Hello there. It's high time for us to continue on the remaining component that is present on our smartphones which gives it the functionality that it possess. Our smartphones are mini- computer that possess all the components embedded on small chips which is planted inside the phone.

For  previous articles where the foundation for this post was been laid, check here for [article one](https://steemit.com/stemng/@steep2308/system-on-chips-the-components-on-your-smartphone-and-ipad) and the other second one which is recent is this [one](https://steemit.com/stemng/@steep2308/system-on-chips-how-the-memory-on-your-smartphone-operate). So far so good, I have discussed, some of those component as you will find it in the embedded link.

**Let's continue with Northbridge**
This is one of the major part of the computer present both on personal computer and also integrated on SoC. It is responsible for communication with the Central Processing Unit (CPU) on computer and coordinate the relation among several part of the computer including memory (much discussed in the last article), the peripheral component interconnect bus, and some others. With the frontside bus, the communication between the Northbridge and the processor is established. It act as a connecting point for the communication between the **southbridge chip** and the Central Processing Unit, Random Access Memory and the graphic controller (GC). On the System on Chips (SoCs), Northbridge is just a single **ic** just as it's a single chip on modern day computer been completely different from early computers which had three different chips acting as the Northbridge chips.

![Motherboard_diagram.svg.png](https://ipfs.busy.org/ipfs/QmUFM8DGpJx1EP4o7Hjs5ZhmCE67b2JdQcDkFpBixVrY8Z)


[Northbridge and southbridge layout:By Original: Gribeco at French WikipediaDerivative work: , CC BY-SA 3.0,](https://commons.wikimedia.org/w/index.php?curid=3789066)
Since we are talking about System on Chips, we should focus on the technology in Vogue. The Northbridge has now been integrated into the Central Processing Unit [*die*](https://en.m.wikipedia.org/wiki/Die_(integrated_circuit))  Such include the [**Intel Sandy Bridge**](https://en.m.wikipedia.org/wiki/Sandy_Bridge) , a 64-bit microprocessor [Product of Advanced Micro device(AMD)]. The design of this 64-bit micro processor is purposed to function as the **central processing unit and graphic processing unit** on a single die. 

<div class="pull-left"><center><img src="https://s7.postimg.cc/kkztz6ofv/1024px-_Pentiumpro_moshen.jpg"/><br/><em><a href="https://commons.wikimedia.org/w/index.php?curid=2262471"><sup>   A typical die   CC BY-SA 2.5,  </sup></a></em></center></div>

Since the Northbridge is responsible for connecting the central processing unit to other devices that operate at a very high speed as earlier discussed, the southbridge which doesn't have direct connection with the central processing unit connect to peripheral buses of lower- speed. 

The Northbridge is accountable on how system generally is **overclocked**. This term overclocked is used when our devices hardware function at a faster rate than how the manufacturer had design it. When demand for the operation of the device is high such as downloading a high quality video or streaming live video for a long period of time, or charging and using it, the operational stability may be compromised. The power consumption increased and more heat is generated, at this point, your device needs to undergo gradual and not rapid cooling such as placing it inside a coolant.



**The Southbridge**
The southbridge in contrast to the Northbridge is connected to the other  components having slow capabilities on the chips and on the intel board containing the northbridge/southbridge. It is south to the Northbridge and is not directly connected to the Central Processing Unit. It is responsible for handling the output and input controller hub (though as found on the Intel motherboard architecture.) It connects the low speed essential component below it to the north path of the board. It is connected by the Northbridge to the CPU for data transmission from the less speed component directly under it.


Advance in technology with the advent of more relevant design made southbridge to give room for the Platform Controller Hub (PCH). 

<div class="pull-right"><center><img src="https://s31.postimg.cc/daovm5n7f/Intel_DH82_H81_PCH.jpg"/><br/><em><a href="https://commons.wikimedia.org/w/index.php?curid=47417190
  "><sup> PCH:CC BY-SA 4.0,</sup></a></em></center></div>


Every features and functionality of southbridge are now been taken care of by the architectural design which make the Platform Controller Hub unique in it own sense. The  Platform Controller Hub connection is direct to the Central Processing Unit (CPU) through the Direct Media Interface. This PCH regulate  data flow and corroborate the functions known with Northbridge and southbridge. Some of these functi Ions now been performed by Platform Controller Hub  are the **clocking** ( normal time as we have it on system), [flexible display interphase](https://en.m.wikipedia.org/wiki/Flexible_Display_Interface). The information inlet and outlet function of southbridge is on the PCH .

