EEWeb Pulse - Volume 12

EEWeb

PULSE

EEWeb.com

Issue 12

September 20, 2011

Dino Segovis

Electronics Hacker / Rapid Prototyper

Electrical Engineering Community

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TA B L E O F C O N T E N T S TABLE OF CONTENTS

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Dino Segovis Self-Taught Hardware and Electronics Hacker/Rapid Prototyper Interview with Dino Segovis - Founder of Hack A Week.

8

Inventing an Interactive Cat Toy

BY DINO SEGOVIS Learn about one of Segovis’s newest inventions—the interactive cat toy, Whack-A-Mouse!

From Touch to Call: Tracing the Path of a Touch Gesture

11

BY TREVOR DAVIS AND STEVE KOLOKOWSKY WITH CYPRESS

Take an in-depth look into touch screens, from the physics of capacitive sensing to the final action on the screen.

Smart Energy in the Home: How MCUs Provide an Intelligent Solution

16

BY STEVE DARROUGH WITH IXYS-ZILOG Darrough discusses Smart Energy improvements for both commercial buildings and private residences.

RTZ - Return to Zero Comic

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19

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INTERVIEW

Hack A Week How did you get into electronics/engineering and when did you start?

It happened in 1973—I was 13 years old. I used to watch a TV show on PBS called ZOOM. It was produced

by WGBH in Boston. Each week they had a DIY project they called a “Zoom-do,” and one week it was a crystal radio. I ordered the “Zoomdo card” and set out to build one. I

got everything together and it didn’t work. I checked and rechecked everything, but it just wouldn’t work.

I later realized why. The instructions said to use a “Cat’s whisker” which I later found out was a thin piece of wire. I used a REAL cat’s whisker clipped from my Cat! Anyway, that project sparked something inside me. I was hooked! I started going house to house asking people if

Dino Segovis - Self Taught Hardware and Electronics Hacker / Rapid Prototyper

they had any broken or unwanted radios and or TVs I could have so I could learn about electronics. I got tons of free stuff to mess with.

My Mom and Dad were pretty cool about letting me experiment with it all. I was taking apart TV sets and old radios in my room and actually fixing a few of them. I was in love with electronics. I had an intuition for understanding it.

What are your favorite hardware tools that you use?

My Weller variable temperature soldering iron, a good set of small precision side cutters, my volt/ohm meter and my hot glue gun. I want to add a vertical mill and lathe to that list.

What are your favorite software tools that you use?

I use Adobe Illustrator to draw all my plans and schematics. It just works. It’s simple and I like to keep things simple. I also use Photoshop a lot for editing photos that I use on my projects, blogs, and for adding text and guidelines to photos. True Real Time Analyzer (RTA) is a very useful and free waveform generator and spectrum analyzer. I run it on my bench laptop.

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FEATURED INTERVIEW

Dino Segovis

INTERVIEW

The 555 timer.

What is the hardest/trickiest bug you have ever fixed?

I recently built a Fuel Injector Tester that uses two 555 timers. I had it all working fine on the bread board. I drew up a PCB layout by hand and etched a board. I placed all the components in their places, turned it on, and it didn’t work. So I sat down with the schematic and went over every single trace. They all checked out, or so it seemed. I called it a night and came back to it the next day. I went over everything again and again, testing the outputs from each part of the circuit with an LED. Suddenly the problem presented itself. One of my traces was missing a jumper! I just left it out for some reason. The LED helped a lot with that one. A very handy and simple troubleshooting tool.

What is on your bookshelf?

Digital Apollo by David A. Mindell, Failure Is Not An Option by Gene Kranz (one of my heroes). The Tube Amplifier Book” by Aspen Pittman, “Zero – The Biography of a dangerous idea by Charles Seife, and Tektronix 453 Oscilloscope Instruction Manual.

Who are your three favorite inventors?

Nicola Tesla because he believed in himself and never gave up pursuing his dreams. Alexander Graham Bell

...Hack a Week, the “Whack A Mouse!”

I just love this thing!

It was designed to be a cat toy and I brainstormed it all up without anything already out there influencing the design.

Do you have any tricks up your sleeve?

