HK1080959A - A method and a system for determining the power consumption in connection with an electronic device, and an electronic device - Google Patents

Description

Method and system for determining power consumption associated with an electronic device, and electronic device

The invention relates to a method for determining power consumption in an electronic device to which a peripheral is connected and from which power is supplied to the peripheral. The invention also relates to a system comprising an electronic device with means for connecting a peripheral device and means for supplying power to the peripheral device, and the system further comprises means for determining power consumption. Furthermore, the invention relates to an electronic device having means for connecting a peripheral device, means for supplying power to the peripheral device and means for determining the power consumption of the peripheral device. The invention further relates to a peripheral device having means for connecting the peripheral device to an electronic device, the peripheral device being arranged to be supplied with the power required for using the peripheral device from the electronic device.

Currently, several such electronic devices are used, which can connect different peripheral devices, for example, in order to extend the properties of the electronic devices and to generate auxiliary functions. For example, a peripheral device such as a connector card (e.g., a PCMCIA card) may be connected to a laptop computer to connect the laptop computer to a local area network, a landline or wireless telephone network, or the like. In addition, the peripheral device can be used to expand the memory of a laptop computer, connect it to an external fixed disk, CDROM station, etc.

Among them, MultiMediaCard^TMThe consortium is developing a standard for memory expansion boards (MultiMediaCard)^TM；MultiMediaCard^TMIs a registered trademark of Infineon Technologies AG corporation). These memory expansion boards can be used in various portable electronic devices such as wireless communication devices and communicator type devices to expand memory capacity.

Since the peripheral device can be connected to various devices, the power consumption of the peripheral device should not exceed the maximum power that the electronic device can provide to the peripheral device. Otherwise, operation of the peripheral and/or electronic devices may be disturbed and even the electronic devices may overheat. On the other hand, the requirements for power consumption of different peripheral devices may be very different, wherein the manufacturer of the electronic device should provide the maximum power consumption in the power supply to which the peripheral device is connected. It is known in solutions such as the Nokia communicator 9110/9210 to utilize a relatively efficient regulator to provide power to peripheral connections of an electronic device, for example, approximately 150 mA/3V. Such a high efficiency regulator is a relatively bulky component that may cause placement problems, particularly in portable electronic devices. It is not necessary to provide maximum power consumption in such an electronic device, and its user does not use such a peripheral device with the electronic device whose power consumption is close to the maximum power consumption of the peripheral device for which the electronic device is designed. On the other hand, another user of a similar electronic device may use a peripheral device whose power consumption is approximately the maximum power consumption of the peripheral device for which the electronic device is designed.

In some electronic devices and peripheral devices to be connected to these electronic devices, the operating voltage is selected at a stage when the peripheral device is turned on, for example, when the electronic device is turned on or the peripheral device is connected. Thus, signaling will be made between the electronic device and the peripheral device, causing the electronic device to determine the level of operating voltage required by the peripheral device and to select an operating voltage for the operating voltage line of the peripheral device that is appropriate for the peripheral device.

In the MultiMediaCard Association described, it has been a MultiMediaCard^TMThe power consumption of the type memory card suggests a maximum limit. Thus, in the electronic device supporting the standard, a prescribed maximum power is supplied to the peripheral device. Also, MultiMediaCard^TMThe power consumption of the type memory card should therefore not exceed this prescribed maximum limit. Such an arrangement is difficult, for example, because the power consumption of new memory cards being developed is limited to this maximum value, which can be an obstacle to implementing such memory cards that cannot have their power consumption less than the maximum limit value selected. If the maximum limit value is set so high that the power consumption of other later improved memory cards is likely to be less than this value, this means that a relatively efficient and large regulator must be used in the electronic device.

The power consumption of a peripheral device is generally proportional to the clock frequency used in the peripheral device, where an increase in the clock frequency will result in an increase in power consumption. The clock frequency of the peripheral device may be reduced in a corresponding manner to reduce power consumption, if other functions of the peripheral device are considered possible. However, the operating rate of the peripheral device will therefore be reduced, which is not desirable. At the same time, the bus width used in a peripheral device also has a large effect on how much power is consumed in the peripheral device.

