CN103531233A - Power-fail protective circuit and power-fail protective sequential circuit for flash memory - Google Patents
Power-fail protective circuit and power-fail protective sequential circuit for flash memory Download PDFInfo
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- CN103531233A CN103531233A CN201210226126.1A CN201210226126A CN103531233A CN 103531233 A CN103531233 A CN 103531233A CN 201210226126 A CN201210226126 A CN 201210226126A CN 103531233 A CN103531233 A CN 103531233A
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Abstract
The invention relates to a power-fail protective sequential circuit for a flash memory. The power-fail protective sequential circuit comprises an independent power supply converting module, a power supply monitoring module, a write-protection module and a reset module, wherein the independent power supply converting module is used for converting an exterior power supply into an internal power supply which is output through the output end of the independent power supply converting module, and thus the internal power supply power-fail at last is realized during the process of the exterior power supply power-fail; the power supply monitoring module is used for obtaining the exterior power supply, and outputting an alarm signal when the voltage of the exterior power supply is less than a power-fail threshold. The invention further relates to a power-fail protective circuit for the flash memory. The power-fail protective circuit is used for pulling the write-protection pin of the flash memory to a low level when the voltage of the exterior power supply decreases to be less than the power-fail threshold, the flash memory is put at a write-protection state until power-fail is finished. So that, during the power-fail process, data stored in the flash memory can not be erased, the safety of the stored data is improved.
Description
Technical field
The present invention relates to emergency protection circuit device for electric, particularly relate to a kind of power-down protection circuit for flash memory, also relate to a kind of power down protection sequential circuit for flash memory.
Background technology
The English name of flash memory is " Flash Memory ", generally referred to as " Flash ".Flash memory is a kind of non-volatile (Non-Volatile) storer, under the condition that there is no electric current supply, also can keep muchly data, its storage characteristics is equivalent to hard disk, and this characteristic just flash memory is become the basis of the storage medium of all kinds of pocket digital devices.Flash memory is mainly divided into NOR type and the large class of NAND type two.
The storage unit of nand flash memory adopts serial structure, and the read-write Shi Yi Ye Hekuaiwei unit of storage unit carries out (one page comprises some bytes, and some pages form block storage, and the storage block size of NAND is 8 to 32KB).The advantage of this structure maximum is that capacity can do very greatly, and the NAND product that surpasses 512MB capacity is quite general, and the cost of nand flash memory is lower, is conducive to extensive universal.
The feature of NOR flash memory is in chip, to carry out (XIP, eXecute In Place), and application program can directly be moved in NOR flash memory like this, needn't code be read in system RAM again.The transfer efficiency of NOR is very high, has very high cost benefit when the low capacity of 1～4MB, but very low writing affected its performance greatly with erasing speed.
Flash memory is nonvolatile memory, can carry out erasable and programme being called the memory cell block of piece.The write operation of any fash device can only be carried out in unit empty or that wiped, so in most cases, before carrying out write operation, must first carry out and wipe.It is foolproof that NAND device is carried out erase operation, and NOR requires first positions all in object block to be all written as to 0 before wiping.
In actual applications, in power down process, because state is uncontrollable, there is the possibility of maloperation in the central processing unit of partially embedded product, the content of partial block in flash memory can be wiped by mistake, causes product cannot again start after power-off.
Summary of the invention
Based on this, being necessary, for traditional flash memory problem that easily data are wiped in power down process by mistake, provides a kind of power-down protection circuit for flash memory.
For a power-down protection circuit for flash memory, comprise Power Monitoring Unit and electronic switch unit, described Power Monitoring Unit connecting electronic switch element, described electronic switch unit is for connecting the write-protect pin of flash memory; Described Power Monitoring Unit is used for obtaining externally fed power supply, and when the voltage of described externally fed power supply is less than power down threshold value, controls described electronic switch unit output low level to described write-protect pin; Described electronic switch unit comprises the first divider resistance, the second divider resistance, pull down resistor and the first switching tube, described the first switching tube comprises input end, output terminal and control end, the output terminal of described the first switching tube is used for connecting described write-protect pin, and the output terminal of described the first switching tube is by described pull down resistor ground connection; The input end of described the first switching tube is for connecting the power supply of described flash memory, and the input end of described the first switching tube connects the control end of described the first switching tube by described the second divider resistance; The control end of described the first switching tube connects described Power Monitoring Unit by described the first divider resistance.
Therein in an embodiment, described the first switching tube is positive-negative-positive triode, the input end of described the first switching tube is the emitter of described triode, the collector that the output terminal of described the first switching tube is described triode, the base stage that the control end of described the first switching tube is described triode.