Keep it simple! This also applies to troubleshooting. The solution is usually the simple one so look there first. My approach to design is with simplicity in mind. Simple means less variables, less things that can fail. Of course this is all dictated by what the thing is being designed to do. Sometimes things have to be complex. Let form follow function and the thing will practically design itself!

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What has been your favorite project?

That would be one I recently did on Hack a Week, the “Whack A Mouse!”

I just love this thing! It was designed to be a cat toy and I brainstormed it all up without anything already out there influencing the design. It’s a silly toy that looks like a little house with two mouse holes in the front, one of which has a catnip-stuffed mouse poking out of it. When the cat paws at the mouse, a motor inside retracts it and sends another mouse out the other hole! What I love about the design is its simplicity.

It functions on nothing more than five switches, a servo, and a battery pack with an on/off switch! Lots of fun!

Do you have any note-worthy engineering experiences?

I helped inspire a group of engineers at the University Of Oklahoma this spring to build a ball launcher after a design I came up with. They needed a little more information on the mechanics of the device so I made a video describing it in detail.

They ended up building their own version. I really enjoy helping out students.

In 2009 I was in Maker Faire San Francisco with a robot I built from a hacked toy and I won an Editor’s Choice award! Kip Kay ended up shooting an interview with me which ended up in his “Weekend Projects” series. A few years ago I pioneered a technique to apply silicone to

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FEATURED INTERVIEW

What is your favorite electronic component?

for revolutionizing the way people communicate over distance, and Guglielmo Marconi for creating a device which enabled news to travel faster than ever before, thus enabling the beginning of the information age.

INTERVIEW

FEATURED INTERVIEW

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the back of the projection surface of multi-touch tables. It became known as “Tinkerman’s Method” and is a standard technique used

by DIY multi-touch enthusiasts.

What are you currently working on?

Hack a Week! I’ve been building one project per week for the past 13 weeks in a row and I intend to keep going until I complete 52, one year’s worth! It’s quite a challenge but that’s something I love. I’m good under pressure. I post a description and video of each project on www. hackaweek.com every week. My goal is to land a job as a rapid prototyper out of all this. I beta tested a Laser Range Finder for Joe

Grand on a recent post and turned it into a backup warning device for a car. It worked great and the beta test data provided useful data to Joe. Where do you see yourself in the next few years?

Working as a rapid prototyper making the big bucks and loving my job! I think the wave of Makers making things and starting businesses of their own is what will save the U.S. economy.

What challenges do you foresee in our industry?

do. We should be doing quite the opposite. Teachers spend money out of their own pockets to teach their classes! That’s just wrong! MIT electronics engineering students don’t even learn how to solder! It’s not all programming and theory. It needs to be hands-on. That needs to be brought back into schools at all levels.

How do you want to be remembered?

“He was quite simply, a Maker of Things.” ■

Getting politicians to realize that cutting funding to schools and education is the wrong thing to

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All rights reserved.

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PROJECT

By Dino Segovis

M

y website, Hack a Week, is of course my ongoing project spanning an entire year.

Coming up with a project each week is a challenge I enjoy, and one of my recent projects has become a focus to pursue further.

It’s an interactive cat toy with two mice that poke their heads out of two different holes in a tiny wooden house. Only one mouse comes out at a time and when the cat strikes at it, a switch is triggered and the mouse disappears inside while the other mouse pops out of the other hole. It’s a lot of fun to watch my cat Jayfet play with it.

The project started out as a suggestion from a friend to build an interactive cat toy. After all, I had already built an automatic ball launcher for my dogs to play with so why not something for the cat?

My initial ideas revolved around something that would get the cat’s attention and somehow react to the cat touching it. It had to be simple, as are all my designs.

I usually start with the simplest approach and work from there. I thought about sensors, possibly a

Dino Segovis - Working on the Interactive Cat Toy

microcontroller running a servo, and maybe some lights for fun. I let the ideas stew in my mind for a week or so. I get a lot of ideas as I fall asleep, so I “slept” on this one too.

