File Name: difference between eprom and eeprom .zip
EEPROM electrically erasable programmable read-only memory is user-modifiable read-only memory that can be erased and reprogrammed written to repeatedly through the application of higher than normal electrical voltage. If you have a toddler who is learning how to write, this is also an ideal tool for them.
A kind of performance of testing integrated circuits and the method for fault thereof are especially tested the performance of electric erasable electrically-programmable memory and the method for fault thereof. Storer is the main memory unit of various robot calculator, and is widely used in other electronic equipment.
Basic demand to semiconductor memory is a high precision, high capacity, low-power consumption. PROM user can finish programing work promptly information being written in the storer to useless fuse opening as required, in case programming finishes, just can't change, so the user is only once able to programme again. The pipe of canned data adopts floating gate structure in this type of ROM storage unit of EPROM, utilize and have or not electric charge to come canned data on the floating boom, when the needs reprogramming, can once all wipe former information of depositing with ultraviolet ray earlier, enroll new content more as required, can programme repeatedly, EPROM can not word for word wipe the content of depositing, wiping needs ultraviolet light, and the erasing time is long, uses inconvenience.
In these 3 types, EEPROM has adopted floating boom tunnel oxide structure, and it utilizes tunnel effect to realize the storage of information and wipes. It can be realized wiping word for word under need not the condition of auxiliary voltage and write.
Have erasable convenience, characteristics rapidly, therefore obtained using widely. Realize that the erasable used time far surpasses to patrol seizes the used time of electric circuit inspection because EEPROM storage unit erasable is the tunnel effect by super thin oxide layer, cause the unusual time-consuming of the test of EEPROM.
In actual design, production and test process, EEPROM failure reasons more complicated might be the error in the design, also might technologic deviation cause. Common problem has erasable high pressure VPP not enough in the design, sensitive sense amplifier circuit time-delay is excessive etc.
The invention provides a kind of performance of electric erasable electrically-programmable memory and method of fault thereof of testing, it is consuming time long to be intended to solve test electric erasable electrically-programmable memory, and the technical matters of finding out its fault.
For realizing that the technical program may further comprise the steps: under voltage conditions, 1 is adopted full wiping to write the FF00 pattern entirely and read then to the invention of the method for a kind of performance of testing the electric erasable electrically-programmable memory and fault thereof; 2 writing the 55AA pattern entirely with full wiping reads then; 3 wiping the page or leaf WriteMode with page or leaf reads then; 4 wiping the byte WriteMode with byte reads then;.
Described voltage can be low pressure, and numerical range is 2. If its performance has problem, and is further comprising the steps of: by internal element and current testing circuit to the electric erasable electrically-programmable memory, the size of current of 5 test inside unit; 6 add to the electric erasable electrically-programmable memory needed high pressure when erasable, the size of current of test inside unit. As shown in Figure 1: whole process is done the test of same steps as respectively to EEPROM under 3 voltages, at first detects full wiping and write entirely under low-voltage 2.
By low-voltage 2. If test can't pass, by internal element and current testing circuit to the electric erasable electrically-programmable memory, the size of current of 1 test inside unit; 2 add to the electric erasable electrically-programmable memory needed high pressure when erasable, the size of current of test inside unit.
As shown in Figure 2: this is the module map of an EEPROM, and input signal mainly contains sheet choosing CE , read signal OE , write signal WE , address signal and input data signal, also has signal, the outputting data signals of some test usefulness in addition.
The wiping of EEPROM and the process of writing are carried out continuously, earlier the data in the address that EEPROM is chosen wipe " 1 " entirely, according to the numerical value on the data line several bits for " 0 " are write as " 0 " again for " 0 ", all need the support of high pressure in the process of wiping and writing, this high pressure is generally realized by the voltage hoisting module in the sheet.
In addition, can move in certain sequence, need sequential control circuit various piece to be carried out the read-write steering logic unit 14 of beat control in order to make the storer each several part.
The number of words of N representative storage, M represents the figure place of each word. For can be correct write or the sensing element array in the information of a certain unit, must compile storage unit and go up number promptly giving unique address of each storage unit , seek storage unit by the address, the circuit that can realize address selection is in code translator.
The storer that the n address input end is arranged, its storage unit that can be addressed is 2 N Individual. Because the circuit structure of each storage unit is the same, in order to save chip area, they always line up matrix form in integrated circuit, at this moment, in order to select a certain storage unit, need row address and column address decoder.
In addition, 0 of storage unit or 1 can not directly read when reading EEPROM, must therefore, the support of sensing circuit must be arranged also when read operation through the amplification of sensor amplifier.
The data latches 15 of wanting handlebar operation address and data latching to live in erasable process to guarantee the stable of in erasable process data, produces the circuit for producing high voltage 16 of erasable high pressure in addition, produces the high pressure of revising EEPROM data institute palpus.
For the function that can realize that EEPROM is all, also need the sequential that control circuit control EEPROM class of operation and control signal take place, this part circuit mainly is made up of counter and command generator, each instructs counter controls the effective time, and erasable process can be carried out as requested. Command generator combines with counter, according to the requirement of external signal, produces corresponding instruction, makes the various piece energy operate as normal of EEPROM.
