Flylogic is known for their skills in reverse engineering chips. They were familiar with Atmel smartcards AT90SC3232 and AT90SC3232C and assumed that the AT90SC3232CS was similar but with an extra IO pad. They discovered the AT90SC3232CS is a completely new design based on the larger AT90SC6464C device,
Get all the fascinating details on the exploration of this smartcard and images at Flylogic’s Analytical Blog.
Atmel AT90SC3232CS smartcard destruction - [Link]
I’ve blogged previously about the development process for my latest project, an artificial die designed for die-based Role Playing Games. When I started this project, I had several design goals in mind: I wanted it to be extremely small and easy to carry, yet have 6 buttons to “roll” each of the standard sizes of die (D4, D6, D8, D10, D12, and D20). I also wanted it to based on a Random Number Generator (RNG) implemented in hardware instead of using the built in pseudo-random number generator. As those who have been watching the Show And Tell will know, I’m proud to say that I’ve succeeded. If you’d like to see it in action, a short demo video is available here..
A New Electronic Die - [Link]
This simple circuit that converts a 5V PWM signal into a variable precision reference voltage with a rang of -2.5V to +2.5V. Many designs, like a digitally controlled power supply, programmable dummy load, etc, require a Digital to Analog Converter to supply a stable reference votlage. [via]
The circuit described here uses the ubiquitous LM431 shunt regulator to implement a second-order Sallen-Key low pass filter together with a level shifter (see the figure). Compared to the traditional approach, it provides a far sharper roll-off along with a low-impedance output, bipolar output. It will produce a –2.5- to +2.5-V output with a 0- to 5-V PWM signal input. The value of Vout is equal to (5 V × dc) – 2.5 V, where dc is the PWM duty from 0.0 to 1.0 (0% to 100%)
Digitally adjustable precision reference driven via PWM - [Link]
Horto domi is an open hardware raised-bed garden unit with environmental control and monitoring via web-interface thanks to Arduino Ethernet. DIY sensors, such as those collecting moisture and temperature data help monitor the environment within the dome and will eventually be used to automate conditions. The goal is to grow whatever you want, whenever you want, wherever you are. Horto domi is Latin for ‘Garden at home.’ It’s a statement to healthful food independence, a “neo-renaissance” tip of the hat to Arduino, and it sounds like horticultural dome. Particular consideration was taken in this prototype’s design to maximize the mineral and nutrient value of the beyond-organic produce and minimize environmental contamination risks.
Horto domi: the Open Garden - [Link]
Viktor made a sound trigger for his DSLR camera:
Now that I can take pictures of lightning I decided that I also want to be able to trigger my camera with sound.
An op-amp filters and amplifies a microphone signal. The output is fed to a PIC microcontroller that triggers the flash when the sound reaches a certain level. The trigger sound level and shutter delay are set with a pot. [via]
Lil Bang – Sound trigger for cameras - [Link]
Component packages explained – [via]
Personally, I’ve found all the little acronyms when looking for components to be a little confusing and I’m sure that I’m not the only one that’s been through that. Whats a TSSOP? Whats the difference between SIP and DIP? It can get very frustrating, so this will explain everything for you!
Well there are many different components out there and with that, there have to be different packages to fit different needs such as space availability, prototyping, and different circuit board layouts. The entire list of the more well-known packages, others may be lurking in R&D that we don’t know about, goes something like this : CDIP , PDIP , SPDIP, SIP, SDIP, SOIC, TSOP, SSOP, TSSOP, PLCC, QSOP, VSOP, LQFP, PQFP, CQFP, TQFP, CGBA, and QFN. Its mostly all about space on the board, which kind of package utilizes the precious space on the circuit board the best. So lets start with the descriptions!
Component packages explained - [Link]
SMD Packages explained!. The Funkiester writes – [via]
Hello! Well as a result of all the great feedback from the component packages, I’m doing another post about SMD packages! I may be using some of the terminology from the last post in here as well, so just in case, here is the last post.
First off, SMD means Surface Mount Device; There is another acronym used that means pretty much the same thing which is SMT, and that means Surface Mount Technology. This’ll be describing the various packages that an LED can come in, as well as resistor and the more common capacitor packages as well as many other surface mount devices. The big rule about SMD is that many packages are represented by a 4 digit code. The first two digits indicate its length and the second two digits indicate its width. So an 0603 package would be .06″ x .03″ . Although if it isn’t represented by a 4 digit code, that doesn’t mean that it isn’t an SMD component, all that means is that you’ll have to do a little more searching to find the dimensions of your specific component.
The most common packages are the: 0603 , 0805 , 1206, 2512, and the SOT. although we will be discussing the 0606, 1204, 1210, SOD, PLCC, Chimney-Type, 3528, 5050, A, C, D, E. The space on the board where the SMD will sit is called the footprint, and the footprint is like a little diagram as to where the component is to be soldered on the board and how much space it takes up.
SMD Packages explained! - [Link]
A RC Wien Bridge oscillator outputs a pure sine wave. The frequency depends on the resistor-capacitor combination in the oscillator. Embedded Eric built one using instructions from “Analog Circuit Design“:
I have been slowly reading through Jim Williams “Analog Circuit Design” book. Not slowly because it is boring, it is actually very interesting and a good read; I just get easily distracted and it has been a few weeks since I picked it up. I am about 200 pages or so into it and my favorite chapter so far has been the one where Jim Williams describes the steps he took while recreating William Hewlett’s Model 200A Wien Bridge Oscillator. It is essentially the same project described in Linear Tech’s AN43 Appnote, but with a lot more background and Jim describes the inner workings very conversationally in the book.
Jim’s first iteration of the circuit consisted of a RC Wien Bridge, an LT1037 Opamp and a #327 Lamp. The Lamp is used as a variable resistor that starts out at a very low 98 Ohms DC resistance that helps get the Opamp oscillating (because of the increased gain) and ends up stabilizing at around 235 Ohms once it heats up (thus servo-ing the gain down to an equilibrium point that keeps the circuit oscillating).
RC Wien Bridge oscillator – pure sine wave - [Link]
Here is a rather simple but practical use for digital electronics…..dice! (or in the case a single die)
Unlike many of the kits found online this one does not use a micro controller. The entire circuit is based around 74LSxx logic ICs and a 555 timer for a clock.
7400 competition entry: Digital die (74XX Family) - [Link]
Over the years most of us have purchased a few multimeters, and perhaps some of the older ones are still hanging around like faithful friends. You might prefer one ahead of the others, perhaps because it is easier to use and you think that it is probably more accurate, but you wonder just how accurate it is…
Determining the accuracy of a DMM is not easy. Often manufacturers will totally ignore accuracy in their specifications, or if it is a high quality model, they might say something like ±0.02% ±3 digits ±4mV/°C — which does not help either.
This gadget will output a precise 2.500V with an accuracy of ±1 mV. It is great for checking any meter, it does not cost much, and it must be one of the simplest projects around.
MAX6325 Precision Voltage Reference - [Link]