Your Electronics Open Source

The ever decreasing scale in microelectronics
Ever since the beginning of the microelectronics era there has been an eternal quest to reduce the characteristic features on the devices: some devices are now in qualification states on the sub 40nm gate oxide range for an scheduled commercial release towards the end of the year, and there are a lot of efforts in the sub 30nm range. But Moore’s Law, as this continuous drive to reduce sizes has come to be called, applies not only to the dimensions on the silicon. It spreads down through the whole microelectronic supply chain, into pcb packages, system integration and final devices.

This blog describes my idea about integrating MMC/SDIO in embedded systems, including software in host controller and card controller running in SPI mode. Although I do not have full source code to demonstrate, theoretically it is realizable.
Flash Cards Everywhere
All kinds of flash cards are parts of our digital lives. They are used everywhere in mobiles, cameras, mp3s and DVD players. These cards are offering more storage memory space in much lower price. Technically these cards are quite mature to be integrated into many devices. However the engineers can not find suitable open source stack solutions because of legal issues from the corresponding flash card associations.

I first learned of the STM32 Primer at a technical seminar presented by STMicroelectronics. The STM32 Primer is designed to provide a complete toolset for STM32 that is fun and easy to use. Give it a try and learn about the features of the STM32 and the powerful ARM Cortex™-M3 core.

USB-Stick as development systems.

It's the fad of the moment and, we, as designers, do love these Gadgets!
But what they are? Are Development Tools in USB Stick format simply toys or are they offering a complete and reliable debug system?
Surely the latter, because the capability (some of them have an ARM on board) and the versatility make a quality product highly useful for the developers. Some time ago I had the opportunity to "test" the Texas Instruments' Stick USB, the Ez430, related to the MSP430 Low Power Microcontroller, and I have to say that this "Gadget" (please note the quotes) surprised me, for its capabilities and easy of use. After 10 minutes I was already in step_by_step debug with my first application on Stick! (Ok, I did flashed a LED under interrupt while I had controlled the inputs in polling with debounce software, but the start-up times were reduced to a few minutes!!! )
Also, the really low costs of these Development Tools (I will not call them gadget anymore) allows you to evaluate any system before you start to design ..... starting from $ 10 and almost none of the presented Tools exceeds 50$
As far as I remember, TI with MSP430 was the first to launch this "fashion", and now the market is full of these Development Sticks, so I decided to see which new micros we can play ...(Ooops!) work with , to evaluate and then design, develop and go into massive production.
(The correction was necessary, otherwise, distributors and representatives will not give us any more Stick )

by Mauro Ceresa, [Assipe] , Future Electronics
Tools and information to simplify designing products based on power LEDs.

In the myriad of parameters and curves that characterise the performance of a LED, it is necessary to define the set points from which the other major features can be gleaned, to obtain the final result: the real efficiency and reliability of our application.

By Editorial Staff [DESIGN IN]

The LED using, in lighting applications, is becoming more and more attractive and the possibility of using the powerline directly, as a source of power supply, is becoming more and more interesting. Moreover, if the circuital solution allows a compact implementation that can be placed in the same volume of a standard lamp screw, it becomes more interesting.

by Franco Musiari [ Assipe ]
Efficacy, power and costs of high brightness LEDs have got levels that make them an attractive solution in many lighting system applications.

The luminous efficacy of a light source is the ratio between the emitted luminous flux and the amount of the absorbed energy to transmit it. It is expressed in lumen/watt (lm/W). The lumen, the measure unit of the luminous flux, is equal to the luminous flux detected in a solid angle of one steradian and emitted towards all directions from a source with a luminous intensity of 1 candle. (the steradian –sr symbol- is the SI unit of solid angle and it is defined as " the solid angle subtended at the center of a sphere of radius r by a portion of the surface of the sphere having an area r ²". Since the area of the sphere is 4πr², as a consequence the solid angle subtended by the whole sphere is equal to 4π sr).

