August 30, 2014

Automatic Analog Layout Generation

Design Environment: Mentor Graphics
Language: Perl
OS: Unix

An algorithm is developed for designing an automatic Op-amp layout generation by using scripting language. The layout of the two-stage Op-amp will automatically draw out in the Mentor Graphics IC station by inserting the essential data. The main challenges are design a common-centroid layout template, and how to route each transistor automatically without violating the DRC (Design Rule Check).

The algorithm invokes DRC file, using circuit netlist information to generate circuit layout automatically with a common-centroid layout template.

Transistor Sizing Methodology for Low Noise Charge Sensitive Amplifier With Input Transistor Working in Moderate Inversion


July 12, 2014

Sophisticated radiation detector designed for broad public use

07/10/2014
CORVALLIS, Ore. – Nuclear engineers at Oregon State University have developed a small, portable and  inexpensive radiation detection device that should help people all over the world better understand the radiation around them, its type and intensity, and whether or not it poses a health risk.
The device was developed in part due to public demand following the nuclear incident in Fukushima, Japan, in 2011, when many regional residents were unsure what level of radiation they were being exposed to and whether their homes, food, environment and drinking water were safe.
Devices that could provide that type of information were costly and not readily available to the general public, and experts realized there was a demand for improved systems that could provide convenient, accurate information at a low cost. The new system should eventually be available for less than $150.
Findings on the new technology were just published in Nuclear Instruments and Methods in Physics Research, a professional journal. The systems are not yet available for commercial sale.
Beyond the extremely rare occasion of a radiological or nuclear incident, the new technology may also help interested consumers learn more about the world of radiation surrounding us, the constant exposure they receive – everything from a concrete wall to the air we breathe, soils around us or a granite kitchen counter top – and how to understand routine radiation exposure as a part of normal life.
“With a device such as this, people will be better able to understand and examine the environment in which they live,” said Abi Farsoni, an associate professor of nuclear engineering in the OSU College of Engineering. “Radiation is a natural part of our lives that many people don’t understand, but in some cases there’s also a need to measure it accurately in case something could be a health concern. This technology will accomplish both those goals.”
Of some interest, the researchers said, is that the technology being used in the new device provides measurements of radiation that are not only less expensive but also more efficient and accurate than many existing technologies that cost far more. Because of that, the system may find use not just by consumers but in laboratories and industries around the world that deal with radioactive material. This could include scientific research, medical treatments, emergency response, nuclear power plants or industrial needs.
The system is a miniaturized gamma ray spectrometer, which means it can measure not only the intensity of radiation but also identify the type of radionuclide that is creating it. Such a system is far more sophisticated than old-fashioned “Geiger counters” that provide only minimal information about the presence and level of radioactivity.
“The incident at Fukushima made us realize that many people wanted, but were not able to afford, a simple technology to tell them if their environment, food or water was safe,” Farsoni said. “This portable system, smaller than a golf ball, can do that, and it will also have wireless connectivity so it could be used remotely, or connected to the Internet.”
The system combines digital electronics with a fairly new type of “scintillation detector” that gives it the virtues of small size, durability, operation at room temperature, good energy resolution, low power consumption and light weight, while being able to measure radiation levels and identify the radionuclides producing them.
Various models may be developed for different needs, researchers said, one of which might be the ability to measure radon gas and check homes with possible concerns for that type of radiation exposure, which can sometimes come from soils, rocks, concrete walls or foundations.
“There are a lot of misconceptions by many people about radioactivity and natural background radiation, and technology of this type may help address some of those issues,” Farsoni said. “Sometimes, there are also real concerns, and the device will be able to identify them. And of some importance to us, we want the technology to be very simple and affordable so anyone can obtain and use it.”
The new device, called a “MiniSpec,” will ultimately be commercialized after final development is completed, researchers said.

