CN201032745Y - Smart card of implementing inside power supply management - Google Patents

Smart card of implementing inside power supply management Download PDF

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Publication number
CN201032745Y
CN201032745Y CNU2007201035427U CN200720103542U CN201032745Y CN 201032745 Y CN201032745 Y CN 201032745Y CN U2007201035427 U CNU2007201035427 U CN U2007201035427U CN 200720103542 U CN200720103542 U CN 200720103542U CN 201032745 Y CN201032745 Y CN 201032745Y
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China
Prior art keywords
smart card
card
power management
power
power supply
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Expired - Fee Related
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CNU2007201035427U
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Chinese (zh)
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王鹿童
詹志勇
支军
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POENIX MCROELECTRONIC (CHINA) CO Ltd
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POENIX MCROELECTRONIC (CHINA) CO Ltd
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Abstract

The utility model relates to a smart card of managing power supply in the inside of a card which belongs to the technology field of a design of integrated circuit chip or a smart card. The smart card comprises a core chip set loaded on the printed circuit board and the peripheral power utilization unit, a power management unit is arranged in the smart card, the input terminal of the power management unit is connected with the power which is on the outside of the card through the power contact points of the smart card, the output terminal is connected with the inside core chip set of the smart card and the power supply pin of the peripheral power utilization component. The utility model ensures that the smart card is able to be utilized directly with the terminal system which meets the ISO7816-3 standard, but not need the terminal equipment to judge and to identify the working volt of the smart card; at the same time, the smart card is able to provide working volt of multiple (or single) same (or different) magnitude of voltage (or load) for the inside power utilization component.

