standby mode in order to reduce the energy consumed. This is particularly the case for battery-powered devices.When the first device 1 emits an electromagnetic field to initiate communication with the second device 2, this field is picked up by this second device 2 as soon as it is within range. This field is detected by the circuits 12 of the second device 2 which, if they are . on standby, are reactivated. This results in a variation of the load constituted by the circuits of the second device 2 on the resonant circuit for generating the field of the first device. In practice, the corresponding variation in phase or amplitude of the emitted field is detected by the first device 1 which then starts an NFC communication protocol with the second device 2. On the first device 1 side, it is detected in practice whether the amplitude of the voltage across the resonant circuit 12 falls below a threshold or whether the voltage across the resonant circuit has a phase shift greater than a threshold. Once the first device 1 has detected the presence of the second device 2 in its field, it starts a communication establishment procedure, implementing the transmission of requests by the first device 1 and responses by the second device 2.

[0034] During near-field communication, devices 1 and 2 are positioned within range of each other. More specifically, device 2 is positioned within range of device 1 in order to be able to pick up the electromagnetic field of device 1. For example, device 2 is positioned at a distance generally less than 10 cm from terminal 1. According to another example, device 2 is in mechanical contact with terminal 1.

[0035] The device 1 is a terminal which may be, for example, fixed or mobile. It is the device 1 which is responsible for initiating the communication. For example, the terminal 1 is a payment terminal or a mobile telephone.

[0036] The device 2 is a generally mobile transponder. According to a preferred embodiment, the transponder 2 is a microcircuit card (or smart card), for example a bank card or a transport card. Alternatively, the transponder 2 could be a mobile telephone or a connected object. The device 2 comprises different electronic circuits adapted to implement various commands sent by the device 1, such as for example, authentication circuits, cryptography circuits, etc. In particular, these different circuits consume more or less energy during the execution of a command sent by the device 1. The device 2 can comprise several different power supply modes in which certain circuits are powered while others are not; these different power supply modes are described in more detail in relation to FIGS. 2 and 3.

[0037] [Fig. 2] is a block diagram representing, very schematically and in block form, an example of architecture of an embodiment of an electronic device 30 of the type of device 1 or device 2 described in relation to [Fig. 1]. In other words, the electronic device 30 may be a transponder adapted to implement wireless communication, for example near field communication (NFC).

[0038] The electronic device 30 comprises a processor 31 (CPU) adapted to implement different processing of data stored in memories and / or provided by other circuits of the device 30.

[0039] The electronic device 30 further comprises different types of memories 32 (MEM), including at least one volatile memory and at least one register, generally several registers. The device 30 may further comprise, according to one example, a non-volatile memory, and a read-only memory. Each memory is adapted to store different types of data. The registers are, more particularly, adapted to store specific data such as state data of the device 30. By state data, we mean here data which provides information on the state of the device 30, or of these circuits and components.

[0040] The electronic device 30 further comprises power supply circuits 33 (ALIM). The circuits 33 manage the electrical power supply of the various circuits and components of the device 30. The circuits 33 comprise, for example, a battery, means for recharging the battery, voltage adaptation circuits, such as voltage regulators, etc. Embodiments of one of the power supply circuits are described in relation to FIGS. 4 and 5.

[0041] The electronic device 30 further comprises circuits 34 (NFC) adapted to implement near field communication, or near field communication module 34, or NFC module 34. The NFC module 34 comprises, for example, oscillating / resonant circuits, data transmission and reception circuits, data conversion circuits, etc.

[0042] The electronic device 30 further comprises circuits 35 (FCT) adapted to implement different functions of the device 30. The circuits 35 are diverse, and may comprise measurement circuits, data analysis circuits, sensors, etc.

[0043] The electronic device 30 further comprises input and output circuits 36 (I / O) of the device 30. The circuits 36 comprise connectors allowing the device 30 to transmit and receive data, display devices, etc.

[0044] As stated previously, the circuits 33 are adapted to manage the power supply, in voltage and in current, of the different circuits and components of the device 30. According to one embodiment, the circuits 33 comprise at least one circuit particularly adapted to manage the different power supply modes of the different circuits and components of the device 30. Indeed, all or part of the circuits and components of the device 30 can have several different power supply modes, such as, for example, a full power power supply mode and a low power power supply mode.

[0045] These different power supply modes can be implemented automatically. when the device 30 is in a certain configuration, or in a certain operating mode. The device 30 comprises at least two operating modes. The device 30 can be on or off. When the device 30 is on, all of its circuits and components can be used, and can be powered by the power supply circuits 33. When the device 30 is off, all of its circuits and components are supposed to be powered off, but some, such as the NFC module 34, are powered, for example with lower power to reduce energy consumption. The operating mode of the device 30 can be chosen by a user of the device 30.

