VLSI

LSI LOGIC -LSI Corporation is a leading provider of innovative silicon, systems and software technologies that enable products which seamlessly bring people, information and digital content together. Th a broad portfolio of capabilities and services including custom and standard product ICs, adapters, systems and software that are trusted by the world's best known brands to power leading solutions in the storage and networking markets. (www.lsi.com)

eInfoChips eInfochips is a technology design services & solutions company offering IPs & services in Software Products & Applications, Embedded System and ASIC/FPGA since 1994.(www.einfochips.com)

ConexantConexant Systems, Inc. (NASDAQ: CNXT) is a leading provider of solutions for imaging, audio, embedded modem, and video surveillance applications – areas where the company has established leadership positions. (www.conexant.co.in)

Sasken
With over 1500+ man years of experience in the VLSI space, Sasken delivers ASIC services and FPGA services to it’s customers in the Wireless, Communications, Consumer, Automotive, Networking & Defense domains.

http://www.sasken.com/services/ASIC_design_services.html

Tensilica (www.tensilica.com)
Tensilica is a fast growing, pre-IPO, venture-backed company focused on providing the ultimate in application specific microprocessor solutions for use in today's high volume embedded systems. .http://www.tensilica.com/company/careers.htm

nVidia I dont know whether any VLSI design goes there,You can go through following links (www.nvidia.co.in/page/home.html).

(www.nvidia.in/object/india_pune.html).

Wipro I dont got much info about this in VLSI..(www.wipro.com).

Wednesday, April 21, 2010

MOSFET as Switch

The MOSFET can be used as a switch as in figure show.Under the normal DC conditions ,the gate of MOSFET doesn't draws the current.Figure two shows the small signal resistance of the switches. So the Transmission gates are good as switch because at both conditions they provide strong VDD because of PMOS and strong zero because of NMOS {about strong zero and stron 1,refer link1}.

Limitations:
1)Charge Injection2)Clock(or capacitive) feed-through.
3)KT/C noise

We will see each of then in slight details
1)Charge Injection:The figure below shows the typical NMOS charge injection.When MOSFET is on ,due to small VDS there is small charge Q'c at the channel ..So when the MOS goes off ,the charge is distributed on both sides through source and drain i.e. towards the capacitor and tto the Vin ,but as all Vin source has low impedence the charge has no effect on Vin but it changes the voltage across CLoad .
There are lot many researches going on ,it is seen that if clock is very fast (turns off fast) the charge is equally distributed on both sides of the MOS. So we get 50% at C load side.
if clock makes slow transition all the charge could be absorbed at input.

We have Q=CV ,The total charge across the channel is given by Qch = WL*Cox(Vgs -Vth).
Where WL is the area of the channel.

Characterizing charge Injection
Change in the voltage across the load (if NMOS) is given by

Where Vdd-Vin =Vgs, Cox is the gate capacitance per unit area . Divide by 2 because 50 %.So in above euation ,you can see that the change in voltage across Cload is nonlinear with respect to Vin due to the threshold voltage.

In sampled-data systems, charge injection will result in non-linearity errors. So it should be obvious here that charge injection effects should be minimized as much as possible.

The sampled output is given by Vout=Vin-Delta(Vout).
The error for the NMOS switch appears as a "negative pedestal" at the output..

I am slight Busy ...have LOt in my mind but not the time to upload ,put jpeg files ..etc ...I will put everythin one by one in detail soon

Thursday, February 4, 2010

What basics are needed for vlsi

When u Think of vlsi ,the first picture comes to mind is

This may not be the same picture ..but every body thinks of designing chip…Buta in real fact we have to deal with coding of its parts…not total by alone….

For you to study , and make the carreer in feild of VLSI …U must have an basic knowledge of electronics ,as well as programming expierience at a basic level…

•At start of my first year in MS VLSI …i got the difficulty with learning of C language where the staff assumes that u have already knowledge of C…
Hence here I am giving the list of C books and the links within two days so that U can learn C from the basics …
U can download all the e books ….
1)Sam’s Teach Yourself C in 24 hrs
2)let us c By yashwant kanetkar..
3)C for dummies
4)C programming for absolute begginers….

After u have overall general knowledge of C you can look forward for solving more complex programs and make a good hand in C……

In VLSI it is basically needed since some of the codes of SOC (system on chip)etc u have to use C/C++
hence better to learn at starting….

•The second need is u must have a knowledge of electronics basis adout digital sytems/design and also of analog electronics…Analog electronics is not much needed…
Here I said you need basics of digital electronics means about adders/subtractors/logic families/gates/shift registers etc etc…
Secondly analog is not needed much means basically most part of VLSI deals with the GATE level having two states 0 and 1 or high/low….But when the design is at transistor level U need to know about transistors,BJT,MOSFET,CMOS etc etc….

Here For above knowledge I will recommend the following books ……
1)Digital design by Morris Mano
2)An engineering approach to digital design by Flethcer

I will post the links soon and the details of what basics You need to study from above books..for entering into feild of vlsi……

VLSI

Monday, April 26, 2010

VLSI COMPANIES

Wednesday, April 21, 2010

MOSFET as Switch

Thursday, February 4, 2010

What basics are needed for vlsi

Follow Our Blog

Categories

Blog Archive