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Mi 5

Tech class

[Discussion] [Tech Class] Chapter 17: All About RAM

2017-06-22 03:10:37
17548 292

Hey Mi Fans,
In the last Tech Class you all are known about TWRP. In this Tech Class you will learn more about RAM, Types of RAM, How it works, etc.

So, let's get started!

What is RAM (Random Access Memory)?

As most of you would know RAM is Random Access Memory. It is faster memory compared to your permanent storage which includes your SD card internal and external. When your processor computes data it is faster to retrieve data required for processing from your RAM rather than to load it from your permanent storage which takes time. Also it is less taxing on the battery of your phone when your CPU retrieves data from RAM rather than from Storage.

How does RAM work in mobiles?

The RAM works quite different on your android phones than on your PC which most of us basic users are better acquainted with. The Apps that you download and install are first loaded in the RAM and then executed. Those Apps remain in the RAM after you are no longer using them and they have been shifted to background. The next time you use those apps they will be available for fast retrieval from RAM unless they have been removed. With continuous usage, the Apps that you use most frequently get placed on your RAM that is If you have enough RAM.

Type's Of RAM:
Basically RAM are of two types:
(i) Dynamic Ram

Dynamic random-access memory (DRAM) is a type of random-access memory that stores each bit of data in a separate capacitor within an integrated circuit.
DRAM is Volatile Memory (vs. Non Volatile Memory), since it loses its data quickly when power is removed. However, DRAM does exhibit limited data remanence.

(ii) Static RAM

Static random-access memory (static RAM or SRAM) is a type of semiconductor memory that uses bistable latching circuitry (flip-flop) to store each bit. SRAM exhibits data remanence, but it is still volatile in the conventional sense that data is eventually lost when the memory is not powered.
The term static differentiates SRAM from DRAM (dynamic random-access memory) which must be periodically refreshed. SRAM is faster and more expensive than DRAM; it is typically used for CPU cache while DRAM is used for main memory.

Some others RAM are EDO (Extended Data Output) RAM, SDRAM (Synchronous DRAMS), DDR-SDRAM (Double Data Rate – SDRAM), DDR-LPRAM (Double Data Rate - Low Power RAM), MDDR (Mobile DDR)

EDO (Extended Data Output) RAM: Extended Data Out Dynamic Random Access Memory, a type of DRAM that is faster than conventional DRAM. Unlike conventional DRAM which can only access one block of data at a time, EDO RAM can start fetching the next block of memory at the same time that it sends the previous block to the CPU.

● SDRAM (Synchronous DRAMS): SDRAM (synchronous DRAM) is a generic name for various kinds of dynamic random access memory (DRAM) that are synchronized with the clock speed that the microprocessor is optimized for. This tends to increase the number of instructions that the processor can perform in a given time.

● DDR-SDRAM (Double Data Rate – SDRAM): Double data rate synchronous dynamic random-access memory (DDR SDRAM) is a class of memory integrated circuits used in computers. DDRSDRAM, also called DDR1 SDRAM, has been superseded by DDR2 SDRAM, DDR3 SDRAM and DDR4 SDRAM.

● DDR-LPRAM (Double Data Rate - Low Power RAM):
Low-power DDR (sometimes, in hindsight, called LPDDR1) is a slightly modified form of DDR SDRAM, with several changes to reduce overall power consumption.

● MDDR (Mobile DDR): MDDR is an acronym that some enterprises use for Mobile DDR SDRAM, a type of memory used in some portable electronic devices, like mobile phones, handhelds, and digital audio players. Through techniques including reduced voltage supply and advanced refresh options, Mobile DDR can achieve greater power efficiency.

Mostly in mobile DDR-SDRAM or DDR-LPRAM Is used

What Is DDR?
DDR RAM stands for "Double Data Rate Random Access Memory."
"Double Data Rate" means that it can fetch data on both the up and the down cycles of the clock, unlike the previous versions of RAM which only fetched on one clock edge.
The original DDR RAM was, very simply, exactly like the old SD RAM but with the speed at which it could transfer data doubled by transferring on both clock edges.

DDR - LPRAM and DDR - SDRAM are of these types -
DDR-1, DDR-2, DDR-3, DDR-4

Difference Between DDR1,DDR2,DDR3,DDR4:
DDR2 RAM added a 2x clock multiplier to the module, which meant the bus clock running at the same speed as DDR RAM would be doubled, thus multiplying transfer speeds by 2 for the same bus speed.

DDR3 RAM replaces the 2x clock multiplier with a 4x clock multiplier, thus running at 4 times the memory transfer rate for the same bus speed as the original DDR RAM.