Therein in an embodiment, described Power Monitoring Unit comprises second switch pipe, the 3rd divider resistance, the 4th divider resistance and the 5th divider resistance, described second switch pipe comprises input end, output terminal and control end, and the input end of described second switch pipe connects described externally fed power supply by described the 3rd divider resistance; The output head grounding of described second switch pipe; The control end of described second switch pipe connects described externally fed power supply by described the 4th divider resistance, and the control end of described second switch pipe is by described the 5th divider resistance ground connection.
Therein in an embodiment, described second switch pipe is NPN type triode, the input end of described second switch pipe is the collector of described NPN type triode, the output terminal of described second switch pipe is the emitter of described NPN type triode, and the control end of described second switch pipe is the base stage of described NPN type triode; Described Power Monitoring Unit also comprises in parallel for adjusting the electric capacity of sequential with described the 5th divider resistance.
Above-mentioned power-down protection circuit; when the voltage of externally fed power supply drops to power down threshold value when following (now the required Ge of central processing unit road supply voltage is also within rated range); Power Monitoring Unit is exported high level and by the first divider resistance, is delivered to the control end of the first switching tube; make the first switching tube cut-off; the write-protect pin of flash memory is pulled to low level by pull down resistor; flash memory is placed in write-protect state, until power down finishes.Therefore, in power down process, the data of storing in flash memory can not be wiped free of, and have improved the security of the data of storage.
Also be necessary to provide a kind of power down protection sequential circuit for flash memory.
A power down protection sequential circuit for flash memory, comprises independent current source modular converter, Power Monitoring Unit, write-protect module and reseting module; Described independent current source modular converter is used for externally fed power supply being converted to internal power supply and exporting by the output terminal of independent current source modular converter, thereby realizes the last power down of internal power supply in described externally fed power supply power-fail process; Described Power Monitoring Unit is used for obtaining externally fed power supply, and when the voltage of described externally fed power supply is less than power down threshold value outputting alarm signal; Described write-protect module comprises trigger element and electronic switch unit; Described trigger element is connected with output terminal, Power Monitoring Unit and the electronic switch unit of described independent current source modular converter, described electronic switch unit is for connecting the write-protect pin of flash memory, and described trigger element triggers described electronic switch unit output low level to described write-protect pin under the alarm signal of described Power Monitoring Unit is controlled; Described reseting module is connected with Power Monitoring Unit with the output terminal of described independent current source modular converter, for export reset signal when receiving described alarm signal; Described electronic switch unit comprises the first divider resistance, the second divider resistance, pull down resistor and the first switching tube, described the first switching tube comprises input end, output terminal and control end, the output terminal of described the first switching tube is used for connecting described write-protect pin, and the output terminal of described the first switching tube is by described pull down resistor ground connection; The input end of described the first switching tube is for connecting the output terminal of described independent current source modular converter, and the input end of described the first switching tube connects the control end of described the first switching tube by described the second divider resistance, the control end of described the first switching tube connects trigger element by described the first divider resistance.
Therein in an embodiment, described independent current source modular converter comprises the 3rd divider resistance, stabilivolt and second switch pipe, described second switch pipe comprises input end, output terminal and control end, the input end of described second switch pipe is used for connecting described externally fed power supply, between the input end of described second switch pipe and control end, be connected to described the 3rd divider resistance, the output terminal of described independent current source modular converter is the output terminal of described second switch pipe, described the 3rd divider resistance connects one end of the control end of described second switch pipe and passes through described stabilivolt ground connection, one end of described stabilivolt ground connection is the anode of stabilivolt.
In an embodiment, described Power Monitoring Unit comprises microprocessor reset chip, the 4th divider resistance, the 5th divider resistance, the first pull-up resistor, the first current-limiting resistance and the first delay capacitor therein; The power supply input pin of described microprocessor reset chip connects described externally fed power supply by described the 4th divider resistance, and described power supply input pin is by described the 5th divider resistance ground connection, and described the first delay capacitor is in parallel with described the 5th divider resistance; The lower margin ground connection of described microprocessor reset chip; The reset pin of described microprocessor reset chip is used for exporting described alarm signal; Described reset pin connects the output terminal of described independent current source modular converter by described pull-up resistor, described reset pin connects the interrupt pin of central processing unit by described the first current-limiting resistance.
In an embodiment, described trigger element comprises the first time delay resistance, the second pull-up resistor, the second delay capacitor and the 3rd switching tube therein, and described the 3rd switching tube comprises input end, output terminal and control end; The input end of described the 3rd switching tube connects the output terminal of described independent current source modular converter by described the second pull-up resistor, the input end of described the 3rd switching tube also connects described electronic switch unit by described the first divider resistance; The output head grounding of described the 3rd switching tube; The control end of described the 3rd switching tube passes through described the second delay capacitor ground connection, and connects described Power Monitoring Unit to obtain described alarm signal by described the first time delay resistance.