Description

A kind of smart card of realizing power management in inside
Technical field
The utility model belongs to integrated circuit (IC) chip/smart card designs technical field, and is particularly a kind of at the inner smart card that carries out power management of card.
Background technology
1970, Frenchman rowland De Moruinuo (Roland Moreno) IC (Integrated Circuit) chip that is provided with of can programming for the first time was put in the card, makes card have more function.He had done following elaboration to this invention in application for patent at that time: have the memory that can carry out self-protection on the card.First intellective IC card in the world so just has been born.
For the integrated circuit smart card, general definition is: be made up of one or more integrated circuit (IC) chip, and be packaged into and be convenient to the card that people carry; Have temporary transient or nonvolatil data storage capacities, its content can read or supply inter-process, judgement for the outside; Have logic and mathematical operation disposal ability, be used to discern the information that provides with response external and the processing demands of chip itself.
The smart card that we use always roughly divides four kinds: storage card, encryption storage card, CPU card, radio-frequency card.With the digital cellular telephone is example, be to use the CPU card to come stored information and unique identification user identity, the smart card of this particular type often is called as SIM (Subscriber Identity Module, subscriber identification module) card, provide the ability of big capacity storage, telephone directory book can exist card to go up rather than exist on the mobile phone just because of smart card as analog telephone.The fail safe that microprocessor in blocking has in addition improved user account number greatly.
Continuous innovation along with Development of Multimedia Technology and consumer electronics technology, portable electronic product has become the personal entertainment center gradually, increasing audio frequency, video, image, recreation have proposed complicated data processing demand, and have promoted the disposal ability of CPU significantly to improve.Smart card also has been endowed the more data processing capacity under such background, and the core processor dominant frequency of CPU type smart card is more and more higher, and operating voltage also has been upgraded to applicable to any special chip at this application.Initial IS07816-3 and EMV (Europay/Master card/Visa) file comprises that now 1.8V, 3.0V and 5.0V are as the working power that is suitable for.Therefore, the physical interface between card and microcontroller is necessary can be adaptive with the main PMU of above-mentioned any power supply and terminal equipment.
According to ISO/IEC 7816-2 standard, the electrical characteristics of smart card VCC contact are as shown in table 1 under the normal operating condition.
Day by day extensive along with what use, to the telstar receiver, intelligent card interface must be handled big input voltage range and have high efficiency from battery powered portable system.For mobile phone,, facilitated the transformation that cell voltage is changed into 3V from 6V or 4.5V energetically in order to respond the pressure that market demands alleviate weight of equipment.Because the component of all mobile phones all can use 3V at present, so mobile phone needs a voltage changer to provide the 5V card the required energy, this has just increased complexity, and unnecessary cost.Therefore, it is 3V to 5V that present development causes the smart card voltage range, positive and negative 10%, and its effective voltage scope is between 2.7V to 5.5V.Can only be by the demand of terminal equipment according to different cards, automatically selected required 3V of card or the 5V supply voltage of offering.A kind of possible solution as shown in Figure 1.
The electrical characteristics of smart card VCC contact under table 1 normal operating condition
Symbol Condition Minimum value Maximum Unit
Vcc The category-A category-B 4.5 2.7 5.5 3.3 V
Icc Category-A at maximum tolerance frequency category-B, stops at maximum tolerance frequency clock 60 5 0 0.5 mA
In fact, for the smart card terminal equipment of lithium electricity power supply, used the card controller integrated circuit of 3V, from the angle of terminal, its challenge of facing is:
The first, as select the terminal equipment that is merely able to support the 3V smart card for use, then mean the compatibility that has lost millions of existing 5V smart cards.
The second, if select the terminal equipment of only supporting the 5V smart card for use, when the 3V smart card inserts this equipment, will be very likely destroyed then.Therefore the user must select terminal carefully, avoids damaging because of misoperation smart card.
The 3rd, because the innovation and the demands of applications of technology, the smart card that has caused different operating voltage is for the simple compatibility of terminal equipment.General 3V smart card (sim card) on the cell phone apparatus particularly can not be directly connected to such as PC computer etc. and only support on the terminal equipment of 5V power supply, must pass through interconnecting device and could realize and being connected of this kind equipment.
Usually, because bench device adopts the fixed power source power supply, so almost whole desk-top smart card terminal equipment all is the equipment of only supporting the 5V power supply; And owing to portable or handheld-type intelligent card terminal equipment adopt lithium battery as power supply, therefore, handheld devices such as most of mobile phone all are only to support the terminal equipment of 3V smart card.Along with the memory function of smart card is become stronger day by day, the user tends to the medium of smart card as storage and exchange, and with its frequent alternately being connected between handheld device and bench device.For operating voltage is the smart card of 3V, connects only to support the equipment of 5V power supply to finish by interconnecting device.From user's angle,,, will improve the compatibility and the fail safe of smart card so greatly as typical 1.8V, 3V and 5V if smartcard internal can support that the multiplex (MUX) makes voltage.
From the angle of smartcard internal, also produced new problem:
The first, the contradiction of function and power consumption manifests gradually.The function of smart card is become stronger day by day, its power consumption increases sharply thereupon, load current has substantially exceeded the rank of early stage smart card, along with smart card inner core performance of processors promotes, and the load current that complicated a large amount of computings produce even reached up to a hundred milliamperes magnitude.
The second, because the application of new application, particularly multimedia and big capacity storage makes the arithmetic speed of smartcard internal integrated circuit improve constantly, the bus frequency of advanced CPU card has reached the rank of tens megahertzes at present.Under high-frequency like this, the power supply noise of chip internal has produced influence to the signal integrity of circuit, must take measures in smartcard internal, noise is controlled, to improve the signal quality of smartcard internal.Simultaneously, the appearance of noise has also produced influence to power quality, if do not handle targetedly in smartcard internal, its inside can not obtain high-quality power supply with electric device, operating state also will descend.