One day it all came to me when I watched my other cat, Seamus, playing with a catnip-stuffed mouse. He seemed to like playing with it best when it was hidden in a pile of books or behind some

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stuff on the shop floor. The act of reaching into something to retrieve it seemed to get him very excited. It was then that it dawned on me to put the mouse inside a box and have it poke out of a hole.

The mouse would be attached to an armature and at the other end would be another mouse. By rotating the armature, only one mouse at a time would poke out.

The idea was there, and the next thing would be coming up with a

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FEATURED PROJECT

I

nventing an nteractive Cat Toy

PROJECT As I mentioned earlier, I thought about using a microcontroller to get the job done, but something told me I could get away with nothing more than a few switches.

The first thing I had to do was design the mechanical parts. So I got out some drafting paper, a few drafting tools and a technical pencil and set to work. I love to use drafting tools to get the right feel for the project. I have some computer-based 3D design tools but there’s nothing like the spontaneity of pencil on paper. In a short time I had a basic design laid out and it was time to do a cardboard mockup. This is a great way to prototype because you can move the parts and see how things interact with each other. In this case, as I moved the armature I could see how a series of switches would work. I actually laid the switches on the model and redesigned the armature to work better with them. I used some salvaged leaf switches as the main triggers on the mice, while two micro switches would serve as limit switches and a DPDT switch would handle changing the polarity of the voltage going to the servo.

I took a standard ball bearing servo and modified it for free rotation and direct drive. No pulse width modulation, just a straight connection to the motor. Next, I built a little house, fabricated the armature, mounted it to the servo and set about putting it all together.

After a few hours of trial and error,

I had a battery operated working device! It was great watching the mouse disappear inside when it was pushed down only to be replaced by another mouse poking its head out of the other hole. Now the question was, what would the cat do with it? I sat it on the workbench and got Seamus involved by teasing him with another mouse. He saw the mouse that was poking out of the hole and smacked at it. The mouse quickly went inside and Seamus quickly jumped up and ran off! He was kind of startled by the servo motor I guess. I thought I’d see what my dog, Sophie, thought of it. Turns out she loved it and played with it with great excitement. Sometimes projects take turns you never expected.

a very attractive toy to cat owners, and who knows—maybe I’ll come up with a version for dogs too.

You can see the blog entry and a video on my website here: http:// hackaweek.com/hacks/?p=153 I have always enjoyed inventing new things. I have a brain that is always considering creative ways to get things done. I use my experience with mechanical and electrical engineering, combined with experiments and life experience to solve problems.

No degrees here, just a desire to learn and a fearless attitude to try anything. If I can make a product that enriches people’s lives and maybe even inspires them to make things, well that’s a double bonus because then they join me in the creative process. ■

A few weeks later, I rescued a kitten from work and brought him home. I named him Jayfet, after a JFET transistor. Since he’s still a kitten of 12 weeks he is very curious. He liked the toy right from the start and he even figured out a way to trigger it I hadn’t thought of. He reaches inside the hole the mouse went into and pulls, which releases the limit switch. And because the DPDT switch has been flipped in the other direction, the motor turns in such a way as to make the mouse he’s pulling on come back out! Smart cat— he discovered the ghost in the machine.

My partner and I have a patent pending and plan on taking the product to market with funding from Kickstarter. I think this will be

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FEATURED PROJECT

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From Touch to Call: Tracing the Path of a Touch Gesture

Trevor Davis

Director of Marketing & Applications

This article will explore everything involved in tracking a touch, from the physics of capacitive sensing to the final action on the screen. We describe how the finger is detected and methods of determining finger position.

We follow the finger further into the phone’s software stack and see how it reaches the proper application.

Gestures such as pinch and zoom are demystified.

How is touch detected?

Almost all smartphone touchscreens react to the

Steve Kolokowsky

Sr Member of the Technical Staff

capacitance of your finger. The touchscreen contains an array of sensors that detect the change in capacitance caused by your finger. When your finger touches the screen you affect the self-capacitance of each of these sensors, and the mutual capacitance between them.

