EDN Magazine Issue 2012-01-19

19.4 MB·English

by  Reed Electronics Group

SPECIAL SECTION:
19 2012 GLOBAL
JAN ELECTRONICS
DISTRIBUTION SPECIAL
Issue 2/2012
Page S1
www.edn.com
EDN.comment Pg 10
Teardown Pg 24
Design Ideas Pg 77
The silence of the
VOICE OF THE ENGINEER
circuit Pg 86
ANALOG DESIGN IN THE
Noise wars:
Projected
21 CENTURY:
capacitance ST
strikes back
against CHALLENGES, TOOLS,
internal noise
Page 61 AND IC ADVANCES
Use a Page 66
switching
regulator to
power a high-
speed ADC
Page 73
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contents
1.19.12
Noise wars: Projected
capacitance strikes back
against internal noise
61Charger and display noise affects
touchscreens, but there are ways to
Analog design in the 21st
tackle this problem.
century: challenges, tools,
by John Carey,
and IC advances Cypress Semiconductor Corp
66 Analog-circuit-design engineers over- Use a switching regulator
come new challenges with advanced
to power a high-speed ADC
tools and ICs.
by Steve Taranovich, 73A properly designed switching regu-
Contributing Technical Editor lator can improve the power efficien-
cy of low-power, high-speed ADCs without
significantly sacrificing performance.
by Thomas Neu, Texas Instruments
S1Special section:
2012 global electronics distribution special
COVER IMAGE: SHUTTERSTOCK/YOSHI HOHOKABE
15V
15V
D E S I G NI D E A S
C +
3 R
10 μF 5
50k R
6
50k
77 Make an asynchronous clock for VPX-based PCIe systems
R
4
10k 3 + 8 78 URs1e a photoelectric-FET optocoupH1le1Fr 3aMs a linear voltage-controlled potentiometer
R1k7 VIN 1R03k 2 −LM4358A 1 8802 WS309i.m0i1Cr e1μpFleles sc itrecmuitp teersattsu rtew mistoendi-topra ih12r acsa bdlaetsa-log6ging capVaObilities
4
H11F3M
R2 ▶ Find out how1 to submit6 your own Design Idea: http://bit.ly/DesignIdeasGuide.
1M PHOTO FET 2
2
4
C
[w ww.edn.com] 4 JANUARY 19, 2012 | EDN 5
0.01 μF
PHOTO FET 1
EDNDI5236 Fig 2.eps DIANE
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contents
1.19.12
MOSFETs

pulse
Dilbert 14
Small Power MOSFETs
Designed for Handheld Devices
12 BLDC-fan motor driver 18 I ntel rolls out 32-nm Atom,
employs sensorless preps 22-nm Ivy Bridge
sinusoidal architecture
18 S mall MEMS modules boost
14 Foundation readies consumer-device sensitivity
$25 PC for launch
18 C AN transceiver isolates
16 SLI eliminates the need signals to 5 kV rms, handles up to 2 A up to 4 A up to 7 A up to 10 A
for touch in MEMS temperatures to 125°C
Dual SOT-23 TSOP-6 PQFN 2x2
applications
19 D ifferential op amp tackles PQFN 2x2
16 Tiny dc/dc power modules common-mode voltage as high Gate Drive - 4.5V Optimized,
target rugged industrial and as ±275V 2.5V Capable, 12V Maximum
avionics environments Max. R @
20 V oices: Mark Mitchell: An early DS(on) Part
BV Package
18 Microcontrollers target interest in computers leads to DSS 4.5 V 2.5 V Number
(mΩ) (mΩ)
smart metering lifelong ambition
PQFN 2x2 31 53 IRLHS2242
-20V
departments & Columns SOT-23 54 95 IRLML2244
PQFN 2x2 12 16 IRLHS6242
SOT-23 21 27 IRLML6244
86 20V
Dual
45 62 IRLHS6276
PQFN 2x2
PQFN 2x2 16 20 IRLHS6342
TSOP-6 18 22 IRLTS6342
30V SOT-23 29 37 IRLML6344
Dual
63 82 IRLHS6376
PQFN 2x2
83 FEATURES:
• Available in both N & P Channel for
simple design

