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

Determine the decimal equivalent of binary 1100 ?, The decimal equivalent o...

The decimal equivalent of (1100) 2   is ? Ans. (1100) 2 = (12) 10

How many ram chips are required for memory of 2048 bytes, How many 128 × 8 ...

How many 128 × 8 RAM chips are required to provide a memory capacity of 2048 bytes. Ans. Available here RAM chips = 128 x 8 Required the memory capacity    = 2048 x 8 No. of chip

Convert, haw to convert context free grammar to regular grammar

haw to convert context free grammar to regular grammar

Determine the nand gate, If  the input to T-flipflop is 100 Hz signal, the ...

If  the input to T-flipflop is 100 Hz signal, the final output of the three T-flipflops in cascade is ? Ans. The  final  output  of  the  three  T-flip-flops in cascade is 12

Html, discuss hypertext mark up language

discuss hypertext mark up language

binary division program for signed integer, The program division.c is avai...

The program division.c is available for download as part of this assignment. It is a binary division program which works for signed integers. It contains a function, div32, which d

Define about hyper-threading technology, Q. Define about Hyper-threading te...

Q. Define about Hyper-threading technology? Hyper-threading technology enables a single microprocessor to behave as two separate threaded processors to operating system and app

Develop a program which reads hexadecimal number, Q.  Develop a program, wh...

Q.  Develop a program, which reads Hexadecimal number from an input file & convert it into Octal, Binary, and Decimal. The O/P should be written to a file & displayed accordingly.

Addition NO-SIGNS to the Write statement, Suppressing the number signs (+/-...

Suppressing the number signs (+/-) is carried out using the addition NO-SIGNS to the Write statement. Statement is false.

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