[0046] Furthermore, the different power supply modes of certain circuits and components of the device 30 may have an influence on the power supply modes, or on the power supply, of other circuits and components of the device 30. In particular, and according to one embodiment, the NFC module 34 has several power supply modes which influence the power supply mode, and on the power supply, of circuits and components of the device 30.

[0047] The NFC module 34 comprises at least three power supply modes: an active power supply mode, a standby power supply mode, and an inactive power supply mode. When the NFC module 34 is in the active power supply mode, in other words the NFC module 34 is active, the NFC module 34 is available for use at any time. All of the circuits and components included in the NFC module 34 are likely to be powered; it is in this mode that the NFC module 34 is likely to consume the most power. When the NFC module 34 is in the standby power supply mode, in other words the NFC module is in standby, the NFC module 34 is expected to be able to provide a service comprising fewer functionalities, and therefore only a portion of the circuits included in the NFC module 34 is likely to be powered. In this mode, the NFC module 34 generally consumes less power than in the active power supply mode.When the NFC module 34 is in the inactive power mode, or hibernation mode, in other words when the NFC module 34 is inactive, only a minimal part of the circuits of the NFC module 34 is likely to be powered. It is in this power mode that the NFC module 34 consumes the least energy.

[0048] In addition, like the device 30, the NFC module 34 has several operating modes, and can be switched on or off. The operating mode of the NFC module 34 can be chosen, for example manually, by a user of the device 30.

[0049] The different power supply modes of the NFC module 34 can be put into different usage configurations of the device 30. The active mode of the NFC module 34 can be implemented when the NFC module 34 is switched on, whether the device 30 is on or off. The standby mode of the NFC module 34 can be implemented when the device 30 is on, and the NFC module 34 is on. The inactive mode can be implemented when the NFC module 34 is off, whether the device 30 is on or off, or when the NFC module 34 is on but the device 30 is off.

[0050] The implementation of the different power supply modes of the circuits influences the power supply of certain circuits and components of the device 30. This is described in more detail in relation to [Fig.3].

[0051] [Fig. 3] is a block diagram representing, very schematically and in block form, an example of architecture of a part of the electronic device 30 described in relation to [Fig. 2]. [Fig. 3] illustrates, more particularly, the NFC module 34 and its interactions with the other circuits and components of the device 30.

[0052] The NFC module 34 is adapted to interact with different circuits and components of the device 30.

[0053] The NFC module 34 is powered by a power Pwr supplied by the power supply circuits 33 (ALIM), and are adapted to provide at least State_NFC state information to the power supply circuits 33, for example via the bus 37 not shown in [Fig. 3]. More particularly, the NFC module 34 is adapted to inform the power supply circuits of the power supply mode in which it is operating at a given moment. Thus, the power supply circuits 33 are adapted to take into account the power supply mode of the NFC module 34 to power other circuits and device components 30. Detailed embodiments of the circuits 33 are described in relation to FIGS. 4 and 5.

[0054] The NFC module 34 is, furthermore, adapted to interact with circuits and components of the device 30 divided into two groups: the "always active" group 38 (ALW ON) and the "optional" group 39 (SW DOM).

[0055] The "always active" group 38 comprises the circuits and components of the device 30 necessary to ensure minimal operation of the NFC module 34. The circuits and components of the group 38 are powered by the power Pwr supplied by the circuits 33. According to one embodiment, the "always active" group 38 comprises, at least: - at least a part of a volatile memory 381 included in the memories 32 of the device 30; - several registers 382 included in the memories 32 of the device 30, and adapted to store state variables of the device 30; - 383 circuits (WUP) adapted to make the NFC module 34 active.

[0056] The circuits 383 include, for example, an internal communication bus, such as an I2C (Inter-Integrated Circuit) bus, a state machine adapted to indicate that a wireless communication field has been detected, or adapted to emit a field of wireless communication.

[0057] The "optional" group 39 comprises the circuits and components of the device 30 used to ensure normal operation of the NFC module 34, but which are not necessary to ensure the minimum operation of the NFC module 34. The circuits and components of the group 38 are powered by the power Pwr supplied by the circuits 33. According to one embodiment, the "optional" group 39 comprises, at least: - the processor 31 of the device 30; - the communication bus 37 of the device 30; and - clock signal generation circuits 391 (CLK) of the device 30.