In an embodiment, described electronic switch unit also comprises the second current-limiting resistance of being located between the output terminal of described the first switching tube and the write-protect pin of described flash memory therein.
In an embodiment, described reseting module comprises the second time delay resistance, the 3rd pull-up resistor, the 3rd delay capacitor, filter capacitor and the 4th switching tube therein; Described the 4th switching tube comprises input end, output terminal and control end; The input end of described the 4th switching tube connects the output terminal of described independent current source modular converter by described the 3rd pull-up resistor; The output head grounding of described the 4th switching tube, the control end of described the 4th switching tube passes through described the 3rd delay capacitor ground connection, and connects described Power Monitoring Unit to obtain described alarm signal by described the second time delay resistance; Described the 3rd pull-up resistor connects one end of described filter capacitor for exporting described reset signal.
Above-mentioned power down protection sequential circuit; when the voltage of externally fed power supply drops to power down threshold value when following (now the required Ge of central processing unit road supply voltage is also within rated range); Power Monitoring Unit outputting alarm signal; make the control end of trigger element output high level to the first switching tube; make the first switching tube cut-off; the write-protect pin of flash memory is pulled to low level by pull down resistor, and flash memory is placed in write-protect state, until power down finishes.Therefore, in power down process, the data of storing in flash memory can not be wiped free of, and have improved the security of the data of storage.
Accompanying drawing explanation
Fig. 1 is for the circuit theory diagrams of the power-down protection circuit of flash memory in an embodiment;
Fig. 2 is for the circuit structure diagram of the power down protection sequential circuit of flash memory in an embodiment;
Fig. 3 be in an embodiment for the power down protection sequential circuit of flash memory the circuit theory diagrams of the circuit except independent current source modular converter;
Fig. 4 is the circuit theory diagrams of independent current source modular converter in an embodiment.
Embodiment
For object of the present invention, feature and advantage can more be become apparent, below in conjunction with accompanying drawing, the specific embodiment of the present invention is described in detail.
Fig. 1 is for the circuit theory diagrams of the power-down protection circuit of flash memory in an embodiment.Power-down protection circuit 100 comprises Power Monitoring Unit 110 and electronic switch unit 120, Power Monitoring Unit 110 connecting electronic switch elements 120, and electronic switch unit 120 is for connecting the write-protect pin of flash memory (Flash).Power Monitoring Unit 100 is for obtaining externally fed power supply (VDD), and (now the voltage of central processing unit is also within rated range) controls electronic switch unit 120 output low levels to the write-protect pin of flash memory when externally the voltage of power supply is less than power down threshold value.
In the embodiment shown in fig. 1, the first switching tube Q2 is positive-negative-positive triode, the emitter that the input end of the first switching tube Q2 is triode, the collector that the output terminal of the first switching tube Q2 is triode, the base stage that the control end of the first switching tube Q2 is triode.In other embodiments, the first switching tube Q2 also can adopt other suitable switching device of response time, for example P channel mosfet.
When the voltage of externally fed power supply drops to power down threshold value when following (now the required Ge of central processing unit road supply voltage is also within rated range); Power Monitoring Unit 110 is exported high level and by the first divider resistance R5, is delivered to the control end of the first switching tube Q2; make the first switching tube Q2 cut-off; the write-protect pin of flash memory is pulled to low level by pull down resistor R7; flash memory is placed in write-protect state, until power down finishes.Therefore, in power down process, the data of storing in flash memory can not be wiped free of, and have improved the security of the data of storage.This power-down protection circuit 100 is simple and practical, with low cost.
In the embodiment shown in fig. 1, Power Monitoring Unit 110 comprises second switch pipe Q1, the 3rd divider resistance R3, the 4th divider resistance R1 and the 5th divider resistance R2.Second switch pipe Q1 comprises input end, output terminal and control end, and the input end of second switch pipe Q1 connects externally fed power supply (VDD) by the 3rd divider resistance R3; The output head grounding of second switch pipe Q1; The control end of second switch pipe Q1 connects externally fed power supply by the 4th divider resistance R1, and the control end of second switch pipe Q1 is by the 5th divider resistance R2 ground connection.
In the embodiment shown in fig. 1, second switch pipe Q1 is NPN type triode, the collector that the input end of second switch pipe Q1 is triode, the emitter that the output terminal of second switch pipe Q1 is triode, the base stage that the control end of second switch pipe Q1 is triode.In other embodiments, second switch pipe Q1 also can adopt other suitable switching device of response time, for example N-channel MOS FET.