8 EDN online: Join the conversation; Content; Engineering Community • Latest silicon technology offering low
R for increased battery life
10 EDN.comment: CES is over; it’s time to start designing DS(on)
• 2.5V drive capable available for 1-cell
22 Baker’s Best: Designing with temperature sensors, part five: Li-Ion Battery Applications

IC temperature sensors • PQFN package offers high power density
reducing system size
24 Teardown: Vizio VTAB1008 tablet: symbiosis of man and machine
26 Mechatronics in Design: Theory and practice For more information call 1.800.981.8699
or visit www.irf.com
83 Product Roundup: Optoelectronics and Displays
86 Tales from the Cube: The silence of the circuit
EDN® (ISSN# 0012-7515) is published semimonthly by UBM Electronics, 600 Community Drive, Manhasset, NY 11030-3825. Periodicals
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Volume 57, Number 2 (Printed in USA). Disney’s Coronado Springs Conference Center
06-08 Feb 2012
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JOIN THE CONVERSATION CONTENT
Comments, thoughts, and opinions shared by EDN’s community Can’t-miss content on EDN.com
In response to “Get off the sidelines,” an editorial by
Suzanne Deffree, http://bit.ly/sO0XUF, that was shared
via social media on EDN’s Facebook wall, http://on.fb.
me/EDNFacebook, SpecTECHEDU commented:
“Best line of the day: ‘Progress: It’s what engineers do.’ We think progress
is what engineers do best.”
In response to “Peering inside a portable, $200 cancer
detector,” by Jim MacArthur, Electronic Instrument
READERS’ CHOICE 2011:
Design Laboratory, Harvard University, http://bit.ly/
PEASE AND WILLIAMS, LEDs,
xELhdN, Pop Mircea, a physics researcher, commented:
MEDICAL ELECTRONICS,
“It’s quite a nice accomplishment. It’s quite a quest to tame such electronic
MORE …
devices, specific to NMR [nuclear-magnetic-resonance] instrumentation, in
Take a look back at 2011 and what
order to make them so (relatively) simple and ergonomic. I’ve seen some
the year brought for engineers with
articles about NMR digital-processing units using FPGAs. I would still vote
this collection of popular EDN content
for FPGAs (maybe along with an additional DSP core) since these devices
on electric vehicles, LEDs, ham radio,
can be completely ‘reordered’ by reprogramming. It seems to me that the
medical electronics, and more.
RF and acquisition part is much more expensive than the processing part.”
http://bit.ly/zusvZ7
In response to Margery Conner’s “What’s inside a smart
meter?” http://bit.ly/A8TSIh, Jack Haesly commented:
“I have heard these smart meters can and do spy on the
individual user in that they can and do report most aspects
ooff eenneerrggyy uussee iinn tthhee iinnssttaallllaattiioonn.. …… IIff ttrruuee,, wwhhaatt’’ss uupp wwiitthh tthhaatt?? JJuusstt hhooww CIRCUIT-
detailed is the report, and to whom does the utility company sell the PROTECTION
available data? When energy companies install these systems, they do BASICS: ISSUES AND
not, in my opinion, divulge all aspects of what the meters actually are
DESIGN SOLUTIONS
capable of transmitting or who they are targeting.”
The inconsistency of the power grid
places the reliability and efficiency
EDN invites all of its readers to constructively and creatively comment
of electronic equipment in constant
on our content. You’ll find the opportunity to do so at the bottom of each
jeopardy.
article and blog post. To review current comment threads on EDN.com,
visit http://bit.ly/EDN_Talkback. http://bit.ly/wmH2V0
ENGINEERING COMMUNITY
Opportunities to get involved and show your smarts
More than 100 tutorials and technical-paper sessions in 14 conference tracks focused on the
pervasive nature of signal integrity at all levels of electronic design—chip, package, board, and
system—make DesignCon 2012 the place where chipheads connect. Running Jan 30 through
Feb 2 at the Santa Clara Convention Center in Santa Clara, CA, DesignCon offers numerous
educational and networking opportunities. Find more information and register to attend at
http://designcon.com.
[w ww.edn.com] JANUARY 19, 2012 | EDN 9
edn.comment
BY patrick mannion, director of content
ment-business-hardware division. I’ll
be looking forward to catching up with
Spillinger after his keynote speech to get
more information on his vision of gam-
ing, underlying architectures, and the
future of sensor-based user interfaces.
Finally, on Wednesday, Prith Banerjee,
senior vice president of research at
CES is over;
Hewlett-Packard and director of HP
it’s time to start designing Labs, the epicenter of the company’s
