The non-volatile memory as a smart card storage unit mainly includes an electrically rewritable programmable read only memory EEPROM, a flash memory, a flash memory, and a ferroelectric memory FRAM.
EEPROM is the most typical electrically rewritable non-volatile memory. It is a non-volatile semiconductor memory developed since the 1980s. It is electrically programmable, erasable/writable, and flexible. The process basis of EEPROM is CMOS technology. As CMOS technology develops to sub-micron, the integration of EEPROM is constantly improving.
Both Flash Memory and FRAM are a new generation of non-volatile memory. Flash Memory was introduced in 1987. It is the product of mature EEPROM and the development of semiconductor technology to sub-micron technology and large-capacity rewritable memory, while FRAM It was in the 1970s that there was a breakthrough in key technologies that did not enter the industrialization stage until the 1990s. It is a capacitor memory that uses ferroelectric thin films for memory data. Due to the use of ferroelectric thin films on memory cells, FRAM has the advantages of high speed, high frequency rewriting, low power consumption and non-volatile. In addition, FRAM can perform read/write operations under low voltage conditions, especially for smart cards and portable devices that require low power consumption.
One. Performance comparison between Flash Memory and EEPROM:
Both Flash memory and EEPROM are electrically erasable and programmable memories. Their principle is to store data in the form of charge on the floating gate electrode. Compared with EEPROM, Flash has unparalleled advantages in terms of integration. Because Flash Memory uses a single-tube unit, it can achieve high integration, and its cell area is only 1/4 of that of conventional EEPROM.
There are two main programming methods for Flash Memory cells: channel hot electron injection (CHE) and tunneling (Fowler-Nordheim). Channel hot electron injection (CHE) is currently the most widely used programming method for Flash Memory. The programming time for channel hot electron injection CHE is on the order of microseconds, while the tunneling (Fowler-Nordheim) programming time is typically on the order of milliseconds. The way EEPROM is programmed is tunneling. Therefore, Flash memory programming time is faster than EEPROM.
The following table shows the performance comparison of Flash Memory and EEPROM:
Durability
density
In the unit
Number of transistors
Charging
mechanism
Discharge
mechanism
program
the complexity
erase
EEPROM
it is good
in
double
tunnel
effect
tunnel
effect
simple
When writing
Automatic erasure
Flash
good
high
single
electronic
effect
tunnel
effect
complex
Word group
Erase
two. Performance comparison between FRAM and EEPROM and Flash memory:
The basic principle of the FRAM memory cell is the ferroelectric effect, which is a ferroelectric memory device that is stored in a spontaneously polarized form of a ferroelectric thin film. Since the FRAM controls the spontaneous polarization of the ferroelectric capacitor through an external electric field, and through hot electron injection or Compared with Flash memory, which has a tunneling effect and a write operation, FRAM has a fast write speed (more than 1000 times that of EEPROM and Flash) because it does not require high voltage during erasing, so the power consumption during writing is large. To reduce (1/1000-1/100000 for EEPROM and Flash), it is especially suitable for low power applications such as contactless cards or dual interface cards. In addition, since the tunnel oxide film is not required, the number of times of data rewriting is greatly improved compared with flash memory and EEPROM (10 5 - 10 6 for EEPROM or flash, and 10 12 or more for FRAM).
The following table shows the performance comparison between FRAM and Flash Memory and EEPROM:
Technology type
FRAM
EEPROM
Flash memory
Data storage
10 years
10 years
10 years
Unit structure
2T/2C, 1T/1C
2T
1T
Unit size
medium
medium
small
Write voltage
2 — 5V
12--18V
10--12V
Number of rewrites
10 10 --10 12
10 5 — 10 6
10 5 — 10 6
Average power consumption
low
medium
medium
This classify is set for manual Breast Pump.To some degree,a suitable breast pump is essential for breastfeeding mons.Some mothers will choose a manual one,because it is light and portable.Besides,it is cheaper than an electric one.The manual one is made of PP and silicone material,BPA free,food grade.
Manual Breast Pump,Breast Milk Pump,Milk Extractor,Hand Breast Pump
Jiangsu Xinbei Electrical Appliances Co.,Ltd , https://www.whosalebreastpump.com