In the embodiment shown in fig. 1, Power Monitoring Unit 110 also comprise in parallel with the 5th divider resistance R2, for adjusting the capacitor C 1 of sequential.The 4th divider resistance R1, the 5th divider resistance R2 and capacitor C 1 form delay unit.In the embodiment shown in fig. 1, electronic switch unit 120 also comprises the current-limiting resistance R8 being located between the collector of positive-negative-positive triode Q2 and the write-protect pin of flash memory.
According to the resistance of the specification of external power adapter (having determined the rated voltage of externally fed power supply) choose reasonable the 4th divider resistance R1 and the 5th divider resistance R2, just can set power down threshold value, make the accurate onset of Power Monitoring Unit 110, this power down threshold value is an empirical value.The value of the 3rd divider resistance R3 should provide suitable bias current to NPN type triode Q1, makes the accurate onset of triode; Same, the resistance of answering choose reasonable the first divider resistance R5 and pull down resistor R7, makes accurately onset of positive-negative-positive triode Q2.
The present invention also provides a kind of power down protection sequential circuit for flash memory, and Fig. 2 is for the circuit structure diagram of the power down protection sequential circuit of flash memory in an embodiment.Power down protection sequential circuit comprises Power Monitoring Unit 10, write-protect module 20, independent current source modular converter 30 and reseting module 40.Independent current source modular converter 30 is for being converted to externally fed power supply internal power supply (being the direct current of 3.3V in one embodiment), and export by the output terminal of independent current source modular converter 30, thereby externally in power supply power down process, realize the last power down of internal power supply.10 of Power Supply Monitoring moulds are for obtaining externally fed power supply, and outputting alarm signal when externally the voltage of power supply is less than power down threshold value.
Refer to Fig. 3, write-protect module 20 comprises trigger element 210 and electronic switch unit 220.Trigger element 210 is connected with electronic switch unit 220 with output terminal (i.e. the port of output+3.3V), the Power Monitoring Unit 10 of independent current source modular converter 30, and electronic switch unit 220 is for connecting the write-protect pin of flash memory.Trigger element 210, under the alarm signal of Power Monitoring Unit 10 is controlled, triggers electronic switch unit 220 output low levels to the write-protect pin of flash memory.
When the voltage of externally fed power supply drops to power down threshold value when following (now the required Ge of central processing unit road supply voltage is also within rated range); Power Monitoring Unit 10 outputting alarm signals; make the control end of trigger element 210 output high level to the first switching tube Q2; control the first switching tube Q2 cut-off; the write-protect pin of flash memory is pulled to low level by pull down resistor R9; flash memory is placed in write-protect state, until power down finishes.Therefore, in power down process, the data of storing in flash memory can not be wiped free of, and have improved the security of the data of storage.
In the embodiment shown in fig. 3, the first switching tube Q2 is positive-negative-positive triode, the emitter that the input end of the first switching tube Q2 is triode, the collector that the output terminal of the first switching tube Q2 is triode, the base stage that the control end of the first switching tube Q2 is triode.In other embodiments, the first switching tube Q2 also can adopt other suitable switching device of response time, for example P channel mosfet.In an embodiment, electronic switch unit 220 also comprises the second current-limiting resistance R16 being located between the collector of positive-negative-positive triode Q2 and the write-protect pin of flash memory therein.
In the embodiment shown in fig. 3, the 3rd switching tube Q1 is NPN type triode, the collector that the input end of the 3rd switching tube Q1 is triode, the emitter that the output terminal of the 3rd switching tube Q1 is triode, the base stage that the control end of the 3rd switching tube Q1 is triode.In other embodiments, the 3rd switching tube Q1 also can adopt other suitable switching device of response time, for example N-channel MOS FET.
In the embodiment shown in fig. 3, power down protection sequential circuit also comprises the reseting module 40 being connected with Power Monitoring Unit 10, and reseting module 40 for exporting reset signal when receiving alarm signal.Reseting module 40 comprises the second time delay resistance R10, the 3rd pull-up resistor R11, the 3rd delay capacitor C4, filter capacitor C5 and the 4th switching tube Q3, and the 4th switching tube Q3 comprises input end, output terminal and control end.The input end of the 4th switching tube Q3 connects the output terminal of independent current source modular converter 30 by the 3rd pull-up resistor R11, the input end of the 4th switching tube Q3 is also by filter capacitor C5 ground connection; The output head grounding of the 4th switching tube Q3; The control end of the 4th switching tube Q3 passes through the 3rd delay capacitor C4 ground connection, and connects Power Monitoring Unit 10 to obtain alarm signal by the second time delay resistance R10.One end that the 3rd pull-up resistor R11 connects filter capacitor C5 is used for exporting reset signal.Reset signal is divided two-way to export ，Yi road and is connected with the reset pin of NOR FLASH, and another road is connected with all reset pins of homing device that need except NOR FLASH in system.Because NAND FLASH does not exist reset pin, so only consider in the present embodiment to provide reset signal to NOR FLASH.The output of two-way reset signal can be connected respectively and be accessed a current-limiting resistance R12 and R13.