Source:http://oregonstate.edu/ua/ncs/archives/2014/jul/sophisticated-radiation-detector-designed-broad-public-use

May 25, 2014

Electronics circuit diagram/schematic drawing softwares list

electronic schematic drawing software
This article is an attempt to list out all available softwares for circuit drawing. I have taken into consideration many criteria before making this list. You know there are free softwares, paid softwares, sharewares and there will be variations in quality of softwares, user friendliness, complexities etc. I have tried to include as many software as possible. For instance if there is a tool that helps only in basic drawing but is really user friendly so that a beginner can draw electronics circuit diagram, then I would consider adding that particular software. Circuit drawing or electronic schematic drawing is not a hard to learn stuff, you can make it better with practice. Well there are some standard practices that you have to keep in mind while you draw. We will write an article regarding the standard practices to follow while drawing circuit diagrams.
Lets list out free circuit diagram drawing softwares first.

Free circuit drawing softwares list:-

PCB123 – This is a free circuit drawing software from Sunstone. You can do almost all your needs from design to build using PCB 123. PCB123 provides 500,000 parts with great search functionality to access all the parts while drawing. Datasheets of select parts are available. The interesting feature of this software is “real time” search for availability of parts from Digi-Key. Well, give it a try and give your opinions. After all it’s a free software from a reputed company like Sunstone.
Xcircuit - is a free schematic drawing software from OpenCircuit designs, which is made for Unix/Linux environment. You can use this software on Windows if you have the X-server running or Windows API. This open source project is aimed at developing output schematics that are of high quality, ready for instant publication. Many versions of the software are available. You have to go through the tutorial thoroughly before you start using it.
TinyCad - is a schematic drawing software for Windows from SourceForge. It supports circuit drawing, layout developing and circuit simulation. It is available for free download.
Dia - Dia is a basic drawing software suitable for drawing block diagrams. They provide access to some basic and important components too. This software is only for a beginner or a new entrant in the electronics circuit drawing arena. I consider this software good for drawing block diagrams.Software has a GPL license and is made for Mac and Linux. I don’t know if they have a Windows version.
SmartDrawFree software for drawing electronics schematics. This software is from SmartDraw LLC which develops high end drawing softwares and CAD softwares. The free version is a tool for promoting their paid versions. So you may not expect great/advanced features in the free version.
Pspice – Student Version - You all know about Pspice – the simulation software. Follow that link to get a free student version of the Pspice.
ProfiCAD - is a free, basic tool for drawing. I haven’t used this yet, well try out and tell me.
Solve Elec - is a free software for Windows and Mac.

Paid/Enterprise Softwares:

Tina – Tina is an affordable solution for small industries and freelancers. Facilitates circuit drawing, layout developments, simulation and other features. Real time testing of circuits is another notable feature.
Orcada highly popular software from Cadence for circuit drawing, layout development and simulation.
CadSoft Eagle - another high quality PCB design software. Easily Applicable Graphical Layout Editor is the abbreviation of EAGLE.
LTSpice - is a simulation software from Linear. Schematic development, spice simulation, waveform viewer and many other features.
Altera - has a lot of softwares for your various needs. They have softwares for Embedded design (NIOS II), DSP design software (DSP Builder).  For logic design they have Quartus II and ModelSim.
PCB Pool - They don’t provide any softwares. This link is in fact a list of softwares for PCB design.
So I guess I have compiled a good enough list of circuit drawing softwares, which can be used for electronics circuit drawing, schematic layout drawing, wiring diagram drawing etc. I will add more softwares to this list if you can suggest it through our comments section.

Wafer Fab

1. The MOSIS Service:
http://www.mosis.com

2. TSMC (Taiwan Semiconductor Manufacturing Company) :
http://www.tsmc.com/english/default.htm

3. Silterra, Malaysia
http://www.silterra.com

References for CMOS Analog Circuit Design

If you can review the references in the order well, then you’re on the right way…
1) Design of Analog CMOS Integrated Circuits, by Behzad Razavi
2) CMOS Analog Circuit Design, by Phillip E. Allen & Douglas R. Holberg
3) CMOS Circuit Design, Layout, and Simulation, by R. Jacob Baker

Good Op-Amp Web Sites

www.linear-tech.com
www.national.com
www.burr-brown.com
www.maxim-ic.com
www.intersil.com

May 24, 2014