It is an object of the invention to provide an improved method and system for determining an appropriate power consumption in each case. It is a further object of the invention to provide an electronic device and a peripheral device applying such a method. The invention is based on the idea to determine at least a first and a second maximum value for the power consumption, wherein the electronic device and the peripheral device set the power consumption to a value between these first and second maximum values. In this way, the peripheral device can adjust its power consumption to suit the situation, for example, in different operating situations. The method according to the invention is essentially characterized in that: at least a first maximum value and a second maximum value higher than the first maximum value are determined for the power consumption, and the maximum value of the power consumption of the peripheral device is set between the electronic device and the peripheral device to a value substantially between said first and second maximum values. The system according to the invention is essentially characterized in that: at least a first maximum value and a second maximum value higher than the first maximum value are defined for the power consumption and the means for determining the power consumption comprise means for setting the maximum value of the power consumption of the peripheral device to a value between said first maximum value and said second maximum value. The electronic device according to the present invention is basically characterized in that: at least a first maximum value and a second maximum value higher than the first maximum value are defined for the power consumption and the means for determining the power consumption comprise means for setting the maximum value of the power consumption of the peripheral device to a value between said first maximum value and said second maximum value. Moreover, the peripheral device according to the present invention is basically characterized in that: a first maximum value and a second maximum value higher than the first maximum value are defined for the power consumption and the means for determining the power consumption comprise means for setting the maximum value of the power consumption of the peripheral device to a value between said first maximum value and said second maximum value.

The present invention shows significant advantages over prior art solutions. By the method according to the invention, the use of unnecessarily large regulators in electronic devices can be avoided, which reduces the costs and in some cases the size of the electronic devices, and on the other hand avoids the problem of heating caused by high power consumption. Furthermore, power consumption is reduced, which is particularly advantageous for portable devices. With the present invention, since the power consumption of the peripheral device can be adjusted and set to a value suitable for each use case, the connection of the peripheral device also has flexibility. Also, the clock frequency and bus width of the peripheral devices may also be varied in the system according to the preferred embodiments of the present invention. Furthermore, the present invention makes it easier to develop new peripherals to operate with the electronic device, and makes it possible to operate existing peripherals with the new electronic device to be developed. With the solution according to the invention, an improvement can be achieved in the user-friendliness of the electronic device, for example in the case of a peripheral device which cannot operate completely at low level of power consumption, the peripheral device can inform the electronic device about the change. In this way, the electronic device can shut down (disconnect) the peripheral device in an appropriate manner and notify the user thereof.

The invention will be described in more detail below with reference to the accompanying drawings, in which

Figure 1 shows a system according to a preferred embodiment of the invention in a simplified block diagram,

figure 2 shows in a simplified manner a system according to a second preferred embodiment of the invention,

figure 3 shows in a simplified manner signalling in a method according to a preferred embodiment of the invention,

fig. 4 shows a peripheral device according to another preferred embodiment of the invention in a simplified block diagram.

In the system according to the preferred embodiment of the invention shown in fig. 1, the electronic device 1 is exemplified as a wireless communication device. In this example, the peripheral device 2 is a memory card, for example, compliant with a MultiMediaCard^TMA standard memory card. However, it is apparent that the present invention is not limited to only such electronic devices and peripheral devices, but is also applicable to other electronic devices and peripheral devices. For example, peripheral device 2 may be an interface card or other device. The electronic device 1 comprises a control block 3 comprising one or more devices such as a Microcontroller (MCU)) Such a processor. Furthermore, the electronic device 1 comprises a memory 4, a user interface 5 and means 6 for performing the functions of a mobile station, such as a GSM and/or UMTS mobile communication device. The user interface 5 preferably comprises a display, a keypad and audio means in a known manner as described. For connecting the peripheral device 2, the electronic device 1 has a connecting means 7, which connecting means 7 comprises at least one connector 8 and the necessary I/O block 9, for example for connecting the bus of the peripheral device 2 and the electronic device 1 to each other.

The peripheral device also has corresponding connection means 10 for connecting the peripheral device 2 to the electronic device 1. The peripheral device connection means 10 comprise at least one connector 11 and an I/O block 12, which connector 11 is connectable to the connector 8 of the electronic device 1. The power settings provided to the peripheral device 2 are from the electronic device 1 via the connectors 8, 11. The I/O block is used for communication between the electronic device 1 and the peripheral device 2. This can be done as a parallel data transfer or a serial data transfer. For example, said according to MultiMediaCard^TMThe canonical peripheral provides serial data transfer. However, the format of the data transmission between the electronic device 1 and the peripheral device 2 is not important in view of the present invention.