In the embodiment shown in fig. 3, the 4th switching tube Q3 is positive-negative-positive triode, the emitter that the input end of the 4th switching tube Q3 is triode, the collector that the output terminal of the 4th switching tube Q3 is triode, the base stage that the control end of the 4th switching tube Q3 is triode.In other embodiments, the 4th switching tube Q3 also can adopt other suitable switching device of response time, for example P channel mosfet.
Refer to Fig. 4, independent current source modular converter 30 comprises the 3rd divider resistance R17, stabilivolt D1 and second switch pipe Q4.Second switch pipe Q4 comprises input end, output terminal and control end, and the input end of second switch pipe Q4 is used for connecting externally fed power supply DC_IN, is connected to the 3rd divider resistance R17 between the input end of second switch pipe Q4 and control end; The output terminal of independent current source modular converter 30 (output 3.3V direct current) is the output terminal of second switch pipe Q4, the 3rd divider resistance R17 connects one end of the control end of second switch pipe Q4 and passes through stabilivolt D1 ground connection, and one end of stabilivolt D1 ground connection is the anode of stabilivolt D1.
In the embodiment shown in fig. 4, second switch pipe Q4 is NPN type triode, the collector that the input end of second switch pipe Q4 is triode, the emitter that the output terminal of second switch pipe Q4 is triode, the base stage that the control end of second switch pipe Q4 is triode.
According to the resistance of the specification of external power adapter (having determined the rated voltage of externally fed power supply) choose reasonable the 4th divider resistance R1 and the 5th divider resistance R2, just can set power down threshold value, make the accurate onset of Power Monitoring Unit 10.The first delay capacitor C1 is used for finely tuning sequential, and the first time delay resistance R5 and the second delay capacitor C2 are for regulating the time delay of write-protect module 20, and the second time delay resistance R10 and the 3rd delay capacitor C4 are for regulating the time delay of reseting module 40.Power supply supervisory circuit 10 sends after 3 ~ 5 milliseconds of alarm signals, and write-protect module 20 output low levels are to the write-protect pin of flash memory; Send after 8 ~ 10 milliseconds of alarm signals reseting module 40 output reset signals.Because reseting module 40 need to just onset after write-protect module 20 action, so the capacitance of the 3rd delay capacitor C4 should be larger than the capacitance of the second delay capacitor C2.
In an embodiment, the model of reset chip U1 is AIC809N therein, and the model of triode Q1 is 2N3904, the model of triode Q2 is 2N3906, the model of triode Q3 is 2N3906, and the model of triode Q4 is S8050, and stabilivolt D1 adopts the stabilivolt that burning voltage is 3.9V.Also can select as required according to actual conditions the components and parts of other model in other embodiments.
The above-mentioned power down protection sequential circuit for flash memory; when externally fed power supply drops to power down threshold value when following (now the required Ge of central processing unit road supply voltage is also within rated range); first Power Monitoring Unit 10 moves; produce low level alarm signal; this system of notice central processing unit is about to power down, to allow central processing unit carry out corresponding backup and protection action.After 3-5 millisecond, write-protect module 20 comes into force, and forbids that central processing unit carries out any write operation to flash memory; After alarm signal produces 8 ~ 10 milliseconds, reseting module 40 starts, and central processing unit, NOR FLASH and all peripheral hardwares with reset function all enter reset mode, until power down finishes.Thereby guaranteed in whole power down process, whole system, can something unexpected happened in a kind of definite state.Independent current source modular converter 30 can guarantee internal power supply (above-mentioned 3.3V direct current) last power-off in system, guarantees that this is for the power down protection sequential circuit reliably working of flash memory.
The above embodiment has only expressed several embodiment of the present invention, and it describes comparatively concrete and detailed, but can not therefore be interpreted as the restriction to the scope of the claims of the present invention.It should be pointed out that for the person of ordinary skill of the art, without departing from the inventive concept of the premise, can also make some distortion and improvement, these all belong to protection scope of the present invention.Therefore, the protection domain of patent of the present invention should be as the criterion with claims.