[0058] In practice, a majority of, or even all, of the circuits and components of the device 30 are formed on the same plate or on the same substrate. The circuits and components of the "always active" 38 and "optional" 39 groups are isolated from each other by isolation circuits 40 (INS). The isolation circuits 40 are, for example, powered by the circuits 33 with the power Pwr. According to a variant, the isolation circuits 40 do not need to be powered.

[0059] When the NFC module 34 is active, the circuits and components of the "always active" 38 and "optional" 39 groups are powered by the circuits 33, receiving the power Pwr. The device 30 can be in card mode in near-field communication, but also, for example, in reader mode.

[0060] When the NFC module 34 is in standby, only the circuits and components of the "always active" group 38 are powered by the circuits 33, receiving the power Pwr. The circuits and components of the "optional" group 40 are not powered, and do not receive the power Pwr. The device 30 can only be in card mode in a near field communication, for example by having access to the latest state variables of the device 30, but cannot be in a reader mode.

[0061] When the NFC module 34 is inactive, none of the circuits and components of the "always active" 38 and "optional" 40 groups are powered, and do not receive the power Pwr. The device 30 cannot be in a card mode or in a reader mode. According to one embodiment, the NFC module 34 of the device 30 can, for example, still detect the presence of a field.

[0062] [Fig. 4] is an electrical diagram, partially in block form, of an embodiment of a power supply circuit 50 forming part of the power supply circuits 33 described in relation to FIGS. 2 and 3. The power supply circuit 50 is adapted to supply the "always active" 38 and "optional" 39 groups described in relation to [Fig. 3].

[0063] The power supply circuit 50 is shown connected to the "always active" 38 and "optional" 39 groups, which are themselves connected to the isolation circuit 40, to facilitate the Description. Groups 38 and 39, and isolation circuit 40 are not part of circuit 50.

[0064] The power supply circuit 50 comprises two output nodes OUT1 and OUT2. The node OUT1 makes it possible to power the circuits and components of the "always active" group 38, and the node OUT2 makes it possible to power the circuits and components of the "optional" group 39. The nodes OUT1 and OUT2 both provide the same supply voltage VPS, referenced to a reference potential, for example ground, not shown in [Fig. 4], to the "always active" groups 38 and "optional" groups 39. According to an exemplary embodiment, the voltage VPS is between 1 and 5 V, for example between 1 and 1.5 V, for example of the order of 1.25 V.

[0065] The power supply circuit 50 comprises two input nodes BAT and VPSIO. The BAT node provides electronic power from a battery of the circuits 33. More particularly, the BAT node provides a supply voltage VBAT greater than the VPS voltage. The VBAT voltage is for example greater than 1.5 V, for example of the order of 2.5 V. According to one example, the VBAT voltage is referenced to a reference potential, for example ground. According to one embodiment, the VPSIO node is a power supply node used to power communication nodes of the NFC module 34. More particularly, the VPSIO node is adapted to power an internal communication circuit of the device 30. The VPSIO node is adapted to directly provide the VPS voltage, i.e. without needing to use a voltage regulator circuit. According to one example, the VPSIO node does not provide voltage when the device 30 is switched off.

[0066] The power supply circuit 50 further comprises a bandgap voltage regulator circuit 501. The circuit 501 comprises an input node connected, preferably connected, to the BAT node, and an output node connected, preferably connected, to a REF node. The circuit 501 provides a reference voltage from the voltage delivered by the battery at the BAT node.

[0067] The power supply circuit 50 further comprises two voltage regulators 502 and 503. The voltage regulators 502 and 503 each comprise two input nodes connected, preferably connected, to the node BAT and REF. The voltage regulator 502, respectively 503, comprises an output node connected, preferably connected, to the output node OUT1, respectively OUT2. The voltage regulators 502 and 503 are dimensioned to provide, from the voltage delivered by the node BAT, the voltage VPS. The voltage regulator 502 is dimensioned to provide, on the node OUT2, a current 12 lower than the current 13 provided by the voltage regulator 503 on the node OUT3. According to one example, current 12 is at least ten times lower than current 13. According to one example, current 12 is of the order of 2 mA, and current 13 is of the order of 60 mA.

[0068] Each voltage regulator 502, 503 comprises a transistor TP2, TP3, and an operational amplifier AO2, AO3. According to one example, the transistors TP2 and TP3 are P-channel metal-oxide gate field effect transistors, also called PMOS transistors.

[0069] A first conduction terminal of the transistor TP2 is connected, preferably connected, to the node BAT, and a second conduction terminal of the transistor TP2 is connected, preferably connected, to the node OUT1. The gate of the transistor TP2 is connected, preferably connected, to an output of the operational amplifier AO2. The operational amplifier AO2 comprises an inverting input (-) connected, preferably connected, to the REF node, and a non-inverting input (+) connected, preferably connected, to the OUT2 node.

