E-infosl

Oct 1, 2012

Tracing down a noise problem – an interesting story

Tracing down a noise problem – an interesting story:

Gerard Fonte writes:

My client, a small manufacturer, was having a noise problem with a new batch of 1500V-dc supplies.
It had been a while since the company manufactured this product. The original engineer was long gone, and the only documentation was a schematic. The approach was a straightforward closed-loop design. An op amp controlled an oscillator that used a step-up transformer to create the high voltage, which the system rectified and filtered into dc. A small part of the output voltage fed back into the inverting input of the op amp as an error signal to adjust the oscillator frequency when necessary. The noninverting input was grounded.

Tracing down a noise problem – an interesting story - [Link]

Computer Precision for Power Tools

Computer Precision for Power Tools:

Computer Precision for Power Tools @ NYTimes.com – [via]

WOODWORKING is a tricky skill to master. Students learn to measure carefully before they reach for a saw, and to cut as true to the design as hand and eye allow. But, even so, precise cutting is a painstaking job, full of pitfalls and mismatched moldings.
Alec Rivers, a Ph.D. student at M.I.T., guides a cutting tool through wood by watching a computer screen.
Now computers and their tireless calculations may bolster the skills of many people who want to create well-cut picture frames, inlays or furniture but lack the dexterity.
Alec Rivers, a Ph.D. student at the Massachusetts Institute of Technology, and colleagues have created a prototype for a compact, computerized addition to power tools that automatically performs precision measuring and cutting.
The system, which has a tiny camera, motors and a video screen, takes part of the pain out of woodworking, by using what Mr. Rivers calls “tool GPS.”

Computer Precision for Power Tools - [Link]

Random posts

Better PCBs in Eagle

Better PCBs in Eagle:

Follow SparkFun recommendations for a better PCB. Nate writes:

We are constantly pushing ourselves for better printed circuit boards (PCB). One thing we’ve learned is that PCB fab houses (such as Advanced Circuits, BatchPCB, PCB123, Gold Phoenix, Bare Bones PCB, anyone really) have a very hard job to do. Creating a PCB is not an easy task and there are many ways for a fab house to mess it up. Unfortunately, fab houses tend to spend less time on prototypes than on production runs. Therefore, we try to design products and PCBs for ‘manufacturability’. This tutorial will show you how to minimize the number of ways the fab house can screw up a PCB.
We’ve messed up piles of PCBs over the years. We want to share with you some of the DFM (design for manufacture) rules and tricks and tips we’ve learned to get a good PCB, every time. If you’re creating a prototype PCB, we highly recommend you use these rules to increase the chances that your proto will work!

Better PCBs in Eagle - [Link]

Favorite diodes 1N4148 -THT but also SMT

Favorite diodes 1N4148 -THT but also SMT:

SMT components are still more used even in small production batches. That´s why in our portfolio, many components can be found in both versions – THT (through-hole technology) and also SMT.
As the praxis has shown, both Technologies have their stable place in the production of electronics. This is also confirmed by a known fact, that the highest density of components on a single-sided PCB can be reached by a combination of SMT and THT components, when the THT components on the rear side also act as „PCB tracks“.
To many components, which we have in both SMT and THT version, we incorporated a well-known favorite diode 1N4148 in an SMT sod123 package – 1N4148W. It is a universal switching (small signal) diode with a small PN junction capacitancy, thus suitable even for fast circuits. Small leakage current ensures a minimum influence of surrounding circuitry, that´s why the 1N4148 is often used also as a protective diode for protection of digital circuits inputs. Next time, when you´ll design a device with a 1N4148, try to consider, whether an SMT version wouldn´t suit better to you – 1N4148W, LL4148 (miniMelf), TS4148 or other versions.

