In view of the fact that the environment question receives people’s widespread attention more and more, the global electron profession started to devote in promotes the low energy consumption in the market the product. The white electrical appliances’ energy consumption rank is the sales data which the people pay attention, the reference energy consumption height is helpful to the control electrical bill; Now, not only we realize the energy consumption to be low may reduce the electrical bill, moreover is also helpful to the environmental protection.
Project engineers diligently are reducing the product the power loss, hoped that lets the product (for example 25 years) only need a battery in the entire life cycle then. But the present trend of development is: The ultra low power loss to not be needing battery’s new product type opening nearly, and by “energy crop” the concept (i.e. obtains energy for the foundation from environment to come for product power supply).
These product’s key is can enter the dormant state by the extremely low power loss, its power loss accepts a lower status the equipment basically to close down likely, even if because the dormant state also consumed power. Moreover so long as product in restarting time can remember its condition, the close-down is not a problem. Therefore, has the low operating current and reads in the durable nonvolatile storage to arise at the historic moment high. Has these characteristic memory, may produce does not need to insert the electricity and to replace the new battery’s equipment.
In view of these requests, we have a look at the non-volatility serial storage technology, namely uses in the memory layout data the general memory structure power loss. Here has compared F-RAM (poss ferroelectric random access memory), EEPROM and dodges saves three kind of technologies. Because dodges saves can only use the serial peripheral device connection (SPI), we carry on it with SPI edition EEPROM and F-RAM the comparison.
For this research, we calculated and compare each kind of memory technology execution to read in the energy which consumed with the cleaning. The energy is one very good comparison method, because it had considered the duty duration and carries out the electrical energy which the duty needs.
Energy = power * time. The use formula “a power = volt * ampere” replaces the power, may obtain “an energy = volt * ampere * time”.
We choose to read in carry on the comparison with the cleaning, the difference is biggest because of these three kind of memory technology in these duties, but reads in the process, even if when the working speed, the voltage and the current consumption are different, to each kind of technology also approximately same. Some people possibly believed that serial interface’s speed plays the vital role in here, however, when carries on the double counting by the different SPI main line speed to the same part, consumes the total energy maintains approximately invariable (I believed that Einstein’s law of conservation of energy is suitable in here).
In order to eliminate any with calculates the SPI main line expenses related question (for instance issue orders and establishes address) the influence, we have used the considerable data quantity, said is 64Kb accurately, carries on the comparison.
In addition, EEPROM with dodges saves the technology to use the page buffer, lets a greater quantity the data be possible also to read, thus speeds up reads in the process. When the data quantity is the page integer, these page’s efficiency is highest. F-RAM does not have the page buffer, because it can by transport the data similarly quick speed write data with the SPI main line.
F-RAM and the EEPROM erasing time, has not dodged saves, then requires the quite long time to clean the sector. Therefore, we will compare it to require the long time to clean the 64Kb data and to read in the recent data.
Finally, must know that the manufacturer mentioned when power loss is not the use consistent standard. Certain equipment possibly assign under Vcc=1.8V to work, but its material table provides is actually Vcc=2.5V. Here uses the value is the worst situation value which in the material table stipulated.
The serial data dodges when saves the cleaning page/sector, needs to consume the massive energies, because these operations time-consuming are long. EEPROM with dodges saves the use polling (polling) technology, but is not waited for section of worst situations need the time completes the operation, thus reduced both’s energy request. The material table does not have the clear demonstration, when reads in/the cleaning completes, reads in electric current which/in the cleaning cycle consumes whether automatic gradually to reduce or whether to continue.
The above result indicated that the F-RAM technology compares with other nonvolatile storage technology has the obvious superiority. Its energy consumption is only is situated the second best alternative scheme 1/60, is only the operation best serial data dodges saves approximately 1/400.
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