[0070] A first conduction terminal of the transistor TP3 is connected, preferably connected, to the node BAT, and a second conduction terminal of the transistor TP3 is connected, preferably connected, to the node OUTL. The gate of the transistor TP3 is connected, preferably connected, to an output of the operational amplifier AO3. The operational amplifier AO3 comprises an inverting input (-) connected, preferably connected, to the REF node, and a non-inverting input (+) connected, preferably connected, to the OUT3 node.

[0071] The circuit 50 further comprises two switches 504 and 505 adapted to define by which input node of the circuit 50, the groups 38 and 39 are supplied. The switch 504 connects, preferably connects, the nodes VPSIO and OUTL. The switch 505 connects, preferably connects, the nodes OUT1 and OUT2. The switches 504 and 505 are controlled by signals (not shown in [Fig.4]) whose values ​​are defined by the different supply modes of the NFC module 34.

[0072] The operation of circuit 50 is as follows.

[0073] When the device 30 is turned on, and the NFC module 34 is active, all the circuits and components of the "always active" 38 and "optional" 39 groups are powered by the battery. The switch 505 is then conducting, and the switch 504 is not conducting. This configuration is the same, if the device 30 is turned off, and if the circuits 34 are in an active power supply mode.

[0074] According to an alternative embodiment, when the device 30 is switched on, and the NFC module 34 is active, all the circuits and components of the "always active" 38 and "optional" 39 groups are powered by the VPSIO node. The switch 504 is then conducting, and the switch 505 is not conducting.

[0075] When the device 30 is turned on, and the NFC module 34 is in standby, only the circuits and components of the "always active" group 38 are powered, and are powered by the VPSIO node. The circuits and components of the "optional" group 39 are not powered. The switch 504 is then conducting, and the switch 505 does not conduct.

[0076] When the device 30 is off, and the NFC module 34 is in standby, only the circuits and components of the "always active" group 38 are powered, and they are powered by the battery. The circuits and components of the "optional" group 39 are not powered. The switches 504 and 505 do not conduct.

[0077] When the NFC module 34 is inactive, whether the device 30 is on or off, the circuits and components of the "always active" 38 and "optional" 39 groups are not powered.

[0078] An advantage of this embodiment is that using the VPSIO node to power the circuits and components of the "always active" group 38 when the device 30 is turned on and when the module 34 is in an active power supply mode, makes it possible to reduce the power consumption of the device 30. Indeed, this embodiment makes it possible not to use the voltage regulator 502, and therefore to save its current consumption. According to an exemplary embodiment, this embodiment makes it possible to reduce the current consumption by approximately 15 pA, and to reduce the consumption from approximately 35 pA to approximately 20 pA.

[0079] [Fig. 5] is an electrical diagram, partially in block form, of an embodiment of a power supply circuit 60 forming part of the power supply circuits 33 described in relation to FIGS. 2 and 3. The power supply circuit 60 is adapted to supply the "always active" 38 and "optional" 39 groups described in relation to [Fig. 3],

[0080] Circuit 60 is similar to and has common elements with circuit 50 described in relation to [Fig.4]. The elements common to circuits 60 and 50 are not described in detail again here, and only the differences between circuits 50 and 60 are highlighted.

[0081] Like the power supply circuit 50, the power supply circuit 60 is shown connected to the "always-on" 38 and "optional" 39 groups described in connection with [Fig. 3], which are themselves connected to the isolation circuit 40, for ease of description. These groups 38 and 39, and the isolation circuit 40 are not part of the circuit 50.

[0082] Unlike circuit 50, circuit 60 only includes voltage regulator 503, and does not include voltage regulator 502. Power supply by voltage regulator 502 is replaced by power supply by the VPSIO node.

[0083] The operation of circuit 60 is as follows.

[0084] When the device 30 is turned on, and the NFC module 34 is active, all the circuits and components of the "always active" 38 and "optional" 39 groups are powered by the battery. The switch 505 is then conducting, and the switch 504 is not conducting. This configuration is the same, if the device 30 is turned off, and if the circuits 34 are in an active power supply mode.

[0085] According to an alternative embodiment, when the device 30 is switched on, and the NFC module 34 is active, all circuits and components in the "always active" 38 and "optional" 39 groups are powered by the VPSIO node. Switch 504 is then conductive, and switch 505 is not conductive.