The peripheral device 2 further comprises means, such as a processor 13, for controlling the functions of the peripheral device 2. The peripheral devices also include memory 14, such as read/write memory (RAM) for storing data, and read-only memory (ROM, NVRAM) for storing program code. For example, the processor is responsible for controlling the I/O blocks in the transfer of data between the peripheral device 2 and the electronic device 1. At least a first maximum and a second maximum of the power consumption used in the method according to the invention are also stored in the memory 14 of the peripheral device. The peripheral device further comprises means for generating one or more clock signals required for the operation of the processor, such as a clock generator 16.

The following describes the operation of the method according to a preferred embodiment of the invention in the system shown in fig. 1. For example, information about whether the peripheral device 2 is placed in the connector 8 of the connection means of the electronic apparatus is transmitted to the electronic apparatus 1 via the I/O block. For example, the above operation may be performed by providing the I/O blocks 9, 12 with a detection line 15 whose state changes when the peripheral device 2 is placed in the connector 8. In a preferred embodiment of the invention, the detection line 15 is implemented such that the detection line 15 is set in the logic 1 state by means of a pull-up resistor R in the electronic device 1. In the system of fig. 1, the change of state is implemented in such a way that: peripheral 2 grounds sense line 15, wherein the state of sense line 15 changes to a logic 0 state. This change of state is detected in the electronic device 1, for example in such a way that it causes an interrupt in the control block 3, in which the corresponding interrupt service routine is run and the peripheral initialization function is started. After the operating voltage has been coupled to the peripheral device, the processor 13 of the peripheral device 2 will start running its own initialization operation. For example, the power consumption of the peripheral device 2 is set to a default value, which in the preferred embodiment is a power consumption value according to a first maximum limit value. In this context, it is assumed that the first maximum limit value is lower than the second maximum limit value. The processor also sets the frequency of the clock generator 16 to correspond to the power consumption value. Typically, the frequency of the clock generator is set to a minimum value. In all peripherals 2 it is not necessary to control the frequency of the clock generator 16, wherein the clock generator 16 cannot be used to control power consumption.

In the operation of initializing the peripheral device performed by the electronic device 1, it is preferable to check the type of the peripheral device 2, which may affect the type of the initialization operation to be performed. However, this specification will discuss only the operations necessary for the present invention. The signalling to be performed in the method according to the preferred embodiment of the invention is illustrated in a simplified manner in fig. 3. After the determination of the type of peripheral device 2, the first and second maximum limit values of the power consumption already stored on the card are determined. In this way, the maximum limit value read message is preferably transmitted from the electronic device 1 to the peripheral device 2. This is illustrated by arrow 301 in the graph of fig. 3. The message is received in the peripheral device 2 and preferably checked for its content in the processor 13. In response to this message, the processor 13 reads the first maximum limit value and the second maximum limit value from the memory 14 (block 302 in fig. 3). If there are more than two maximum limit values, the number of maximum limit values is preferably stored in a memory device, wherein the processor 13 reads all values of the maximum limit values from the memory 14. Thereafter, the processor 13 generates a reply message containing the requested information (e.g., the first and second maximum limits, and if necessary, the number of maximum limits) (block 303). In the case of a plurality of maximum limit values, it is preferred that values of other maximum limit values are also included in the message. The message is transmitted to the electronic device via the I/O blocks 9, 12 (arrow 304), wherein the control block reads the information of the received messages and stores them, if necessary, in the memory 4 of the electronic device.

After the maximum limit value of the power consumption supported by the peripheral device is known in the electronic device 1, the adjustment of the power consumption of the peripheral device can be started, if necessary. It is assumed that the electronic device 1 is capable of providing power to the peripheral device 2 corresponding to the second maximum limit value. Thus, a power control message is transmitted from the electronic device 1 to the peripheral device 2 (arrow 305). The power control message indicates a power consumption value to be set to the maximum value of the peripheral device 2, e.g. the second maximum limit value. The processor 13 of the peripheral device checks the type of message received and, after determining that it is a power control message, reads the maximum value of power consumption indicated in the message (block 306). The processor 13 of the peripheral device then sets the operating frequency, such as the clock generator 16, to a value corresponding to the maximum value of this power consumption, for example to the highest possible frequency. In some embodiments, the bus width within the processor may also be varied according to the maximum value for power consumption. Also, the peripheral device 2 preferably informs the electronic device 1 that the power consumption has been limited to the requested value (arrow 307).