Most smart phones sense mutual capacitance sensing rather than self capacitance. Since mutual capacitance is the interaction between any given sensor pair, it can be used to collect information about every position on the screen (X * Y points). Self capacitance is only

X0 X1 X2 X3 X4 X5 X6 X7

Y0

CM

CM

Y1 Y2 Y3 Y4 Y5 Y6 Y7 Y8 Y9 Y10 Y11

CM

CM

CM

Figure 1: Mutual Capacitance Fundamentals

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TECHNICAL ARTICLE TECHNICAL ARTICLE

Baseline capacitance prior to touch Decreased capacitance during touch Return to baseline after touch removal 1pF 0.9pF

Tx

Rx

Y Drive Signal

Driver

Tx

X Receive Signal

Figure 2: Mutual Capacitance Sensing Response

capable of detecting the reaction of each sensor not each point (X + Y samples).

The capacitive sensor contains several layers: a top layer of glass or plastic, followed by an optically clear adhesive (OCA) layer, then the touch sensor, then the LCD. The touch sensor is a grid of sensors that are typically about 5mm x 5mm. These sensors are built using indium-tin-oxide (ITO). ITO has some interesting properties that makes it a great material for touchscreen construction. It’s over 90 percent transparent, but it’s also conductive. Some designs use a diamond pattern, which is visually pleasing, since it doesn’t align with the LCD pattern. Others use a simpler “bars and stripes” pattern. If you examine your device at the correct angle with good lighting, you may be able to see the ITO sensor lines with the LCD turned off.

Sensing mutual capacitance is fundamentally different from sensing self capacitance. To sense self capacitance, we typically measure the time constant of an RC circuit containing the sensor. Sensing mutual capacitance involves measuring the interaction between an X and a Y sensor. A signal is driven on each X line and each Y line is sensed to detect the level of coupling between the sensors. Interestingly, a finger touch will decrease the mutual-capacitance coupling while a finger touch increases the self-capacitance value. In either method, simply measuring the capacitance is not enough. The system must react to

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changes in capacitance, not raw capacitance. To do this, the system maintains a baseline value for each sensor.

This baseline value is a long term average of the signal that allows for signal variations caused by temperature change and other factors. One of the challenges in building a touchscreen system is establishing the proper baseline. For example, the system must be able to properly start up with a finger on the screen. The system must also be able to start with water or a palm on the screen.

Once the baseline value is subtracted from the sensed capacitance, we have an array of signal values representing the touch like the figure below: Weighted Finger Position 1 5

5 15

10 25

5 10

1 5

5 15

10 25

5 10

2

12

15

5

2

12

15

5

0

2

5

1

0

2

5

1

Figure 3: Determining Finger Location Based on Raw

Capacitance Data

Various methods are used to determine the finger position from this information. One of the simplest is a centroid (center of mass) calculation, which is a weighted average of the sensor values in one or two dimensions. Using a 1-D centroid, the X coordinate

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TECHNICAL ARTICLE sleep. When the communication transaction completes, the host driver has the data it needs to proceed.

The host driver translates the proprietary data format used by the device manufacturer into a standard format.

In Linux, the driver populates an event’s fields with a series of subroutine calls, then it sends the event with a final call. For example, creating a single-touch Linux input event looks like this:

Edges complicate the finger location problem.

Consider the array shown above if the panel ended at each of the columns. The simple centroid shown above will start to “pull” to the right as the terms on the left drop off. To counter this issue, we must use special edge processing techniques that examine the shape of the remaining signal and estimate the portion of the finger that’s off of the screen.

input_report_abs(ts->input, ABS_X, t->st_x1); // Set X location input_report_abs(ts->input, ABS_Y, t->st_y1); // Set Y location input_report_abs(ts->input, ABS_PRESSURE, t->st_ z1); // Set Pressure

Communication to the Host Processor Once a valid touch signal is present and the X/Y coordinates of the touch are known, it’s time to get the data to the host CPU for processing. Embedded touchscreen devices communicate using the venerable I2C interface or SPI. Larger touchscreens typically use USB interfaces, since Windows, MacOS and Linux all have built-in support for HID (Human Interface Devices) over USB.

input_report_key(ts->input, BTN_TOUCH, CY_TCH); // Finger is pressed input_report_abs(ts->input, t->tool_width); // Set width

input_sync(ts->input); // Send event This touch event then goes into the OS. Android saves the event’s history in the gesture processing buffer and passes the event up to the View class. Several touchscreen devices (like the Cypress TrueTouch™ products) support hardware gesture processing.