The Ministry Information Industry (MII) of China enforced all mobile phone manufacturers to comply with new issued standard for phone charger interface, which is called YD/T 1591-2006 mobile phone charger and interface requirement and testing method. Before launching this standard, every mobile phone manufacturer has own power adapter interface with different electrical and physical specifications. Due to business and technical reasons, some vendors even offer different power adapters for same brand! This standard unifies the AC/DC power adapter interface with standard USB type A output on 5V DC, therefore new mobile phones from different vendors can share common adapters or be charged with standard PC USB port. The Mobile users can just carry one USB cable and phones on the go, since the USB port is available anywhere. It is anticipated that this approach can reduce power adapters in retail package, and reduce overall BOM cost and the pollution with the abandoned mobile phones.

I am Qprox QUANTUM consultant and Design Partner Microchip Technology, but now I have decided!
In the next project I'll use a Cypress Semiconductor product! Why?
Because Cypress is performant... as the rest of its employees!

by Franco Musiari [ DESIGN IN ]
Buck Regulators
This is the simplest topology - see Fig. 5 – and can directly replace the linear regulators previously described. The control circuit drives a transistor alternately in conduction status and interdiction status. During the conduction status the current flows from VIN to the diode (green dotted line on Fig. 5) and the energy initially associated to delta between VIN and the voltage fall on the LED, on the transistor and on RS is stored in the inductance. At the increasing of the stored energy in the magnetic circuit, the resistance decreases to the passage of the current, current that grows until the controller, that measures it on RS, does not drive the transistor to the interdiction status.

by Franco Musiari [ DESIGN IN ]
Driving the power LED depends on the application setting and it is not so trivial as it might appear.

The LEDs (Light Emitting Diode) are diodes whose basic characteristic is the ability to emit light when they are passed through a current that flows from P to N region. At each recombination between the charge carriers (electrons and holes), on PN junction region, a photo emission is generated, and the total quantity of emitted photons, and therefore the light intensity, is proportional to the current intensity that passes through them. The emitted light has a spectrum – wavelengths distribution – that is defined according to the materials used in the realization of the diode PN junction, although it partially depends on the current intensity and on the junction temperature. The most common materials, used in LEDs production, are those belonging to the III° and V° group of the elements periodic table:

Texas Instruments' Bill Klein Signal Chain Articles. Given the interest it has provoked the introductive article on "The MIDAS Touch for Signal Chain" , these articles are for the deepening the argument, proposing the presentation of Bill Klein in text format and then introduce a series of articles, written in parallel with Bill and in collaboration with Farnell on "signal chain", already known as MIDAS. So articles about Mixed_signal, Interface, Data_conversion, Amplification and Sensors will be published in the coming days.

A lot of users have the experience of virtual machines. These VMs are quite useful for developers who have to working on multiple OS platforms. There are many VMs running on embedded microcontrollers, too. These embedded VMs are dedicated for specific purpose. A lot of embedded applications leverage them to reduce system complexity, memory usage, and depoly the custom design. It sounds incorrect, since running VM requires extra resource of embedded microcontroller, and demands extra programming effort, either. However embedded VM indeed can help developers to achieve those goals.

By John Isaac, Mentor Graphics [ Courtesy of Assipe ]
In today’s competitive electronics industry, getting to market ahead of the competition can mean the difference between a successful product and one that misses its market window. Design cycle time plays a big part in determining a product launch schedule and the PCB layout portion of this process often is called upon to make up for early design phase schedule slips. One designer and one computer at a time can be a limiting factor.
Traditionally, designers are pulled in from other projects to assist with meeting deadlines, usually by adopting shift-work routines or physically splitting the design into multiple pieces. Both methods incur significant overhead costs that tend to negate the advantage of design collaboration. Partitioning the design into pieces and having designers work separately on each piece can help improve the situation. But putting that design database back together is a tedious and error-prone task.

Your News Open Source is the newborn from the Your Electronics Open Source family. Your News Open Source is a site dedicated to the news of the electronics world. Each news is framed in Topics (RF, Analogs, Digitals, Passives o General) and with tags. If you want to read the whole news you can do it through the link which is located immediately after it, or going into the bottom of the page where you can find all producers from where Your News Open Source takes news. If some tag intrigue you (you find the entire list at the bottom of the page in the section Tags Cloud) you have to click on it and will appear all the news that belong to that tag. If you want to read the news on a particular category (RF, Analogs, Digitals, Passives or General) click on the taskbar categories (Topics).