If the electronic device 1 cannot supply power to the peripheral device 2 at the second maximum limit value, or if for other reasons the electronic device 1 tends to set the maximum value of the power consumption lower than the second maximum limit value, it is possible to perform signalling by which the electronic device 1 and the peripheral device 2 try to find such a maximum limit value of the power consumption that is suitable for the situation. For example, it may be performed in such a way that: the electronic device 1 selects between the first and the second maximum limit value a value which appears to the electronic device 1 as the maximum value. Information about this limit value is transmitted to the peripheral device 2, wherein the proposed value is checked 13, and if it is found acceptable, the information is transmitted to the electronic device 1. If the peripheral device 2 cannot set its own power consumption to such a level corresponding to the suggested maximum value, the peripheral device 2 will suggest a lower value between the first and second maximum values. If this value appears to be possible to the electronic device 1, the electronic device 1 transmits this information to the peripheral device 2, where the power consumption is set to this value. If the value suggested by the peripheral device 2 is not suitable, the electronic device 1 may conveniently select and report to the peripheral device 2 a further value, which is preferably a lower value, which is however at least equal to the first maximum limit value. The above steps are repeated until such a power consumption value is found which is suitable for both the electronic device 1 and the peripheral device 2. Sometimes it may happen that the only suitable value is the first maximum value, wherein no power consumption needs to be adjusted because this value is the default value.

It may be necessary to change the value of the power consumption during operation of the electronic device 1 and the peripheral device 2 connected thereto. For example, if the peripheral device is a transceiver card, such as a mobile station card or modem card, it may be necessary to significantly change the power consumption limit of the peripheral device 2, for example during transmission. Thus, at a stage when for example the peripheral device 2 detects that a change in power consumption is required, it sends a message to the electronic device 1 and proposes a new power consumption value, but which is still within the range between the first and second maximum values. Message exchange is performed between the electronic device 1 and the peripheral device 2 by applying the above-described principle to control power consumption of the peripheral device as needed. When the demand for power consumption changes again, new adjustments to power consumption may be made.

The need to change the power consumption of the peripheral device may also arise in the electronic device 1. For example, when the operation of the electronic apparatus 1 is changed to the power saving mode, or when the power of a battery (not shown) in the electronic apparatus is reduced, the electronic apparatus 1 may control the peripheral apparatus 2 to shift to a lower power consumption state.

It is also possible to connect a peripheral device according to the invention to such an electronic device 1, which is not capable of regulating power consumption. In this way, the peripheral device 2 sets a default value (i.e., preferably the first maximum limit value) as the power consumption value. Therefore, the peripheral device according to the invention can also be connected to an electronic device 1 in which electronic device 1 the steps of the method according to the invention are not performed to control the power consumption of the peripheral device 2.

It is mentioned above that two or more different maximum limit values are used as the maximum value of the power consumption. In this context, it is assumed that the further maximum limit value is between the first and the second maximum limit value. These different maximum limits are possible, for example in such applications where different bus widths may be selected among the peripheral devices. For example, in the system of fig. 2, the width of the bus connecting between the peripheral device and the electronic device may be selected to be any of three values, 8, 16 or 32 bits. At the same time, the bus width selected for the connection in the preferred embodiment is also used in the internal bus 17 of the peripheral device 2. Typically, the wider the bus used, the higher the power consumption. Thus, assuming that it is preferred that the bus width during the start-up phase is 8 bits, the electronic device 1 and the peripheral device 2 may negotiate to use a further bus width, i.e. to change the maximum defined value of the power consumption. This can be achieved by applying the principles described above. It is clear that the bus widths are only a few of the non-limiting examples of bus widths.