The 3rd, because the continuous increase of smartcard internal integrate circuit function, particularly handheld terminal equipment is to the demand of big capacity storage performance, the smart card product that inner encapsulation polylith integrated circuit (IC) chip occurred, how provide adaptive power supply with electric device, become a new problem for each of smartcard internal.With typical memory element NAND Flash is example, according to the difference of capacity, have the device of multiple operating voltages such as 1.8V, 3V, 5V in the market, this just requires, when smart card is encapsulated in card body inside to jumbo memory component, is necessary for it satisfactory working power is provided.And when other of encapsulation in the card are inequality with the operating voltage of electric device and NAND Flash operating voltage, use the power management scheme outside blocking to be difficult to solve this difficult problem.
The 4th, the progress of semiconductor fabrication process has increased electric power management circuit and main logical circuit has been integrated in difficulty on the chip piece.On the one hand, can be integrated in the Power Management Unit of chip internal, because efficient is on the low side, load capacity is less, can not be adapted to the requirement of multicore sheet power supply in the smart card.On the other hand, the main flow that the processing technology of deep-submicron even Nano grade becomes logical circuit realizes technology, and high performance electric power management circuit also is difficult to realize on such technology.
According to the above, new application requirements smart card can bear the outside 2.7V that supplies with to the 5.5V power supply, and provides multiplex operation voltages such as 1.8V, 3V and 5V simultaneously in card inside; And this management to power supply is not rely on exterior terminal equipment, but realize in smartcard internal.But, want to realize on the logic chip in smart card that power management is very difficult, must seek new solution, realize the power management of smartcard internal.
Summary of the invention
The purpose of this utility model is to provide a kind of can bear the voltage that outside different electrical power is supplied with at the inner smart card that carries out power management of card, and can provide multiplex operation voltage with electric device for the acp chip group and the periphery of inside.
In order to realize above-mentioned utility model purpose, technical scheme provided by the utility model is as follows:
A kind of smart card of realizing power management in inside, comprise acp chip group by the printed circuit board (PCB) carrying, also be provided with Power Management Unit in smartcard internal, the outer power supply of the power contact of the input of Power Management Unit by smart card and card is connected, and output and smartcard internal acp chip group and peripheral power pins with electric device are connected.
Further, more than said smart card comprise UIM (User Identity Model in SIM card in the gsm system, the cdma system, subscriber identification module) PIM (PersonalIdentity Module, personal identifier module) card in card, the PHS system and USIM (the UniversalSubscriber Identity Module) card in the 3G system.
Furthermore, the aforesaid smart card of realizing power management in inside, wherein, Power Management Unit is a kind of in the middle of linear voltage regulator LDO, DC-DC transducer or the boosting charge pump.
The aforesaid smart card of realizing power management in inside wherein, also is provided with the core circuit periphery components and parts that are connected, play the protective circuit effect with the pin of related chip on the printed circuit board (PCB).These core circuit periphery components and parts can be electric capacity, inductance, resistance.
The aforesaid smart card of realizing power management in inside, wherein, Power Management Unit, acp chip group, printed circuit board (PCB) and core circuit periphery components and parts pass through the contact SIM card packing forms overall package of 8 hard contacts in smart card.
Further, described acp chip group comprises: primary processor CPU, multimedia messages coprocessor, high-speed interface controller, the memory device controller, SIM controller, read-only memory (ROM), static memory (SRAM), flash memory (FLASH), hardware accelerator.
The beneficial effects of the utility model are: by the smart card of realizing power management in inside provided by the utility model, can the power source conversion that card is outer become card inner core chipset and peripheral working power with electric device; Make smart card directly be connected use, and do not need terminal equipment that the operating voltage of smart card is judged identification with the terminal equipment that satisfies the ISO7816-3 standard; Simultaneously; this smart card can be inner acp chip group and the peripheral working power that different (or identical) magnitudes of voltage of multichannel (or a tunnel) (or load value) are provided with electric device; when smart card and forward are above standard the terminal equipment of power range when being connected; the protection smart card is not burnt; when smart card and negative sense are above standard the terminal equipment of power range when being connected, keep the operate as normal of smart card.
Description of drawings
Fig. 1 is the state diagram selected of terminal equipment transaction card supply voltage (a description status machine how the required minimum operating voltage of selection card).
Fig. 2 realizes the smart card architecture schematic diagram of power management in smartcard internal.
Fig. 3 is the structural representation of power management module PMU among the embodiment described in the utility model.
Fig. 4 realizes the circuit diagram of power management for smartcard internal adopts linear voltage regulator (LDO).
Embodiment
Below in conjunction with drawings and Examples the utility model is described in further detail.
As shown in Figure 2, be example with the SIM card, realize smart card 1 specifically composed as follows of power management in inside:
Power Management Unit 2: in smart card 1 inside, the outer power supply of the power contact of its input by smart card and card is connected, and output and smart card 1 internal core chipset and peripheral power pins with electric device are connected.Power Management Unit 2 should become the power source conversion of smart card 1 outside card internal core chipset and the periphery required power supply of electric device 3 work.
Acp chip group and periphery electric device 3: in smartcard internal, comprise primary processor CPU, the multimedia messages coprocessor, the high-speed interface controller, memory device controller, SIM controller, read-only memory (ROM), static memory (SRAM), flash memory (FLASH), other hardware accelerators etc.The acp chip group should be finished the communication function and the information processing function of SIM card, can be made up of chip piece or polylith chip.The acp chip group provides working power by Power Management Unit, and the power supply with the smart card outside directly is not connected.The periphery components and parts are the core circuit peripheral elements that comprise electric capacity, inductance, resistance etc.Can play the effect of protective circuit, be placed in equally on the printed circuit board (PCB), be connected with the pin of related chip, and be encapsulated in smartcard internal.