[0086] When the device 30 is turned on, and the NFC module 34 is in standby, only the circuits and components of the "always active" group 38 are powered, and are powered by the VPSIO node. The circuits and components of the "optional" group 39 are not powered. The switch 504 is then conducting, and the switch 505 does not conduct.

[0087] When the device 30 is off, and the NFC module 34 is in standby, only the circuits and components of the "always active" group 38 are powered, and are powered by the VPSIO node. The circuits and components of the "optional" group 39 are not powered. The switch 504 is then on, and the switch 505 does not conduct.

[0088] When the NFC module 34 is in an inactive mode, whether the device 30 is on or off, the circuits and components of the "always active" 38 and "optional" 39 groups are not powered.

[0089] According to an alternative embodiment, when the device 30 is switched on, and the NFC module 34 is inactive, only the circuits and components of the "always active" group 38 are powered, and are powered by the VPSIO node. The circuits and components of the "optional" group 39 are not powered. The switch 504 is then conducting, and the switch 505 does not conduct.

[0090] An advantage of this embodiment is that it saves the space occupied by the voltage regulator 502. The device 30 may be, in this case, an Internet of Things device, i.e. a connected object.

[0091] Various embodiments and variations have been described. Those skilled in the art will understand that certain features of these various embodiments and variations could be combined, and other variations will occur to those skilled in the art.

[0092] Finally, the practical implementation of the embodiments and variants described is within the reach of those skilled in the art from the functional indications given above.

Claims

Claims

1. Electronic device (30) comprising: - a first near-field communication module (34); - at least one second communication module; - at least one part of a volatile memory (381); - at least one register (382); and - at least one first circuit (383) adapted to make said near-field communication module (34) active, wherein when the electronic device (30) is switched on and when the near-field communication device (34) is in a standby mode, then the group composed of said at least one part of a volatile memory (381), said at least one register (382), and said at least one first circuit (383) is powered by a first supply voltage (VPS) of said at least one second communication module of the device (30); - power supply circuits (33; 50; 60) comprising; ° a battery; ° at least one first voltage regulator (503);° at least one node (VPSIO) transmitting the first supply voltage (VPS) of said at least one second communication module of the device (30); and ° a second voltage regulator (502) adapted to provide a fourth supply voltage equal to the first supply voltage (VPS) from a third supply voltage (VBAT) provided by the battery.;

2. Device according to claim 1, wherein said at least one first circuit (383) comprises an internal communication bus of said device, and / or a state machine adapted to detect the state of said first module (34).

3. Device according to claim 1 or 2, wherein when the electronic device (30) is switched on and when the first near-field communication module (34) is active, then all the circuits of the device (30), with which the first module (34) is adapted to communicate, are powered by the first voltage regulator (503), the first voltage regulator (503) being adapted to provide a second supply voltage equal to the first supply voltage (VPS) from a third supply voltage (VBAT) provided by the battery.

4. A device according to any one of claims 1 to 3, wherein when the device (30) is off and when the near field communication module (34) is active, then all circuits of the device (30), with which the first module (34) is adapted to communicate, are powered by the first voltage regulator (503).

5. Device according to any one of claims 1 to 4, wherein when said first near field communication module (34) is inactive then none of the circuits of the device (30), with which the first module (34) is adapted to communicate, is powered by said power supply module (30; 50; 60).

6. Device according to any one of claims 1 to 5, wherein said first supply voltage (VPS) is between 1 and 1.5 V.

7. Device according to any one of claims 1 to 6, in which the first voltage regulator (503) provides a first current (13) equal to at least ten times a second current (12) provided by the second voltage regulator (502).

8. A device according to any one of claims 1 to 7, wherein when the device (30) is turned off and when the first near-field communication module (34) is in a standby mode, then all circuitry of the device (30), with which the first module (34) is adapted to communicate, is powered by the second voltage regulator (503).

9. A method of powering an electronic device (30) comprising: - a first near-field communication module (34); - at least one second communication module; - at least one part of a volatile memory (381); - at least one register (382); and - at least one first circuit (383) adapted to make said near-field communication module (34) active, wherein when the electronic device (30) is switched on and when the near-field communication device (34) is in a standby mode, then the group composed of said at least one part of a volatile memory (381), said at least one register (382), and said at least one first circuit (383) is powered by a first supply voltage (VPS) of said at least one second communication module of the device (30); - power supply circuits (33; 50; 60) comprising; ° a battery; ° at least one first voltage regulator (503); ° at least one node (VPSIO) transmitting the first supply voltage (VPS) of said at least one second communication module of the device (30); and ° a second voltage regulator (502) adapted to provide a fourth supply voltage equal to the first supply voltage (VPS) from a third supply voltage (VBAT) provided by the battery.

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