The frequency of the clock generator 16 of the peripheral device does not have to be adjusted in a stepless manner, but a value may be selected for this frequency from a plurality of predetermined values. In this way it is possible to store in the peripheral device maximum limit values for the power consumption corresponding to these different frequencies as said maximum limit values, or as long as a first maximum limit value (lowest power consumption) and a second maximum limit value (highest power consumption) are stored, it is possible to perform a message exchange between the electronic device 1 and the peripheral device to adjust a suitable power consumption limit value, as described above.

Thus, for example, the power consumption of the peripheral device 2 may be adjusted by changing the clock frequency and/or the bus width, but it is apparent that other methods for adjusting the power consumption are known and may be applied with the present invention. If the operating voltage of the peripheral device 2 does not have to be a given constant value, the power consumption can also be controlled by controlling the operating voltage. Peripheral devices are known in which the operating voltage can be chosen to be, for example, 3V, 3.3V or 5V. Another example will be mentioned herein of the possibility of controlling the power consumption of a peripheral device, i.e. controlling the current consumption of a peripheral device.

Furthermore, if the power consumption of the peripheral device 2 is independently adjustable, the power consumption of the peripheral device 2 can also be adjusted by changing the clock frequency of the bus connected between the peripheral device and the electronic device. The clock frequency of the bus may be changed, for example, by the electronic device 1 and/or the peripheral device 2, if desired. The electronic device 1 controls a clock generator (not shown) which generates timing signals for the bus according to the same principles as described above.

In a preferred embodiment of the invention, at least a part of the memory of the peripheral device 2 is divided into two or more memory blocks to form a so-called memory bank. In this way, one or more of these memory blocks may be selected for use in the peripheral device, for example, based on a maximum power consumption value defined for the peripheral device 2. With higher power consumption values, more memory blocks may be used than with lower power consumption values. Fig. 4 shows an example of such a peripheral device structure. In the peripheral device 2 shown in fig. 4, the memory 14 has four memory blocks 14a, 14b, 14c, 14d, but it is clear that in practical applications the number of memory banks may also be different from four within the scope of the invention. In order to use the memory blocks 14a-14d and remove them from service, connection lines 18a-18d are preferably provided from the processor 13 to couple, for example, an operating voltage to the desired memory blocks 14a-14d, or to switch each memory block 14a-14d to an active mode or a power-saving mode using these coupled lines. The power consumption of the peripheral device 2 may also be controlled in the manner described above, instead of or in addition to the method of controlling power consumption described herein above.

In the electronic apparatus 1, the power control may be performed, for example, by supplying the electronic apparatus 1 with a power supply whose output voltage can be changed. Thus, in the electronic apparatus 1, the operating voltage to be supplied to the peripheral device is selected to be a voltage value corresponding to the power consumption at that time.

The method according to the invention can also be applied in embodiments of various content for use with the electronic device 1, for example in the following manner. It is possible to use as peripheral device 2 a memory card in which content can be stored, for example in compliance with a MultiMediaCard^TMStandard defined cards. In this document, content refers to data files, applications, electronic books, audio-visual information such as music, video, and the like. For example, content providers store such content in memory cards. In this way, the memory card 2 is connected to an electronic apparatus having a device for transferring its content to the memory card 2. Therefore, before starting the storage, the electronic apparatus and the memory card 2 preferably set the power consumption of the memory card to a value corresponding to the second maximum limit value. This is possible because in such an electronic apparatus 1 for storing contents, the power consumption of the memory card is hardly significant, but the electronic apparatus 1 can supply sufficient power to the memory card 2. Since the clock frequency and/or the bus width of the memory card can be set to the maximum value, storage can be performed at the maximum rate. At the same time, the user can select the desired position,the content stored on the memory card 2 can also be checked at the maximum rate in order to check for possible memory defects. Thanks to this maximum storage and/or checking rate, the content production rate of the electronic device 1 can be increased compared to prior art methods.

In a corresponding manner, the power consumption of the memory card 2 can be set to a level suitable for the electronic device 1, for example to the lowest possible power consumption, at the stage of using the content stored on the memory card 2 in the electronic device 1. Thus, when applying the method of the present invention, it is not necessary to limit the content production rate according to the maximum power consumption value possible in the use of the content.