Favorite diodes 1N4148 -THT but also SMT - [Link]

IKEA SMS lamp with GSM shield

IKEA SMS lamp with GSM shield:

open-electronics.org writes:

We create a lamp controlled by SMS using a GSM shield, a RGB shield and a Arduino UNO. Due to the simplicity of these boards, simply plug one over the other and connect a strip led to have a lighting effect. Then sending normal text messages from any phone, you can turn on and choose the color to set.

IKEA SMS lamp with GSM shield - [Link]

Electronics that Flex and Stretch like Skin

Electronics that Flex and Stretch like Skin:

Research laboratory Imec has announced that it has integrated an ultra-thin, flexible chip with bendable and stretchable interconnects into a package that adapts dynamically to curving and bending surfaces. The resulting circuitry can be embedded in medical and lifestyle applications where user comfort and unobtrusiveness is key, such as wearable health monitors or smart clothing.
For the demonstration, the researchers thinned a commercially available microcontroller down to 30µm, preserving the electrical performance and functionality. This die was then embedded in a slim polyimide package (40-50µm thick). Next, this ultrathin chip was integrated with stretchable electrical wiring. These were realized by patterning polyimide-supported meandering horseshoe-shaped wires, a technology developed and optimized at the lab. Last, the package is embedded in an elastomeric substrate, e.g. polydimethylsiloxane (PDMS). In this substrate, the conductors behave as two dimensional springs, enabling greater flexibility while preserving conductivity. [via]
Electronics that Flex and Stretch like Skin - [Link]

Electronics that Flex and Stretch like Skin

Electronics that Flex and Stretch like Skin:

LED Heart PWM Fading

LED Heart PWM Fading:

The concept for this small birthday present was to create a small heart shape with red LEDs and then to draw a heart shape underneath it on the PCB as a backdrop. Then a small processor was added to control the heart shape of LEDs for both fade and pattern control. The method of control that we use (PWM) allows us to save precious battery life, control the exact brightness of each specific LED and create this tiny but awesome project.
LED Heart PWM Fading – [Link]

TPS53014 – Single Synchronous Step-Down Controller for Low Voltage Power Rails

TPS53014 – Single Synchronous Step-Down Controller for Low Voltage Power Rails:

The TPS53014 is a single, adaptive on-time D-CAP2 mode synchronous buck controller. The TPS53014 enables system designers to complete the suite of various end equipment’s power bus regulators with cost effective low external component count and low standby current solution. [...]
The device provides convenient and efficient operation with input voltages from 4.5 V to 28 V and output voltage from 0.77 V to 7.0 V.
TPS53014 – Single Synchronous Step-Down Controller for Low Voltage Power Rails - [Link]

New 7″ eDIPTFT70 display – when the size matters

New 7″ eDIPTFT70 display – when the size matters:

New intelligent display eDIPTFT70 from Electronic Assembly provides all what its smaller relatives and something in addition – the size.
With the 7” size and an 800 x 480 pixels resolution, it can display a relatively considerable amount of information. Similarly like other member of family eDIP (eDIPTFT32 a eDIPTFT43), even eDIPTFT70 eliminates the need of demanding and time-consuming programming at pixels level.
All the control of the display is done on commands level, thus to display text, graphics and many other symbols is exceptionally easy and simple. Control by commands substantially accelerates development and shortens the time to market. At an application development it is possible to use predefined functions, symbols and geometric functions, bargraphs, frames, buttons and many other. In general eDIPTFT70 offers almost the same functions like other eDIPTFT family members, including almost immediate start within a few 1/10 of second.
Single +5V supply, analogue touch panel with a variable raster and software-dimmable backlight brightness contribute to the versatility of usage. In many of applications also 80 various short jingles for audio feedback can be useful. Even eDIPTFT70 contains 3 communication interfaces – RS232, I2C and SPI, that´s why it can be connected to virtually any device. Further information will provide you the eDIPTFT70 datasheet.

New 7″ eDIPTFT70 display – when the size matters - [Link]

Pages

Oct 1, 2012

Random posts