Printed circuit board (PCB) (PCB): as the supporting body of polylith chip in the smart card, the smart card that the utility model proposed should comprise a slim printed circuit board (PCB) (PCB), this pcb board should have certain intensity, and thickness can satisfy and is encapsulated in SIM card inside.This pcb board should have suitable wiring, in conjunction with the position that is placed in the polylith chip on the pcb board, needs interconnected pin to connect by printed wire these chips.
Packing forms: the outward appearance of the smart card that the utility model proposed, meet the relevant regulations of ISO/IEC 7816-1 standard, adopt the contact SIM card packing forms of 8 hard contacts.The smart card that 8 hard contacts can support the utility model to propose is connected with terminal equipment.
From smart card external power source environment angle analysis, smart card adopts lithium battery power supply on handheld device, generally is the D.C. regulated power supply power supply on bench device, so the outer power voltage scope of smart card is between the 2.7V to 5.5V.
From smartcard internal acp chip group and peripheral operating voltage analysis with electric device, with the most complicated SOC (SOC (system on a chip)) level chip is example, the circuit voltage of its CPU and master controller part is 2.5V, and the operating voltage of memory circuitry can be 3V or 1.8V.
More than 2 require the power management device in the smart card can pass through power source conversion, be the internal core chipset and peripherally power from external power source with electric device.Simultaneously, because will realize power management, therefore must selection can go up the scheme that realizes at silicon nude film (DIE) in smartcard internal.When just requiring work, this can not have due to voltage spikes can realize again simultaneously accurately adjusting and low ripple.The most important thing is that circuit must satisfy all EMV standards, especially power supply decreasing sequence, power remove sequential and output short circuit current.
Through type selecting, there are 3 class power management devices can satisfy above-mentioned requirements: linear voltage regulator (LDO), DC-DC transducer and boosting charge pump (CHARGE PUMP).Wherein:
The noise of linear voltage regulator (LDO) input and output is very little, circuit is simple and easy to realize relatively, but only has the translation function that reduces voltage, only be lower than under the situation of smart card external power source suitable with the operating voltage of electric device at acp chip group and periphery, and along with the increase of input and output voltage difference, conversion efficiency will reduce gradually;
The DC-DC transducer can raise and reduce the operation of voltage, be commonly used in the mobile communication terminal device smart card (SIM card) is carried out power management, under the call mode of mobile phone, have usually and be higher than 90% high efficiency, but the peripheral connection inductance component that needs, therefore output noise is very big, and circuit is complicated;
The function of charge pump (CHARGE PUMP) is similar to the DC-DC transducer, but the periphery does not need to connect inductance, and output noise is little than DC-DC, but efficient is not high usually, only is about 60%.
Present embodiment is an example with the scheme that adopts linear voltage regulator (LDO), has proposed a kind of smart card that can carry out power management in inside.
The pin function (being output as example) of table 2. smartcard internal multiple-output electric power administrative unit with two-way
The pin sequence number The pin title Pin function is described
1 VIN The power supply input
2 GND Ground
3 EN2 LDO2 enables input, and logic high is for opening, and logic low is for closing
4 EN1 LDO1 enables input, and logic high is for opening, and logic low is for closing
5 VOUT2 The output of LDO2 voltage
6 VOUT1 The output of LDO1 voltage
At first according to Fig. 3, Fig. 4, the applied environment of the utility model is to have the smart card system of two semiconductors with electric device.
Wherein, PMU (U1) is the Power Management Unit of smartcard internal, connects smart card externally fed equipment, for the semiconductor of smartcard internal provides adaptive power supply with electric device; and protect smartcard internal not burnt by electricity with electric device, its structure is as shown in Figure 3.
CONTROLER (U2) is the control chip of smartcard internal, it is other large-scale semiconductive integrated circuit of SOC (system on a chip) (SOC) level, comprise primary processor, multimedia messages coprocessor, high-speed interface controller, the memory device controller, the SIM controller, read-only memory (ROM), static memory (SRAM), flash memory (FLASH), core logic circuits such as other hardware accelerators.Need 3.0V during operate as normal, positive and negative 10% operating voltage.
NAND_FLASH_X8 (U3) is the smartcard internal memory cell, is semiconductor element, can be integrated in on the chip piece with CONTROLER, and also can adopting independently, silicon nude film (DIE) is encapsulated in the smart card with the CONTROLER chip.Need 1.8V during operate as normal, positive and negative 10% operating voltage.
Capacitor C 1, C2, C3 are filtering devices, are connected on the input and output side of PMU (U1), carry out filtering to improve the quality of output voltage at input, output.
For guaranteeing the smart card operate as normal, build circuit according to following description:
The input (VIN) of PMU (U1) is linked to each other with smart card standard contact C1, and ground (GND) links to each other with smart card standard contact C5, and connects the power-supply device of smart card outside by smart card contact;
The enable signal end (EN1/EN2) of PMU (U1) is connected with VIN, so that the output of the two-way of PMU effectively;
The output one (OUT1) of PMU (U1) is connected with the VDD of NAND_FLASH_X8 (U3), the VSS of NAND_FLASH_X8 (U3) is linked to each other with smart card standard contact C5, and provide working power for NAND_FLASH_X8 (U3) by the output one (OUT1) of PMU;
The output two (OUT2) of PMU (U1) is connected with the VDD of CONTROLLER (U2), and the VSS of CONTROLLER (U2) is linked to each other with smart card standard contact C5, and provide working power for CONTROLLER (U2) by the output two (OUT2) of PMU;
The circuit that to build according to above-mentioned connected mode is encapsulated into the smart card with 8 hard contacts, and outward appearance satisfies the relevant regulations of ISO 7816-1, and SIM card seat that can be by the insertion standard is by terminal equipment identification and operate as normal.Simultaneously, built-in Power Management Unit can be to the chip power supply in the SIM card, and the operating voltage of 1.8V and 3V can be provided respectively.
The smart card external power supply can not directly be connected with electric device with smartcard internal as mentioned above, but powers with electric device for smartcard internal by smartcard internal Power Management Unit PMU (U1).When the smart card external voltage in that 2.7V~5.5V is interval when changing, can be powering of smartcard internal by PMU (U1) with electric device; Exceed in the PMU load in limited time when external voltage exceeds critical field or load current, PMU (U1) will turn-off, and protection smartcard internal acp chip group and peripherally do not burnt by electricity with electric device.
Consider disclosed hereinly to description of the present utility model and special embodiment, other embodiment of the present utility model are conspicuous for a person skilled in the art.These explanations and embodiment only consider as an example that they all belong to by within the indicated protection range of the present utility model and spirit of claims.