Since the method according to the invention can also be used for power control of peripheral devices, peripheral devices 2 can be connected to various electronic devices. In some electronic devices, it is only possible to provide the peripheral devices with power (voltage and current) corresponding to the minimum power consumption, wherein the electronic device 1 does not require a large regulator, nor does it require an increase in the size of the electronic device because of the space required by the large regulator. On the other hand, it is not necessary to limit the power consumption in the peripheral device 2 to be developed, since an appropriate power consumption value can be negotiated by the electronic device and the peripheral device. In this way, if a peripheral device is connected to such an electronic device that is capable of supplying relatively high power to the peripheral device connection, the peripheral device can be used as efficiently as possible (with a high clock frequency/a large bus width). Even such peripheral devices will operate at a lower power consumption during the initialization phase before selecting an appropriate power consumption value. In the system according to the invention, it can be provided for use in peripheral devices that are developed in the future and require higher power in the electronic device. However, cards with high power consumption need not be considered in the design of all electronic devices.

It is clear that the steps taken in setting the power consumption can also be implemented in other ways than the above-described exchange of signals in the form of messages. For example, the connection means 7, 10 may have a connection line for setting the power consumption of the peripheral device. Furthermore, the invention can also be applied in such a way that certain alternative (permissible) values are determined for said maximum limit value, wherein the first maximum limit value and the second maximum limit value for each peripheral device are selected from these alternative limit value sets.

It should also be mentioned that the peripheral device 2 need not be a peripheral device in the form of a card, but that the peripheral device 2 used may also be another device that can be connected to the electronic device 1. One non-limiting example of such a peripheral device to be mentioned is a camera connected to e.g. a wireless communication device, a computer, etc. Thus, by controlling the power consumption, it is possible to affect the performance of the camera. For example, the rate at which images are updated on a display of an electronic device may be reduced, in analogy with lower power consumption, which is lower than higher power consumption. In this way, the electronic apparatus 1 can preferably set the power consumption of the camera serving as the peripheral apparatus 2 based on how high the electronic apparatus 1 can supply to the peripheral apparatus. In a preferred embodiment of the invention, the user of the electronic device 1 can also set a maximum limit value for the power consumption, wherein the user can, for example, lower the maximum limit value to extend the operating time of the electronic device, if desired.

It is obvious that the invention is not limited solely to the above-described embodiments but it can be modified within the scope of the appended claims.

Claims (26)

1. A method for determining power consumption in an electronic device (1) to which a peripheral device (2) is connected, wherein power is supplied by the electronic device (1) to the peripheral device (2), characterized by: at least a first maximum value and a second maximum value higher than the first maximum value are determined for the power consumption, and the maximum value of the power consumption of the peripheral device (2) is set between the electronic device (1) and the peripheral device (2) to a value substantially between said first and second maximum values.

2. The method of claim 1, wherein: the first maximum limit value is used as a default value for the power consumption, wherein the power consumption of the peripheral device (2) is set during the start-up phase to be substantially not higher than the first maximum limit value.

3. The method according to claim 1 or 2, characterized in that: the second maximum limit value is used as the maximum allowable limit value for power consumption.

4. A method according to claim 1, 2 or 3, characterized in that: -transmitting a message between the electronic device (1) and the peripheral device (2) for setting the power consumption of the peripheral device to a value substantially between said first maximum limit value and said second maximum limit value.

5. The method according to any one of claims 1 to 4, wherein: -storing at least one content in the peripheral device (2) for use with the electronic device (1), wherein during the storage phase of the content the power consumption set for the peripheral device (1) is a value corresponding to said second maximum limit value, and during the use phase of the content the power consumption set for the peripheral device (2) is a value corresponding to said first maximum limit value.

6. The method according to any one of claims 1 to 5, wherein: at least one clock signal is generated in the peripheral device (2) and the power consumption of the peripheral device (2) is controlled by adjusting the frequency of the at least one clock signal.

7. The method according to any one of claims 1 to 6, wherein: the peripheral device (2) comprises at least one bus and the power consumption of the peripheral device (2) is controlled by controlling the bus width of the peripheral device (2).

8. The method according to any one of claims 1 to 7, wherein: the peripheral device (2) has two or more memory blocks (14a-14d), wherein the power consumption of the peripheral device (2) is controlled by controlling the number of memory blocks (14a-14d) processed by the peripheral device (2) substantially simultaneously.