R&D, will give us his take on where the
A opportunities lie and what HP may be
t press time, I was preparing to fly to Las Vegas for the 2012
doing about it. Banerjee’s own research
CES (Consumer Electronics Show), where I am looking for-
interests include VLSI computer-aided
ward to unearthing and presenting for evaluation some truly design, parallel computing, and com-
innovative, exciting, and useful technology and devices pilers. He is the author of about 300
from among the thousands of gizmos and gadgets that will research papers in these areas, so his
thoughts will be worth tapping into.
inevitably catch my curious eye. By the time you read this,
The technical tracks focus on signal
however, CES will be behind us; you will have already determined the good,
integrity, as usual, but there’s a clear
the bad, and the ugly; and either you will be looking forward to getting your
emphasis on 3-D packaging, high-speed
hands on the coolest gadget or, more likely for an EDN reader, you’ll have interfaces (28 Gbps, for example),
already poked holes in the designs shown at CES 2012 and are now well FPGAs, analog design and verification,
on the way toward imagining how you or your design team can do better, and PCB layout. For test, it’s not news
that high-speed serial buses are causing
possibly even before CES 2013!
concern for designers, so to help provide
With that thought in mind, I would and, of course, happy-hour opportuni- some hands-on help, Agilent has agreed
like to invite you, on behalf of UBM ties to mix with your peers and digest to step you through the challenges and
Electronics and Barry Sullivan, IEC the information while visiting a packed the testing tools available in high-speed
director and technical-program chair, exhibit floor. Even at this stage, we’re serial-design workflow, from design and
to DesignCon 2012, Jan 30 to Feb 2, in still trying to squeeze in more, so keep simulation through turn-on, debugging,
Santa Clara, CA. It may be no coinci- up to date at www.designcon.com. and system and compliance testing.
dence that this conference so quickly To set the tone for each day, we’ll Don’t miss the session “Design and Test
follows CES, the biggest display of elec- have keynote speeches from industry Challenges in Next Generation High-
tronic designers’ wizardry. DesignCon visionaries, starting on Monday, Jan 30, Speed Serial Standards.”
focuses on both inspiration and deep- with Joe Macri, corporate vice presi- Elsewhere at the conference, I’ll be
dive exploration of the technologies dent and chief technology officer of leading a panel discussion with four of
and techniques designers can apply AMD’s client division. Macri is also the brightest minds in test to see where
toward forging the next generation of chairman of the JEDEC JC42.3 DRAM the challenges are for you, the design-
electronic devices and systems. Committee and vice chair at large of er, and what test companies are doing
This year’s conference is jam-packed the JEDEC board of directors. His areas about them. Among several teardown
with something for everyone look- of expertise are in CPU, memory, and sessions, iFixit’s Kyle Wiens will be
ing to get the right signal from Point graphic design, with more than 20 pat- comparing Amazon’s Kindle Fire with
A to Point B intact—or at least in a ents pending or granted. Go to http:// Barnes & Noble’s latest Nook, and I’ll
decipherable form—as efficiently and bit.ly/z0W24o for an overview of what’s be tearing down the Vizio and gTab-
elegantly as possible, from die, through happening at DesignCon with respect let tablets and a Cisco Linksys E3200
packaging, to board and system. So it’s to high-speed memory design. router. Read more about the Vizio tablet
safe to say that “everyone” includes just Ilan Spillinger, corporate vice on page 24 of this issue and at http://bit.
about every engineer out there involved president for hardware architecture ly/zKZT42. If you’d like to participate in
in design and test. at Microsoft, will kick off the day on the discussion on tablet design and the
Toward that end, we have panels, Tuesday. His group leads the Xbox 360 state of Wi-Fi design, let me know. I’ll
technical tracks, teardowns, awards and Kinect architecture and verifica- be sure to include you. I look forward to
(DesignVision and Test & Measurement tion, silicon design, hardware incuba- seeing you there!EDN
World’s Best in Test), tutorials, focused tion, and business-development efforts
educational tracks, breakout sessions, for Microsoft’s interactive-entertain- Contact me at [email protected].
10 EDN | JAnUARY 19, 2012 [w ww.edn.com]