Claims (7)

1. smart card of realizing power management in inside, comprise acp chip group by the printed circuit board (PCB) carrying, it is characterized in that: also be provided with Power Management Unit in smartcard internal, the outer power supply of the power contact of the input of described Power Management Unit by smart card and card is connected, and output and smartcard internal acp chip group and peripheral power pins with electric device are connected.
2. the smart card of realizing power management in inside according to claim 1 is characterized in that: described smart card comprises in SIM card in the gsm system, the cdma system PIM card in UIM card, the PHS system and the usim card in the 3G system.
3. the smart card of realizing power management in inside according to claim 1 and 2 is characterized in that: described Power Management Unit is a kind of in the middle of linear voltage regulator LD0, DC-DC transducer or the boosting charge pump.
4. the smart card of realizing power management in inside according to claim 1 and 2 is characterized in that: also be provided with the core circuit periphery components and parts that are connected, play the protective circuit effect with the pin of related chip on the described printed circuit board (PCB).
5. the smart card of realizing power management in inside according to claim 4 is characterized in that: described core circuit periphery components and parts comprise electric capacity, inductance, the resistance that is connected with the related chip pin.
6. the smart card of realizing power management in inside according to claim 5 is characterized in that: Power Management Unit, acp chip group, printed circuit board (PCB) and core circuit periphery components and parts pass through the contact SIM card packing forms overall package of 8 hard contacts in smart card.
7. the smart card of realizing power management in inside according to claim 6, it is characterized in that described acp chip group comprises: primary processor CPU, the multimedia messages coprocessor, the high-speed interface controller, memory device controller, SIM controller, read-only memory, static memory, flash memory, hardware accelerator.
CNU2007201035427U 2007-02-09 2007-02-09 Smart card of implementing inside power supply management Expired - Fee Related CN201032745Y (en)

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN104519565A (en) * 2013-10-08 2015-04-15 北京旅信顺捷软件科技有限公司 Thin-film SIM (subscriber identity module) card and SIM card switching method based on thin-film SIM card

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN104519565A (en) * 2013-10-08 2015-04-15 北京旅信顺捷软件科技有限公司 Thin-film SIM (subscriber identity module) card and SIM card switching method based on thin-film SIM card

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Granted publication date: 20080305