9. A system comprising an electronic device (1), the electronic device (1) having means (7) for connecting a peripheral device (2) and means (8) for supplying power to the peripheral device (2), and the system comprising means (7, 10, 14) for determining power consumption, characterized in that: at least a first maximum value and a second maximum value higher than the first maximum value are defined for the power consumption, and the means for determining the power consumption comprise means (3, 13, 16, 17) for setting the maximum value of the power consumption of the peripheral device (2) to a value between said first maximum value and second maximum value.

10. The system of claim 9, wherein: comprising means (7, 10) for transmitting a message between the electronic device (1) and the peripheral device (2) for setting the power consumption of the peripheral device to a value substantially between said first maximum limit value and said second maximum limit value.

11. The system according to claim 9 or 10, characterized in that: the peripheral device (2) comprises means (16) for generating at least one clock signal, and the system comprises means (7, 10, 13) for controlling the power consumption of the peripheral device (2) by adjusting the frequency of said at least one clock signal.

12. The system of claim 9, 10 or 11, wherein: the peripheral device (2) comprises at least one bus and the system comprises means (7, 10, 13) for controlling the power consumption of the peripheral device (2) by adjusting the bus width of the peripheral device (2).

13. The system according to any one of claims 9 to 12, wherein: the peripheral device (2) has two or more memory blocks (14a-14d) and the means (7, 10, 13) for controlling the power consumption of the peripheral device (2) comprises means (13, 18a-18d) for adjusting the number of memory blocks (14a-14d) processed by the peripheral device (2) substantially simultaneously.

14. The system according to any one of claims 9 to 13, wherein: the electronic device (1) is a portable electronic device (1).

15. The system of claim 14, wherein: it comprises means (6) for performing the functions of the mobile station.

16. An electronic device (1) having means for connecting a peripheral device (2) and means (8) for supplying power to the peripheral device (2), and means (7) for determining power consumption, characterized in that: at least a first maximum value and a second maximum value higher than the first maximum value are defined for the power consumption, and the means for determining the power consumption comprise means (3) for setting the maximum value of the power consumption of the peripheral device (2) to a value between said first maximum value and said second maximum value.

17. The electronic device (1) according to claim 16, characterized in that: it comprises means (7) for sending messages to the peripheral device (2) and for receiving messages from the peripheral device (2) in order to set the power consumption of the peripheral device to a value substantially between said first maximum limit value and said second maximum limit value.

18. Electronic device (1) according to claim 16 or 17, characterized in that: it is a portable electronic device (1).

19. The electronic device (1) according to claim 18, characterized in that: it includes means for performing mobile station functions.

20. A peripheral device (2) having means (10) for connecting the peripheral device (2) to an electronic device (1), the power required for using the peripheral device (2) being arranged to be supplied from the electronic device (1) to the peripheral device (2), characterized in that: at least a first maximum value and a second maximum value higher than the first maximum value are defined for the power consumption, and the peripheral device comprises means (13, 16, 17) for setting the maximum value of the power consumption of the peripheral device (2) to a value between said first maximum value and said second maximum value.

21. The peripheral device (2) according to claim 20, wherein: at least one content is stored in the peripheral device (2) for use with the electronic device (1).

22. The peripheral device (2) according to claim 20 or 21, characterized in that: the peripheral device (2) comprises means (16) for generating at least one clock signal, and means (13) for controlling the power consumption of the peripheral device (2) by controlling the frequency of said at least one clock signal.

23. A peripheral device (2) according to claim 20, 21 or 22, characterized in that: the peripheral device (2) comprises at least one bus and means (13) for controlling the power consumption of the peripheral device (2) by controlling the bus width of the peripheral device (2).

24. The peripheral device (2) according to any one of claims 20 to 23, wherein: the peripheral device (2) has two or more memory blocks (14a-14d) and the means (7, 10, 13) for controlling the power consumption of the peripheral device (2) comprises means (13, 18a-18d) for controlling the number of memory blocks (14a-14d) processed by the peripheral device (2) substantially simultaneously.

25. The peripheral device (2) according to any one of claims 20 to 24, wherein: storing the first maximum value and the second maximum value in a peripheral device.

26. The peripheral device (2) according to any one of claims 20 to 25, wherein: it is a MultiMediaCard^TMA peripheral device.