Hardware gesture processing relieves the host OS of the burden of gesture processing and in many cases it eliminates the processing of all touch data until a gesture is seen. For example, if you’re in your photo viewer, the host doesn’t have to process dozens or hundreds of touch packets to see that you want to flick to the next photo. No interrupts take place until you actually flick over to the next photo. Android’s View class determines

Although several different interfaces are employed, the OS drivers end up doing similar work with each one. We’ll discuss the Android driver in our example.

Since Android and MeeGo are both built on Linux, all three use similar drivers.

The touchscreen driver’s interrupt triggers an interrupt service routine (ISR) that schedules a worker thread.

No work is done in the ISR to maintain interrupt latency and prevent priority inversions. When the worker thread is called by the OS, it starts a communication transaction to read the data from the device and goes to

∆X

X

∆-Y

Single Touch Pan North

ABS_TOOL_WIDTH,

X

Single Touch Pan East

Zoom In

Single Touch Rotate

-∆-Y

Double Touch Pan North

Figure 4: Example of Simple Gesture Processes

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TECHNICAL ARTICLE

above is (5*1+15*2+25*3+10*4) / (5+15+25+10) = 150/55 = 2.73. We then scale this position to match the LCD resolution. If the ITO sensor pattern extends beyond the LCD’s sides, some translation is performed for this as well.

TECHNICAL ARTICLE

Once the event is seen by the application, the application reacts to the touch. This is generally done by widgets rather than the application itself. Android’s widgets include simple items like buttons, and complex interfaces like a date picker and progress bar with a cancel button. Alternatively, the application can directly consume touches. A drawing application uses a mixture of both types, using direct touch input in the drawing area and widgets for menus and buttons.

One difference between Windows Touch processing and Android is gesture interpretation. Android provides a rich library of gesture creation tools, but doesn’t provide any built-in gestures. Each designer is free to create his or her own gestures, including complex gestures like handwriting. This approach has enabled applications like character-recognition contact search, but it means that the same action may not do the same thing on two Android platforms. Windows provides a fixed set of well-understood gestures with OS-level support: GID_PAN, GID_ZOOM, GID_ROTATE, GID_PRESSANDTAP and GID_TWOFINGERTAP. These actions always cause the same actions in every application, which enables users to quickly use new applications. Each method has some strengths.

exciting applications on them. How will your next application use these new touch capabilities?

Firmware content released under GPL Android logo is reproduced from work created and shared by Google and used according to terms described in the Creative Commons 3.0 Attribution License.

About the Authors Trevor Davis is currently the Director of Marketing & Applications for Cypress’s Consumer and Computation Division (CCD) focused on User Interface in consumer products. Trevor received his undergraduate degree from the United States Air Force Academy and also holds his Masters in Business Administration. Trevor has worked in high technology positions for the military, nonprofit, and commercial sectors for the past 15 years and is fascinated by the speed of innovation in User Interface products.

Steve Kolokowsky is currently working on touchscreen solutions for Cypress Semiconductor. He has over 20 years of experience creating embedded solutions and software. Steve has been involved with Cypress’ TrueTouch solutions and USB solutions including Cypress’ best-selling USB mass storage chip, the AT2LP. Prior to Cypress, Steve worked for Cirrus Logic creating DSP tools and development kits.

Steve has written over 40 technical articles that have been published in at least six languages. He has over 10 patents issued and several more applications pending.

■

The path from touch to gesture is technically challenging and involves the interaction of many pieces. Everything from material selection to manufacturing to electronics plays a role in touch sensing. Once the touch has been digitized, it still must be located, communicated to the host, and interpreted. Now that these challenges have been met, it’s up to software developers to build

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TECHNICAL ARTICLE

which application is active where the touch occurs.

Each application that shows up on the screen has at least one View class. This class contains methods that process user input, including OnTouchListener, which passes the information received from the input driver along with additional information in a MotionEvent. If you’re used to writing windows programs that accept mouse events, you may be surprised at the difference between the variety of mouse events and the touch interface. The MotionEvent includes the methods you would normally expect from something like WM_ LBUTTONDOWN, such as GetX and GetY, but also the preceding touch positions and the amount of time the finger has been on the panel.