As shown in Figure 3: the storage tube of EEPROM comprises the polysilicon gate of two superimposed, below one deck be floating boom 21, be stored pipe gate oxide 24 on every side and surround, be hedged off from the outer world, leakage current is very little under the general read states, is convenient to preserve electric charge. Top one deck polysilicon is a control gate 22, and floating gate polysilicon covers the place simultaneously, and at the extension and drain region 25 crossovers of diffusion region, in this zone, has the super thin oxide layer about a 10nm between floating boom and drain region, is called tunnel oxidation layer This tunnel effect is reversible, if control gate 22 ground connection, leaks level and adds 16V voltage, and then electronics is gone to drain electrode from floating boom 21 oxide layer 23 of passing through tunnel, and makes floating gate discharging.
Storage tube is placed on drain region 23 to tunnel oxidation layer 23, and the byte erase feature can be provided, and this just requires the super thin oxide layer of growing high-quality on heavily doped drain region Because tunnel current has very strong dependence to the voltage at oxide two ends, the every increase of impressed voltage 0.
So just require during erasable, to make the voltage difference at tunnel oxide 23 two ends must surpass 14V.
To guarantee the operating characteristic and the long-term reliability of storage tube in addition, prevent that tunnel oxidation layer 23 is breakdown, require the peak value electric field on the restriction tunnel oxidation layer Require voltage to have the gradual rising edge of us for this reason.
As shown in Figure 4: because the deposit data of EEPROM in the floating boom that an oxidized silicon surrounds, as long as control gate or drain electrode have a high voltage differential to floating boom, will produce tunnel effect, floating boom is discharged and recharged, change the data in the EEPROM. When read operation, the EEPROM internal data reduces to read time-delay by sensitive sense amplifier circuit output data.
When sensitive sense amplifier circuit was worked, " reading 31 " put height, and by making internal element 33 conductings after the reverser 32, its input end provides a direct current biasing to the storage tube of storage data. If the data of selected storage tube internal memory are " 1 ", then this storage tube ends, and the input end electric current of sensitive sense amplifier circuit 34 is 0, and the open-circuit voltage of sensitive sense amplifier circuit 34 is about 1.
The data of selected storage tube internal memory are " 0 ", then this storage tube conducting, and the input end of sensitive sense amplifier circuit has a certain amount of input current, and the voltage of sensitive sense amplifier circuit 34 input ends can descend. This small variation has finally formed the difference of high-low level through the amplification of sensitive sense amplifier circuit. Therefore, the difference between current under the storage tube conducting cut-off state is an important step that influences EEPROM, and its performance is subjected to the influence of technology very big.
In process of production, the technological requirement of EEPROM storage unit is higher, and abnormal conditions such as storage unit electric leakage take place in regular meeting, as long as this just can judge by the electric current of surveying sensitive sense amplifier circuit.
In general, sensitive sense amplifier circuit input current is 0uA when data in the unit are " 1 ", sensitive sense amplifier circuit input current should be greater than 20uA when data in the unit are " 0 ", if the super thin oxide layer thickness low LCL can make the electronics on the floating boom slowly run away, the situation that sensitive sense amplifier circuit input current rises gradually in the time of then can occurring data for " 1 " under surveying current-mode, if the blocked up meeting of super thin oxide layer makes the electronics of control gate or drain terminal can't arrive the situation of floating boom smoothly, the situation that sensitive sense amplifier circuit input current rises gradually less than 20uA or electric current in the time of then can occurring data for " 0 " under surveying current-mode.
Our ad hoc measuring unit current paths in EEPROM now, if survey the electric current of certain unit, in this element, write earlier predetermined data, read this unit again, last " electric current selects 35 " of beating high each bit successively, make bias current deliver to the outside, link on the galvanometer, so just can detect the current conditions of each unit by special-purpose resolver through " electric current pin 36 ".
When testing, can only test the electric current of a unit at every turn, can not make two " electric current selections " for high simultaneously. The invention is a method to test EEPROM performance and failure, including the steps on voltage condition: 1 adopting full-erase full-write mode FF00 to read; 2 using full-erase full-write mode 55AA to read again and again; 3 using page-erase page-write mode to read; 4 using byte-erase byte-write mode to read; if something is wrong with its performance, it also includes the steps: by the inner unit and current testing circuit of EEPROM, 5 testing the current magnitude of the inner unit; 6 applying the needed voltage of erasing and writing EEPROM, to measure the current magnitude of the inner unit.
A kind of performance of electric erasable electrically-programmable memory and method of fault thereof of testing Technical field A kind of performance of testing integrated circuits and the method for fault thereof are especially tested the performance of electric erasable electrically-programmable memory and the method for fault thereof.
Background technology Storer is the main memory unit of various robot calculator, and is widely used in other electronic equipment. Summary of the invention The invention provides a kind of performance of electric erasable electrically-programmable memory and method of fault thereof of testing, it is consuming time long to be intended to solve test electric erasable electrically-programmable memory, and the technical matters of finding out its fault.