Functions been performed by Northbridge is now transferred to the Central Processing Unit, while the functions of southbridge is now taken over by Platform Controller Hub. Though, those functions are primarily attributed to the two bridge but are now found to be embedded in new technology of system on Chips design being used by smartphones manufacturers. Let check one out here

**Qualcomm Snapdragon S<sub>4</sub>SoC**

This is a typical System on Chip design for use by semiconductor manufacturer. It consist of several component which made up the SoC functionality. Embedded on it includes the central processing unit with multiple core (*this core is like a hand which you can use to do many things at the same time*).  

<div class="pull-left"><center><img src="https://s31.postimg.cc/w84yiccuz/800px-_LG_P710_Optimus_L7_II_-_Qualcomm_MSM8225_on_main_printed_c.jpg "/><br/><em><a href="https://commons.wikimedia.org/w/index.php?curid=53628720"><sup>Qualcomm Snapdragon: CC BY-SA 4.0,</sup></a></em></center></div>
The core functions by performing command or instructions from the central processing unit. The chip also has on it, a graphics processing unit which I explained in the first part of this series, that it is responsible for the 3 dimensions games (3D games). Also on it is a wireless modem. The wireless modem embedded on the chip is responsible for our smartphones connecting or allowing *wi-fi* device. When you check your mobile devices mostly from setting>mobile network> WAP., you see acronym like *WAP* which stand for Wireless Access Point. The Chips contain some other components which makes the mobile phone camera , the Global Positioning System (GPS) to function without any hitch. Manufacturers of  different smartphones using mobile operating software such as Android and windows software use this chip for there product. 

<hr>


This Chip coming with different categories makes your smartphones to give you more function. Take for instance, smartphones that can provide 4G LTE (Fourth generation Long-term-Evolution) connection has a higher category 4G LTE base-band ( primary/ initial frequency of communication signal transmitted prior to conversation) on it's system on chip and some other components which improve such phone interaction with the air. Before the category 3 just discussed, any 4G LTE connections on mobile device is on two basebands. One of the baseband is for the 4G LTE connections while the other baseband is for voice using 2G data. So in such case, two baseband is responsible for the phone connectivity, one for internet connection while the other is for end to end voice call.

One other advantage of 4G  LTE smartphone is that internet browsing on such phone becomes easier, you can connect on it for video conference and easily play your game. With it, mobile hotspot can be enable on it for several other devices close to eight.

With the technology of the Snapdragon S4 processor, both modem baseband and the application processor  are on one chip and this translate to good power conservation and good performance. This modem can switch from 4G to 3G in case the LTE is down. The Snapdragon S4 processor employed a 28nm technology for it production which give room for number of transistors to increase and improve efficiency. It also possess a technology that can shut down the smartphone containing it when power has been discharged beyond permissible limit.



#### Summary
The Northbridge and the Southbridge are part of operating system were on Intel chips before  but have their function incorporated with new technology which still maintain the function of the two bridge in terms of data transmission.

Southbridge is replaced with Platform Controller Hub (PCH) and the Northbridge is integrated into the Central Processing Unit die.

Qualcomm Snapdragon S<sub>4</sub>SoC, is a new SoC which makes new smartphone to operate optimally with good battery life, and efficient internet surfing.

*Thanks for stopping by, please endeavor to drop your comment if you find this write up educative*




### REFERENCES
[Techtarget.com/definition/Northbridge](https://whatis.techtarget.com/definition/Northbridge)

[Computerhope.com/jargon/n/northbri.](https://www.computerhope.com/jargon/n/northbri.htm)

[Wiki/doku.php/doc/appunti/hardware/chipset](https://www.rigacci.org/wiki/doku.php/doc/appunti/hardware/chipset)

[Makeuseof.com/tag/iphone-ipad-getting-hot-heres-fix](https://www.makeuseof.com/tag/iphone-ipad-getting-hot-heres-fix/)

[Wikipedia.org/wiki/Qualcomm_Snapdragon](https://en.m.wikipedia.org/wiki/Qualcomm_Snapdragon)

[Anandtech.com/show/4940/qualcomm-new-snapdragon-s4](https://www.anandtech.com/show/4940/qualcomm-new-snapdragon-s4-msm8960-krait-architecture/4)

[What-integrating-4g-lte-modem-means-snapdragon-s4-processor-and-battery-life](https://www.qualcomm.com/news/onq/2012/06/20/what-integrating-4g-lte-modem-means-snapdragon-s4-processor-and-battery-life)