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The ISL89367 is a high-speed, 6A, 2 channel MOSFET driver optimized for synchronous rectifier applications. Internal timers can be programmed with resistors to delay the rising and/or falling edges of the outputs. Logically ANDed dual inputs are also provided. One input is for the PWM signal and the second can be used as an enable. A third control input is used to optionally invert the logical polarity of the driver outputs.

• 2 outputs with 6A peak drive currents (sink and source) with output voltage range of 4.5V to 16V.

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At high switching frequencies, these MOSFET drivers use very little bias current. Separate, non-overlapping drive circuits are used to drive each CMOS output FET to prevent shoot-thru currents in the output stage.

• Typical ON-resistance ~1Ω.

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Applications • Synchronous Rectifier (SR) Driver • Switch mode power supplies • Motor Drives, Class D amplifiers, UPS, Inverters • Pulse Transformer Driver • Clock/Line Driver

An under voltage lockout (UV) insures that the driver outputs remain off (low) during turn-on until VDD is sufficiently high for correct logic control. This prevents unexpected behavior when VDD bias is being applied or removed.

3.3V ENABLE

VREF+

FDELA

INVA

RDELA /OUTA OUTB

PWM

GND INVB VREF-

RDELB FDELB

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RISING OR FALLING EDGE DELAY (ns)

350 300 +125°C (WORST CASE)

250 200 150

+25°C (TYPICAL) 100 50 0

-40°C (WORST CASE) 0

5

10

15

20

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FIGURE 1. TYPICAL APPLICATION

January 31, 2011 FN7727.0

FIGURE 2. PROGRAMMABLE TIME DELAYS

Intersil (and design) is a registered trademark of Intersil Americas Inc. Copyright Intersil Americas Inc. 2011 All Rights Reserved. All other trademarks mentioned are the property of their respective owners.

Smart Energy in the Home: How MCUs provide an Intelligent Solution Steve Darrough VP of Marketing

W

e read countless articles about the Smart Grid, Smart Meters, and the vast industry with an awareness toward building the next generation of infrastructure. From generation to transmission and delivery, right up to that new meter installed outside any business or home, many Smart Energy improvements are benefiting electrical providers – especially at times when overburdened power grids have historically forced them to pay premium rates.

However, there is another story that might be even more interesting to the millions of consumers of electrical services, and that’s the story behind the final endpoint, where the energy is being delivered. There has been some

creative thinking dedicated toward making new types of devices, such as smart thermostats that communicate with the new smart meter, and with which an energy utility can control power within commercial and public buildings, or even the millions of residences across the globe. Such ability would allow complete delivery and control of the power that the consumer is paying for to be controlled even after it has been delivered. For instance, on a day in which the grid is highly impacted, our friendly neighborhood power company can decide to remotely adjust your heating and air conditioning units to help soften the load and control demand, whether it’s desired by the public or not. From that perspective, it’s absolutely certain that such a scenario works for the

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infrastructure system. And yet, what if the weather is very cold and the consumers forget that they signed that little waiver in their agreement with the utility company pertaining to the smart thermostat giving up the right to have control of over the temperature in their own buildings – even though the same consumer may have originally believed that it’s for the betterment of the whole? This type of scenario is what one might term the outside-in approach, or even the utility-controlled approach. Once started, where does it all end?

Indeed, consider water heaters, air conditioning, lighting, or even these emerging smart appliances.

In some ways, it can feel like a sci-fi movie in which a powerful Big Brother is continually watching and controlling! Of course, we

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There is an additional model which is an interesting approach, and that’s the inside-out model, in which technology is implemented inside the building to help achieve both goals. In effect, the inside-out model would measure all energy use inside the exterior wall with the smart meter, but allow all final usage decisions to be made by the folks inside that wall who pay for what they use, yet still retain control of the decision as to how much to use and when. Now both of these methods are still being accomplished to some extent with similar technology, but apply the process somewhat differently.

These applications are supported by smart little microcontrollers that have clever embedded capabilities to monitor, alert, notify and advise both the end customer and utility services when power usage is at peak load, or when usage is detected during more expensive periods during the day.

Let’s say you’ve got a new clothes dryer, and it’s smart enough to use the MCU real-time clock and communicate wirelessly with the external meter. This dryer, being so smart, advises when doing a load of clothes is both grid-smart and cost-wise. During the middle of the day, rates can be at their highest, and the dryer flashes a warning notification to that effect.

After 9:00 p.m., however, this smart dryer advises that it can dry the same load of clothes for $.50 less, clearly displayed on its instrument panel. In effect, the dryer becomes

a helpful power adviser. Multiply that by how many loads of clothes a busy family dries each month and it quickly adds up to a significant savings off the family power bill.

Look at a new smart water heater with a microcontroller that works on a cycling function. Basically these water heaters are large batteries that hold heat for 1-2 hours and don’t need the full heat blasting always on, or even leveraging an instant on feature or something pretty close to what is an acceptable time to wait for a hot shower, let’s say five minutes. Now by implementing a microcontroller with a RTC feature, that same water heater can be cycled through timing sessions

At the end of the day, the phrase “Smart Grids start with Smart Folks” increasingly applies to those who are not only creating, but intelligently using the brighter ideas and solutions we build every day. to keep the water hot and ready but reduce the energy used by 30-40 percent. And, how about all those vampire electrical devices that relentlessly drain little bits of power all day, all week, all year, hour on the hour? There may be several

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perspectives as to just how much energy is wasted with these types of devices, but when that power bill hits at the end of the month, people look at it and wonder, “Where did all that power go?”

This is, of course, only a sample of where leveraging clever little devices using microcontrollers can save us huge amounts of otherwise wasted power which, if saved, can yield savings benefits all across the new smart grid. And, if we’re listening, we’re noting that the world is in a big buzz about usage awareness and self-correcting power usage behavior. Today’s microcontrollers are like an army of mighty energy warriors that protect us from wasted energy in many ways, including their ability to sense usage in a multi-level manner, whether the application is motion sensing, power sensing, metering and monitoring; they’re always on watch and ever-effective at helping achieve good power utilization. Microcontrollers indeed offer a wide range of capabilities to manage not just one function but several important tasks all at once, making them suitable as very agile solutions. Many now are being tailored for specific energy-saving tasks that optimize millions of devices in use everywhere today, such as motors, pumps, and fans that run for long periods of time (whether they’re really needed or not). Picture an example of how microcontroller-driven smart solutions can temper the energy usage of digital signage that would otherwise continually run when no one is present. Or, imagine how a smart MCU solution can inject energy savings into the escalator at

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shouldn’t heap on too much gloom and doom – but it certainly won’t hurt to keep a sweater handy.

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So how do all of these clever new systems get enabled? Well it’s your home-town developers and engineering heroes who are paving the way. These creative and talented folks spend hours coming up with new visions and ideas for utilizing microcontrollers to add the next level of optimization to the new and existing items we all use throughout our lives. Whether they

exist in the factory, our schools, or in our homes, most everything we touch or gain a benefit from came from the mind of a dedicated engineer that is always raising the bar to the next level. At the end of the day, the phrase “Smart Grids start with Smart Folks” increasingly applies to those who are not only creating, but intelligently using the brighter ideas and solutions we build every day.

About the Author Steve Darrough is Vice President of Marketing at IXYS- Zilog.

Steve joined Zilog in 2008. Steve possesses more than twenty

years of technical engineering and marketing management experience, leading branding and marketing programs. Prior to coming onboard with Zilog, Steve held marketing management and technical engineering roles at Intel Corporations for over 14 years where he had several teams driving new technologies directly relating to the current products initiatives. His teams drove worldwide programs in evangelizing new technologies and accelerate adoption. Steve has a Marketing Degree from the University of Oklahoma. ■

Figure 1: ZMOTION Module, an example for enabling fast motion sensing to save energy

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the Mall. The new age of energy on demand is simply accelerating with more of these intelligent methods being applied, even where it affects the preventive – and therefore proactive – maintenance of these same intelligent systems.

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