For realizing that the technical program may further comprise the steps: under voltage conditions, 1 is adopted full wiping to write the FF00 pattern entirely and read then to the invention of the method for a kind of performance of testing the electric erasable electrically-programmable memory and fault thereof; 2 writing the 55AA pattern entirely with full wiping reads then; 3 wiping the page or leaf WriteMode with page or leaf reads then; 4 wiping the byte WriteMode with byte reads then; Described voltage can be low pressure, and numerical range is 2.
Description of drawings Fig. CNA en. USB2 en. USB1 en. USA en. Programmable read only memory integrated circuit with bit-check and deprogramming modes and methods for programming and testing said circuit.
CNB en. Method of reading NAND memory to compensate for coupling between storage elements. CNC en. Method and circuit for reading fuse cells in a nonvolatile memory during power-up.
DET2 en. Cross point variable resistance nonvolatile memory device and method of writing thereby. JPB2 en. Nonvolatile semiconductor memory device having a status register and test method for the same. KRB1 en. Memory system, method for reading data stored in the memory system and method for executed by the memory system. Buffer circuit used in a semiconductor device operating by different supply potentials and method of operating the same. One-time programable memory with additional programming time to ensure hard breakdown of the gate insulating film.
What's the difference between Scripting and Programming Languages? This is a type of PROM that can be completely removed or erased if it would be exposed to ultraviolet rays. Once the data has been erased, it can be reprogrammed so that new data can be stored. EEPROM is a user-modifiable memory that can be constantly erased and re-programmed by users through applying higher than normal electrical voltage generated externally or internally. Menghapus membutuhkan peralatan khusus dan dapat dilakukan dalam jumlah terbatas. Please use ide.
Before writing, the contents inside must be irradiated with ultraviolet rays on the transparent window on its IC card to clear it. It is a type of memory which can only be modified once not again and again. The data can be erased and reprogrammed by using ultraviolet UV light. Dov Frohman. These don't have a "window".
EPROM and EEPROM both are erasable and can be reprogrammed, but the basic difference between them is that EPROM is erased using Ultra violet rays whereas, EEPROM can be erased using electric signals.
We all are aware of ROM i.
Computer memory that can retrieve stored data after a power supply has been turned off and back on is called non-volatile. It is an array of floating-gate transistors individually programmed by an electronic device that supplies higher voltages than those normally used in digital circuits. Once programmed, an EPROM can be erased by exposing it to strong ultraviolet light source such as from a mercury-vapor lamp. EPROMs are easily recognizable by the transparent fused quartz window on the top of the package, through which the silicon chip is visible, and which permits exposure to ultraviolet light during erasing. Development of the EPROM memory cell started with investigation of faulty integrated circuits where the gate connections of transistors had broken.
A kind of performance of testing integrated circuits and the method for fault thereof are especially tested the performance of electric erasable electrically-programmable memory and the method for fault thereof. Storer is the main memory unit of various robot calculator, and is widely used in other electronic equipment. Basic demand to semiconductor memory is a high precision, high capacity, low-power consumption. PROM user can finish programing work promptly information being written in the storer to useless fuse opening as required, in case programming finishes, just can't change, so the user is only once able to programme again.
EEPROM also E 2 PROM stands for electrically erasable programmable read-only memory and is a type of non-volatile memory used in computers, integrated in microcontrollers for smart cards and remote keyless systems , and other electronic devices to store relatively small amounts of data by allowing individual bytes to be erased and reprogrammed. There is no clear boundary dividing the two, but the term "EEPROM" is generally used to describe non-volatile memory with small erase blocks as small as one byte and a long lifetime typically 1,, cycles. As of , flash memory costs much less than byte-programmable EEPROM and is the dominant memory type wherever a system requires a significant amount of non-volatile solid-state storage. EEPROMs, however, are still used on applications that only require small amounts of storage, like in serial presence detect.
It is a nonvolatile memory.
ОНА ОТБРОСИТ АНБ НАЗАД НА ДЕСЯТИЛЕТИЯ. Сьюзан как во сне читала и перечитывала эти строки. Затем дрожащими руками открыла следующее сообщение. ТО: NDAKOTAARA. ANON.
Сьюзан не могла не поразить идея глобального прорыва в области разведки, который нельзя было себе даже представить. И он попытался сделать это в одиночку. Похоже, он и на сей раз добьется своей цели. Ключ совсем. Танкадо мертв.
Последний месяц был для Лиланда Фонтейна временем больших ожиданий: в агентстве происходило нечто такое, что могло изменить ход истории, и, как это ни странно директор Фонтейн узнал об этом лишь случайно. Три месяца назад до Фонтейна дошли слухи о том, что от Стратмора уходит жена. Он узнал также и о том, что его заместитель просиживает на службе до глубокой ночи и может не выдержать такого напряжения. Несмотря на разногласия со Стратмором по многим вопросам, Фонтейн всегда очень высоко его ценил. Стратмор был блестящим специалистом, возможно, лучшим в агентстве.
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