What is dynamic random access memory, Computer Engineering

Assignment Help:

Q. What is Dynamic Random Access Memory?

RAM technology is divided into 2 technologies: Static and dynamic. A dynamic RAM (DRAM) is made with cells which store data as charge on capacitors. Absence or presence of charge on capacitor is interpreted as binary 1 or 0. Since capacitors have a natural tendency to discharge, dynamic RAM needs periodic charge refreshing to maintain data storage. Term dynamic corresponds to this tendency of stored charge to leak away even with power continuously applied.

Figure below is a typical DRAM structure for an individual cell which stores one bit. The address line is activated when bit value from this cell is to be read or written.  Transistor acts as a switch which is closed (allowing current to flow) if a voltage is applied to address line and open (no current flows) if no voltage is present on address line.

2157_What is Dynamic Random Access Memory.png

For write operation a voltage signal is applied to bit line; a high voltage represents 1 and a low voltage represents 0.  A signal is then applied to address line allowing a charge to be transferred to capacitor. 

For read operation when address line is selected transistor turns on and charge stored on capacitor is fed out onto a bit line and to the sense amplifier. Sense amplifier compares capacitor voltage to a reference value and decides if cell contains logic 1 or logic 0.  The read out from cell discharges the capacitor that should be restored to complete operation. 

Even though the DRAM cell is used to store a single bit (0 or 1) it is necessary an analog device. Capacitor can store any charge value within a range. A threshold value determines whether charge is interpreted as 1 or 0.


Related Discussions:- What is dynamic random access memory

Specify the goals of parsing, Specify the goals of parsing. Goals: ...

Specify the goals of parsing. Goals: a. To check the validity of source string b. To agree on the syntactic structure of a source string. For invalid string this rep

Basic logic gates, Basic logic gates Introduce the basic logic gates i...

Basic logic gates Introduce the basic logic gates in terms of a) their function, b) their circuit symbol, c) their truth table and d) their equivalent in Boolean a

Illustrate lcd technology, Q. Illustrate LCD Technology? The technology...

Q. Illustrate LCD Technology? The technology behind LCD is known as Nematic Technology since the molecules of liquid crystals used are nematic which implies that rod-shaped. Th

Knowledge representation in artificial intelligence , Knowledge Representat...

Knowledge Representation: To recap, now we have some characterizations of Artificial Intelligence, so  when an Artificial Intelligence problem arises, you will enable  to put i

Explain about the term- reports, Explain about the term- Reports Repor...

Explain about the term- Reports Reports are produced as a result of questions like "how many times has a type of car broken down" or "which cities have the highest house price

Can we run dot.net in unix platform, Can we run DOT.NET in UNIX platform? ...

Can we run DOT.NET in UNIX platform? One of the drawbacks of using Visual Studio.NET and the .NET framework to develop applications has been the lack of cross-platform support

Explain the propagation delay characteristics for digital ic, Explain the ...

Explain the Propagation Delay characteristics for digital IC's. Ans: Propagation Delay: - The speed of a digital IC operation is given in terms of propagation delay ti

Explain physical characteristics of magnetic disk, Q. Explain Physical Char...

Q. Explain Physical Characteristics of magnetic disk? Figure below lists main features that differentiate among different types of magnetic disks. First head may either be fixe

Send a report to the printer, How to send a report to the printer instead o...

How to send a report to the printer instead of displaying it on the screen? We can send a report to the printer instead of displaying it on the screen.  To do this, use the key

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd