As noted in an earlier edition of this newsletter, Embedded.com columnist Jack Ganssle has put out the word on a “555 contest ” he’s excited about. The contest is for imaginative designs based on the venerable 40-year-old but still very useful 555 timer. It is sponsored by Chris Gammell of The Amp Hour and Jeri Ellsworth.
They’re asking you to create a new design using one 555, or hundreds. For more information about the contest and where to submit your design idea click here.They’ve even lined up some prizes for the winners.
Because the deadline for the contest entries is so close – March 1, with acceptance of submissions to begin on Feb. 21 – I thought you deserve a little inspiration and some examples of other designs using the 555 timer. Included here are links to some recent 555-based design articles on Embedded.com as well as a collection of 555 tips and tricks from our sister publication, EDN Magazine. For even more inspiration, I searched YouTube for online 555-related videos: classes, tutorials and hands-on demonstrations that you can access by clicking here.
I am amazed at both the number and diversity of 555-timer apps. This is a much different picture than when I became aware of one of the first 555 ICs in an electronics class I was auditing at the California Institute of Technology, shortly after graduation from Columbia University. About the same time, Intel had just released its 4004 four-bit microprocessor, the world’s first single-chip MPU and we were among the first to have a chance to play with it.
The 4004 is now history, succeeded by Intel’s later 8-, 16-, 32- and 64-bit successors, but the 555 timer is still going strong, with applications numbering in the thousands and almost as many articles.
I am ready to be impressed yet again as you develop your designs for this contest (which has five categories of designs: Art, Complex/Extreme , Minimalistic , Utility and Best In Show ). Although Chris and Jeri will publish the winners on their 555 contest site, I would like to hear from you about your designs as well – runner-ups as well as winners. Have fun!!! And good luck. (Embedded.com Editor Bernard Cole, email@example.com, 928-525-9087 )
555 Timer Tips & Tricks
Reliable 555 timer doesn’t falsely trigger
Create LED-lighting patterns without a controller
555 timer eliminates LED driver need for MPU control
555 timer drives multiple LEDs from one NiMH cell
Analog switch converts 555 time into PWM
Make a simple ramp generator for stepper motors
Use a 555 timer as a switch-mode power supply
555 makes handy voltage-to-time converter
Automatic control starts loads softly
Simple circuit generates clean sine waves
Analog circuit enforces servo response, sets other parameters
When you need a reliable analog-only circuit to manage a servosystem, this circuit offers control of critical parameters with low-value Rs and Cs.
Building a reliable capacitive-sensor interface
Capacitive sensors on printed-circuit boards are usually in the range of 50 fF to 20 pF, making it difficult to detect small changes accurately. Thus, while these increasingly popular sensors offer unique advantages, they require a suitable analog interface.
Designing high-temp electronics for auto and other apps
High-temperature semiconductor technologies can survive temperatures approaching 400°C, but careful design of the product is required to deliver cost-effective devices achieving stable, predictable performance.
Move over RC: silicon timing has you beat
Using an RC-circuit comes with a number of significant limitations. This, however, is about to change with the emergence of a new class of timing devices, based on silicon oscillator technology.
Replacing chemical battery storage with supercapacitors
The use of super-capacitors for energy storage has advantages, as well as disadvantages, compared to chemical, battery storage. The challenges associated with charging and retrieving energy from a super-capacitor system have to be factored into the cost/benefit analysis.
Save power & real estate with a programmable reset controller
The long time delay of the Hard Reset poses a design problem because delays into the tens of seconds call for very large value resistors and capacitors. A programmable reset timer becomes the obvious solution when considering long delay times or multiple timers. .
Slow Response Servo Circuit
The circuit described in this article provides a very smooth adjustable servo response without having to use a high value electrolytic capacitor or very large value resistors.
High performance frequency reference design using a PWM
In the design of a circuit for PWM control, a 555 timer can be used on its own as a modulator. Unfortunately it is not possible to vary the modulation from zero to 100%, which limits its usefulness. However, the 555 timer can be used as a sawtooth oscillator to set the modulation frequency.
Nordic releases chip for Bluetooth low energy
Nordic Semiconductor ASA has released the µBlue nRF8001, which it reports is the first fully qualified Bluetooth v4.0 low energy design to combine the radio, link layer, and host into one end product listing (EPL), which enables designers to create new Bluetooth end products without any additional listing fees.
Cantata++ 6.0 offers cost-effective intelligent unit/ integration test
IT services company IPL has launched Cantata++ 6.0, the latest unit and integration testing software for C and C++ embedded systems developers.
DesignCon: National, Rambus rev to 20G+
National, Molex and Rambus will be among dozens of companies at DesignCon unveiling capabilities to drive signals to 20 Gbits/s or higher for next-generation systems.
DesignCon panel mulls over delayed design skeds
At DesignCon here a panel of four designers from Broadcom, Nvidia, Netlogic, and Juniper Networks, agreed that designs need to meet different “good enough” specs for different markets.
Agilent takes signal/power integrity test at DesignCon
Agilent is demoing its Advanced Design System 2011 as a power integrity solution at DesignCon here, which aims to solve power integrity problems that are complicated by heavily perforated power and ground planes.