Additionally, DDR2 is capable of running at a lower voltage than DDR, and DDR3 is again capable of running at a lower voltage than DDR2 and DDR4 is more capable of running at a lower voltage than DDR3

A detailed graph about DDR-SDRAM and DDR-LPRAM:
RAM Bus Clock
Internal Rate
(Min Burst)
Transfer Rate
DDR1 100-200 100-200 2n 200-400 2.5/2.6
DDR2 200-533.33 100-266.67 4n 400-1066.67 1.8
DDR3 400-1066.67 100-266.67 8n 800-2133.33 1.5/1.35
DDR4 1066.67-2133.33 133.33-266.67 8n 2133.33-4266.67 1.05/1.2


RAM Bus Clock
Internal Rate
(Min Burst)
Transfer Rate
DDR1 200-266.67 200-266.67 2n 400-533.33 1.8
DDR2 400-533.33 200-266.67 4n 800-1066.67 1.2/1.8
DDR3 800-1066.67 200-266.67 8n 1600-2133.33 1.2/1.8
DDR4 1600-2133.33 200-266.67 16n 3200-4266.67 1.1/1.8

*Bus Clock :
The bus clock rate is the actual speed of your FSB(The FSB connects the processor  in your mobiles to the system memory).
**Internal Rate :
The internal clock rate is the frequency needed to match the external clock rate. So DDR types with larger data-depth require less internal transfers per second to match the external speed.
***Prefetch :
The gap between internal and external frequency is indeed bridged by prefetch mechanism.
****Transfer Rate :
It meams actually Data transfer rate of the devices.

Some FAQ Related RAM and Mobiles

What happens when my RAM is full?
Many users are worried by their RAM consumed rapidly. The Android operating system has been so designed as to use most of the RAM and leave certain amount for smooth functioning of the User Interface. You don’t have to be worried at all and need not go killing each application after use. Android will free the RAM when it needs to and it does so in a graceful way. It follows certain steps and protocols and won’t haphazardly kill your Apps just to free space. The unused RAM on your device is wasted RAM and more RAM you have more Apps you can run simultaneously

Will the Apps loaded in my RAM effect my battery performance?
Just a free app lying in the RAM does not consume your battery. If you are using an App like facebook with notifications on, then it will tax your battery, because it will be interacting with the server. Most Apps won’t affect your battery drastically but as our Android experience very well tells us Apps can’t be trusted. If you find an unexpected fall in your battery backup, go to the battery option in settings Menu or you can download a battery checker app and you can easily figure out the misbehaving app and kill it using the linked tutorial.
An App simply lying in the RAM is not a threat; more apps in the RAM will mean faster performance as processor won’t have to load them again from internal storage and as we have mentioned above retrieval from RAM is faster.

Will Increase in RAM make my phone fast?
Increase in RAM will definitely boost the performance as you can keep more apps in the RAM and they can be quickly and effectively loaded, however if you have a 512 MB RAM and you are using only 200 MB for Apps, then if you hypothetically, say, add 2 GB of RAM (not practically possible) then your performance won’t improve. If you are not using much of your RAM and your performance is not up to the mark, it is most probably due to some rogue App which is taxing your system resources un ethically. You can improve your performance by locating and killing that app using the linked tutorial.


The basic fundamental of the RAM, You need to know is  "The Apps that you download and install are first loaded in the RAM and then executed. Those Apps remain in the RAM after you are no longer using them and they have been shifted to background. The next time you use those apps they will be available for fast retrieval from RAM"

Credits: Google Images, Tech Blogs, All DT Mod and Members

Previous Tech Class Chapter:
Chapter 16 -All About TWRP
Chapter 15-All About CPU Cores
Chapter 14-All You Need To Know About Wi-Fi
Chapter 13-All About Kernal
Chapter 12-All About Rooting
Chapter 11-All About Network Bands
Chapter 10-PDAF and Its Difference With CDAF
Chapter 9-Megapixel and Photo Quality
Chapter 8-CPU Architecture,CPU,GPU
Chapter 7-Infrared Blaster
Chapter 6-Internet of Things & Mi Home
Chapter 5-All About Activity Tracker and Fitness Band
Chapter 4-All You Need To Know About Charging Cycle
Chapter 3-All You Need To Know About Augmented Reality
Chapter 2-All About Processor and Multi Core Processing
Chapter 1-Introduction to Smartphone Specification

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2017-06-22 03:10:37
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soumyajit_pal | from Redmi 3S


Powerful thread!
2017-06-28 02:41:24
Informative Thread, thanks for sharing
2017-06-28 02:01:06

Master Bunny

ANIL KUMAR VERMA | from Redmi Note 4


Good Information
2017-06-28 02:01:39

Master Bunny

Avneesh tiwari | from Redmi 4


2017-06-28 02:03:34

Master Bunny

Balaji##33 | from Redmi Note 4


nice info thanks for sharing
2017-06-28 02:07:52

Pro Bunny

Aman Bagoria | from Redmi 3S


nice information
2017-06-28 02:08:29

Advanced Bunny

Rider88 | from Redmi Note 4


Its very useful for us. Thanx for sharing this information.
2017-06-28 02:15:55

Advanced Bunny

Habibullah | from Redmi 4


Nice jankari
2017-06-28 02:16:06

Techie Team

A.Akbar | from mobile


Well explained.
2017-06-28 02:22:07

Pro Bunny

1579345813 | from Redmi Note 3


Nice theart
2017-06-28 02:22:49

Master Bunny

the_3pyro | from MI 4W


so many rams....
2017-06-28 02:22:56

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