DDR Full Form

It is the transfer of data both on the rising and falling edges if the clock signal .It is an advanced version of synchronous dynamic access memory that is SDRAM.In this it waits for the clock signal before responding to control inputs.DDR uses both Falling and rising clocks signal.It transfer data twice per clock cycle.DDR SDRAM is a common type of memory used as RAM for most every memory.

Definition

It is a computer memory that can transfer data twice as fast as the regular SDRAM chips .The DDR is simply the advanced version of SDRAM.The DDR memory can send and receive signals twice per cycle, that too specifically clock cycle .

The efficient operation of DDR SDRAM gives a great memory.

History

In the year 1970 came the DRAM that is the Dynamic Random Access Memory .It is not regulated by clock also it is not synchronised by any external influence . Further this posed a problem in organising the data so came the SDRAM that is synchronous and it synchronises with clock and hence creating predictable cycle .Being synchronous means that SDRAM and DDR before responding to control inputs and is linked with computer’s system bus.So it has a more complex  pattern of operation than other like DRAM.

SDRAM and DDR have speed in MHz than nanosecond.SDRAM is thus a first generation DRAM which is slower than the DDR.

Double data rate

RAM fetches data once per cycle but DDR fetches data twice per cycle .DDR has been used since 1990s and is commonly known as RAM.In laymen terms people call the RAM processor as DDR since it is widely used in CPU RAM.

DDR is not a flash memory as that present in the secure digital cards or as used in solid state drives.

The memory of DDR is volatile that means that everything goes off once the power is removed.This is one of the major disadvantages but on coming on to its plus points DDR transfers data at much faster rate than other memory product.Moreover the capacity of DDR is higher.

The DDR uses microprocessors to carry data between the CPU, the brain of the computer and the north bridge which is a chip in chipset .The pathway of transfer of data via microprocessors is known as the front- side bus .

DDR has a speed of at least 200MHz.It is also used for DDR SDRAM and Ultra – 3 SCSI.

Features or characteristics of DDR

• DDR is cheap 
• Offers double the transfer of data
• Consume less power than SDRAM models 
• Less heat is produced during Operation in comparison to SDRAM
• DDR uses 184 pin connector
• DDR and the new DDR 2 uses a 64 bit wide data bus 
• Newer versions DDR 2 andDDr 3 uses 240 pin dual inline memory modules
• Different versions are keyed differently
• Newer modules to improve the double pumping such as quad pumping are being used

Versions

In the coming years the DDR has improved and progressed from DDR to DDR2 and further with DDR 4 . The evolution is in terms of the requirement of low voltage supply and hence increased power saving capacity. .For example the DDR 2 operates at a voltage of 1.8 volts unlike the DDR with 2.6 volts .So there is a decrease in the operating voltage and power consumption . Further the latest versions have a higher speed

DDR also becomes denser since  more transistors are packed together while the DDR SDRAM is an integrated chip system .

Difference between SDRAM and DDR 

SDRAM the synchronous dynamic access memory transfer data once per clock cycle while DDR the Double data rate transfer data twice per clock cycle.Further the DDr uses both edges of the clock while thE SDRAM uses only one edge .

Difference between Quad data rate pumping and Double data rate

• Quad data rate pumping transfer data at four points as the name quad suggests.Being more advanced it transfers data at four bits of data per signal in clock cycle.Unlike DDR that transfers data at two points 
• Quad pumping operates at twice the frequency of that Double data rate

Conclusion

The improvement version in double data rate has proven to be an asset in the world if technology since it saves power and helps faster transmission of data with a great speed .The government should thus encourage this sector to get its full potential out .DDR and its improved version is thus the way forward for the tech driven 21st century that we live in today.