Claims (10)
1. for a power-down protection circuit for flash memory, it is characterized in that, comprise Power Monitoring Unit and electronic switch unit, described Power Monitoring Unit connecting electronic switch element, described electronic switch unit is for connecting the write-protect pin of flash memory; Described Power Monitoring Unit is used for obtaining externally fed power supply, and when the voltage of described externally fed power supply is less than power down threshold value, controls described electronic switch unit output low level to described write-protect pin;
Described electronic switch unit comprises the first divider resistance, the second divider resistance, pull down resistor and the first switching tube, described the first switching tube comprises input end, output terminal and control end, the output terminal of described the first switching tube is used for connecting described write-protect pin, and the output terminal of described the first switching tube is by described pull down resistor ground connection; The input end of described the first switching tube is for connecting the power supply of described flash memory, and the input end of described the first switching tube connects the control end of described the first switching tube by described the second divider resistance; The control end of described the first switching tube connects described Power Monitoring Unit by described the first divider resistance.
2. the power-down protection circuit for flash memory according to claim 1; it is characterized in that; described the first switching tube is positive-negative-positive triode; the input end of described the first switching tube is the emitter of described triode; the output terminal of described the first switching tube is the collector of described triode, the base stage that the control end of described the first switching tube is described triode.
3. the power-down protection circuit for flash memory according to claim 1, it is characterized in that, described Power Monitoring Unit comprises second switch pipe, the 3rd divider resistance, the 4th divider resistance and the 5th divider resistance, described second switch pipe comprises input end, output terminal and control end, and the input end of described second switch pipe connects described externally fed power supply by described the 3rd divider resistance; The output head grounding of described second switch pipe; The control end of described second switch pipe connects described externally fed power supply by described the 4th divider resistance, and the control end of described second switch pipe is by described the 5th divider resistance ground connection.
4. the power-down protection circuit for flash memory according to claim 3, it is characterized in that, described second switch pipe is NPN type triode, the input end of described second switch pipe is the collector of described NPN type triode, the output terminal of described second switch pipe is the emitter of described NPN type triode, and the control end of described second switch pipe is the base stage of described NPN type triode; Described Power Monitoring Unit also comprises in parallel for adjusting the electric capacity of sequential with described the 5th divider resistance.
5. for a power down protection sequential circuit for flash memory, it is characterized in that, comprise independent current source modular converter, Power Monitoring Unit, write-protect module and reseting module; Described independent current source modular converter is used for externally fed power supply being converted to internal power supply and exporting by the output terminal of independent current source modular converter, thereby realizes the last power down of internal power supply in described externally fed power supply power-fail process; Described Power Monitoring Unit is used for obtaining externally fed power supply, and when the voltage of described externally fed power supply is less than power down threshold value outputting alarm signal;
Described write-protect module comprises trigger element and electronic switch unit; Described trigger element is connected with output terminal, Power Monitoring Unit and the electronic switch unit of described independent current source modular converter, described electronic switch unit is for connecting the write-protect pin of flash memory, and described trigger element triggers described electronic switch unit output low level to described write-protect pin under the alarm signal of described Power Monitoring Unit is controlled;
Described reseting module is connected with Power Monitoring Unit with the output terminal of described independent current source modular converter, for export reset signal when receiving described alarm signal;
Described electronic switch unit comprises the first divider resistance, the second divider resistance, pull down resistor and the first switching tube, described the first switching tube comprises input end, output terminal and control end, the output terminal of described the first switching tube is used for connecting described write-protect pin, and the output terminal of described the first switching tube is by described pull down resistor ground connection; The input end of described the first switching tube is for connecting the output terminal of described independent current source modular converter, and the input end of described the first switching tube connects the control end of described the first switching tube by described the second divider resistance, the control end of described the first switching tube connects trigger element by described the first divider resistance.
6. the power down protection sequential circuit for flash memory according to claim 5, it is characterized in that, described independent current source modular converter comprises the 3rd divider resistance, stabilivolt and second switch pipe, described second switch pipe comprises input end, output terminal and control end, the input end of described second switch pipe is used for connecting described externally fed power supply, between the input end of described second switch pipe and control end, be connected to described the 3rd divider resistance, the output terminal of described independent current source modular converter is the output terminal of described second switch pipe, described the 3rd divider resistance connects one end of the control end of described second switch pipe and passes through described stabilivolt ground connection, one end of described stabilivolt ground connection is the anode of stabilivolt.
7. the power down protection sequential circuit for flash memory according to claim 5, it is characterized in that, described Power Monitoring Unit comprises microprocessor reset chip, the 4th divider resistance, the 5th divider resistance, the first pull-up resistor, the first current-limiting resistance and the first delay capacitor;
The power supply input pin of described microprocessor reset chip connects described externally fed power supply by described the 4th divider resistance, and described power supply input pin is by described the 5th divider resistance ground connection, and described the first delay capacitor is in parallel with described the 5th divider resistance; The lower margin ground connection of described microprocessor reset chip; The reset pin of described microprocessor reset chip is used for exporting described alarm signal; Described reset pin connects the output terminal of described independent current source modular converter by described pull-up resistor, described reset pin connects the interrupt pin of central processing unit by described the first current-limiting resistance.
8. the power down protection sequential circuit for flash memory according to claim 5, it is characterized in that, described trigger element comprises the first time delay resistance, the second pull-up resistor, the second delay capacitor and the 3rd switching tube, and described the 3rd switching tube comprises input end, output terminal and control end;
The input end of described the 3rd switching tube connects the output terminal of described independent current source modular converter by described the second pull-up resistor, the input end of described the 3rd switching tube also connects described electronic switch unit by described the first divider resistance; The output head grounding of described the 3rd switching tube; The control end of described the 3rd switching tube passes through described the second delay capacitor ground connection, and connects described Power Monitoring Unit to obtain described alarm signal by described the first time delay resistance.
9. the power down protection sequential circuit for flash memory according to claim 5, is characterized in that, described electronic switch unit also comprises the second current-limiting resistance of being located between the output terminal of described the first switching tube and the write-protect pin of described flash memory.
10. the power down protection sequential circuit for flash memory according to claim 5, is characterized in that, described reseting module comprises the second time delay resistance, the 3rd pull-up resistor, the 3rd delay capacitor, filter capacitor and the 4th switching tube; Described the 4th switching tube comprises input end, output terminal and control end;
The input end of described the 4th switching tube connects the output terminal of described independent current source modular converter by described the 3rd pull-up resistor; The output head grounding of described the 4th switching tube, the control end of described the 4th switching tube passes through described the 3rd delay capacitor ground connection, and connects described Power Monitoring Unit to obtain described alarm signal by described the second time delay resistance; Described the 3rd pull-up resistor connects one end of described filter capacitor for exporting described reset signal.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201210226126.1A CN103531233B (en) | 2012-07-03 | 2012-07-03 | For the power-down protection circuit of flash memory and power down protection sequence circuit |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201210226126.1A CN103531233B (en) | 2012-07-03 | 2012-07-03 | For the power-down protection circuit of flash memory and power down protection sequence circuit |
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| CN103531233A true CN103531233A (en) | 2014-01-22 |
| CN103531233B CN103531233B (en) | 2018-05-22 |
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| CN201210226126.1A Active CN103531233B (en) | 2012-07-03 | 2012-07-03 | For the power-down protection circuit of flash memory and power down protection sequence circuit |
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Cited By (14)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104332174A (en) * | 2014-11-27 | 2015-02-04 | 天津天地伟业数码科技有限公司 | Memory chip writing protective circuit and memory chip writing protective method applied to security product |
| CN104731723A (en) * | 2015-03-19 | 2015-06-24 | 青岛海信电器股份有限公司 | Power-off protection method and device for storage device |
| CN105511978A (en) * | 2015-12-05 | 2016-04-20 | 中国航空工业集团公司洛阳电光设备研究所 | Power-down protection method and system for file system in recording equipment |
| CN107563229A (en) * | 2017-09-14 | 2018-01-09 | 苏州恒成芯兴电子技术有限公司 | A kind of power down protection module suitable for solid state hard disc |
| WO2018040969A1 (en) * | 2016-08-31 | 2018-03-08 | 福建联迪商用设备有限公司 | Method and device for improving reliability of nand flash memory |
| CN109188242A (en) * | 2018-08-29 | 2019-01-11 | 郑州云海信息技术有限公司 | A kind of time sequence test method, device and VR chip |
| CN109192234A (en) * | 2018-07-13 | 2019-01-11 | 上海移远通信技术股份有限公司 | A kind of protection circuit and communication module |
| CN109407592A (en) * | 2018-12-18 | 2019-03-01 | 安徽庆宇光电科技有限公司 | A kind of remote sensing monitoring control circuit |
| CN109410868A (en) * | 2018-12-06 | 2019-03-01 | 深圳市华星光电半导体显示技术有限公司 | Display panel drive device |
| CN110265078A (en) * | 2019-06-24 | 2019-09-20 | 长江存储科技有限责任公司 | A kind of power-down protection circuit |
| CN112948183A (en) * | 2021-03-30 | 2021-06-11 | 西安微电子技术研究所 | Software and hardware combined embedded device and method |
| CN113138938A (en) * | 2020-01-19 | 2021-07-20 | 深圳信可通讯技术有限公司 | Memory protection device and method and electronic equipment |
| CN113218042A (en) * | 2021-04-29 | 2021-08-06 | Tcl空调器(中山)有限公司 | Air conditioner outdoor unit parameter modification method and device, storage medium and air conditioning system |
| CN116911348A (en) * | 2023-09-07 | 2023-10-20 | 四川荣川通用航空有限责任公司 | SD card data transmission system based on Beidou short message |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4422163A (en) * | 1981-09-03 | 1983-12-20 | Vend-A-Copy, Inc. | Power down circuit for data protection in a microprocessor-based system |
| CN1797886A (en) * | 2004-12-23 | 2006-07-05 | 鸿富锦精密工业（深圳）有限公司 | Circuit for preventing chip from misoperation |
| CN102023938A (en) * | 2009-09-18 | 2011-04-20 | 鸿富锦精密工业（深圳）有限公司 | Electronic device and power off protection method |
-
2012
- 2012-07-03 CN CN201210226126.1A patent/CN103531233B/en active Active
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4422163A (en) * | 1981-09-03 | 1983-12-20 | Vend-A-Copy, Inc. | Power down circuit for data protection in a microprocessor-based system |
| CN1797886A (en) * | 2004-12-23 | 2006-07-05 | 鸿富锦精密工业（深圳）有限公司 | Circuit for preventing chip from misoperation |
| CN102023938A (en) * | 2009-09-18 | 2011-04-20 | 鸿富锦精密工业（深圳）有限公司 | Electronic device and power off protection method |
Cited By (19)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104332174A (en) * | 2014-11-27 | 2015-02-04 | 天津天地伟业数码科技有限公司 | Memory chip writing protective circuit and memory chip writing protective method applied to security product |
| CN104731723A (en) * | 2015-03-19 | 2015-06-24 | 青岛海信电器股份有限公司 | Power-off protection method and device for storage device |
| CN105511978A (en) * | 2015-12-05 | 2016-04-20 | 中国航空工业集团公司洛阳电光设备研究所 | Power-down protection method and system for file system in recording equipment |
| CN105511978B (en) * | 2015-12-05 | 2019-01-29 | 中国航空工业集团公司洛阳电光设备研究所 | A kind of recording equipment file system power-off protection method and system |
| WO2018040969A1 (en) * | 2016-08-31 | 2018-03-08 | 福建联迪商用设备有限公司 | Method and device for improving reliability of nand flash memory |
| CN107563229A (en) * | 2017-09-14 | 2018-01-09 | 苏州恒成芯兴电子技术有限公司 | A kind of power down protection module suitable for solid state hard disc |
| CN109192234A (en) * | 2018-07-13 | 2019-01-11 | 上海移远通信技术股份有限公司 | A kind of protection circuit and communication module |
| CN109188242B (en) * | 2018-08-29 | 2021-08-31 | 郑州云海信息技术有限公司 | Time sequence testing method and device and VR chip |
| CN109188242A (en) * | 2018-08-29 | 2019-01-11 | 郑州云海信息技术有限公司 | A kind of time sequence test method, device and VR chip |
| CN109410868A (en) * | 2018-12-06 | 2019-03-01 | 深圳市华星光电半导体显示技术有限公司 | Display panel drive device |
| CN109407592A (en) * | 2018-12-18 | 2019-03-01 | 安徽庆宇光电科技有限公司 | A kind of remote sensing monitoring control circuit |
| CN109407592B (en) * | 2018-12-18 | 2024-01-19 | 安徽庆宇光电科技有限公司 | Remote sensing monitoring control circuit |
| CN110265078A (en) * | 2019-06-24 | 2019-09-20 | 长江存储科技有限责任公司 | A kind of power-down protection circuit |
| CN113138938A (en) * | 2020-01-19 | 2021-07-20 | 深圳信可通讯技术有限公司 | Memory protection device and method and electronic equipment |
| CN112948183A (en) * | 2021-03-30 | 2021-06-11 | 西安微电子技术研究所 | Software and hardware combined embedded device and method |
| CN112948183B (en) * | 2021-03-30 | 2023-05-12 | 西安微电子技术研究所 | Software and hardware combined embedded device and method |
| CN113218042A (en) * | 2021-04-29 | 2021-08-06 | Tcl空调器(中山)有限公司 | Air conditioner outdoor unit parameter modification method and device, storage medium and air conditioning system |
| CN116911348A (en) * | 2023-09-07 | 2023-10-20 | 四川荣川通用航空有限责任公司 | SD card data transmission system based on Beidou short message |
| CN116911348B (en) * | 2023-09-07 | 2023-12-01 | 四川荣川通用航空有限责任公司 | SD card data transmission system based on Beidou short message |
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