Embedded Developer: March 2015 by EEWeb Magazines

W E N

Industrial-Grade

MODULES

Transform the MAKER MOVEMENT

MARCH, 2105

Simplicity and Price Point in a Production-Ready SOM

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TECH REPORT Where Wheels Meet Rails Embedded Modules for Train Axle Monitoring 82

15.0

14.5

14.0

13.5

13.0

η eGaN FET η MOSFET

12.5

Pout eGaN FET Pout MOSFET

25 30 35 40 DC Load Resistance [Ω]

12.0

TECH SERIES Output [W]

Efficiency [%]

CONTENTS

Wi GaN Wireless Power Amplifier Comparison

Figure 3: Load variaAon eﬃciency of MOSFET and eGaN FET in a class E wireless power ampliﬁer

Understanding Soft Errors in Semiconductor Memory

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DESIGN CHALLENGES Rolling stock is the most maintenanceintensive part of the railway system and train axles, and wheels and brakes are the most vulnerable. The axles of a running train have to be constantly measured in “real time“ for diagnostics and safety. Other requirements include: • Measurement and storage of the temperature profile of brakes, wheels, and axle bearing to detect cracks and overheated parts

Where the

WHEELS Meet the

RAILS

• Time-synchronized measurements by up to 6 units at individual parts of the axis • Storage of data on a rugged media and encryption of all data sent to the base station • Temperature range as wide as possible • Power dissipation as low as possible to avoid self-heating • High reliability plus long-term product availability and support

Designing Embedded Equipment to Monitor Axles on a Running Train 4

TECH REPORT

DESIGN SOLUTIONS • 2x SATA SSD for storage of measured temperature data • The QorIQ embedded module (Freescale P2020 QorIQ™ P2 platform MCU) provides: » A reliable NOR-Flash to boot from » 2x GBit Ethernet for system interconnection and connection to the base station » 2x SATA interfaces and IEEE1588 support for time synchronization amongst the units for all data being stored » Security Engine for encryption of data transferred to the base station » Industrial grade temperature range: -40°C…+85°C

A TQMP2020 module with a Freescale QorIQ can save you design time and money Benefits of TQ embedded modules (shown above—ready for mounting on a starter kit): • Smallest in the industry, without compromising quality and reliability • Bring out all the processor signals to the Tyco connectors • Can reduce development time by as much as 12 months

» A fanless design with lowest possible power consumption

• The TQMP2020 module comes with a Freescale QorIQ™ Power Architecture® MCU and supports Linux and QNX operating systems

» A module size being more than 22% smaller than comparable ones from the competition

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» Product longevity support for more than 10 years

TQ-USA is a brand of modules distributed in North America by Convergence Promtions

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By Bhasy Nair, Director of Global Field Applications Engineering and Michael A. de Rooij, Executive Director of Applications Engineering, Efficient Power Conversion (EPC)

TECH SERIES

Wi GaN:

A Comparative Analysis of Class E and ZVS Class D Amplifiers for Use in Wireless Power Transfer Systems Wireless power transmission is one of the fastest growing applications in both consumer and industrial electronics. As embedded systems within both transmitting and receiving devices, it is crucial for power system designers to understand the fundamental system design and the components contributing to its performance. There are three main constituents of a wireless power system with the amplifier, a transmit coil, and a receive coil typically housed within a receiving device as shown in figure 1 [1].

At the heart of the wireless power system is the amplifier—identifying the best amplifier topology and most efficient components is the focus of this article. Distinguishing attributes of a good amplifier such as EMI, load impedance drive range, and the ability to operate in accordance with multiple standards will be addressed. Wireless Power Amplifier Topologies Selecting a standard to which to design an amplifier is the first task, since each standard requires a different power architecture and communications protocol. Over the past several years, three standards for wireless power have emerged – the Wireless Power Consortium’s Qi, the Power Matters Alliance [10] and the Alliance for Wireless Power (A4WP), also known as Rezence® [2]. The Rezence standard centers on the highly resonant loose-coupling approach that allows much larger distance and spatial freedom between transmit and receive units. The operating frequency of Rezence standard is 6.78MHz, which is part of the ISM Band. The two most popular amplifier topologies for resonant power transfer are class E and ZVS class D.

Both topologies yield high performance, but for Class E amplifiers special low capacitance high voltage MOSFETs are required to accomplish operation at this high frequency. Replacing the silicon-based power MOSFET with an enhancement-mode gallium nitride eGaN FET [3], the losses in a Class E amplifier can be reduced by 20%. This decrease in losses is due to the lower gate capacitance and on-resistance of the GaN FETs relative to MOSFETs for similar output capacitance and voltage rating. Thus, they require and dissipate less energy. In turn, this means that GaN FETs can operate at higher frequencies resulting in higher performance capability for the amplifier. The ability to switch at higher frequencies is critical for the implementation of the Rezence. Limitations of Class E Amplifier: Rapid Roll Off of Efficiency and Output Power Silicon power MOSFETs are commonly used in class E amplifiers such as the one shown in figure 2. The gate charge of MOSFETs are much higher than that of a eGaN FET and the higher drive power required for MOSFTs has a major impact on the overall efficiency of the system. As shown in Figure 2, the superior switching

V/I VDD Amplifier

Source Impedance Coil

Device Coil Impedance

Matching Network

Supply

Matching Network

LRFck

Rectifier

Le Load

Csh Source

Device

Figure 1:pWireless system components— Figure 1: Wireless ower spower ystem with with components – source, ampliﬁer, and device Figure 2: Class E amplifier. source, amplifier, and device. Figure 2: Class E ampliﬁer

ZLoad

One major setback of the class E amplifier is that the output power and efficiency rapidly roll off as the output DC load increases, and shown in Figure 3. This roll-off condition needs to be corrected by complex and expensive matching circuits that can adapt to the changing load conditions [4]. ZVS Class D Amplifier for Wireless Power Transfer ZVS class D amplifier topologies avoid the rapid roll-off and provide a higher and flatter efficiency over the entire load range. The ZVS class D amplifier is a modified class D design (shown in figure 4) that uses an “LC tank” (ZVS tank) circuit. This ZVS tank ensures that the FETs switch at or near zero voltage, even with variations in load conditions, thereby avoiding the output power and efficiency roll off seen with class E amplifiers [5]. Figures 5(a) and 5(b) show the comparison of the efficiency and load curves of both amplifiers [2].

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characteristics of eGaN FETs, with their smaller gate and drain capacitances, reveal that the losses in the eGaN FET amplifier are about 20% lower, allowing for a 5% increase in efficiency over a power MOSFET based amplifier.

Efficiency [%]

TECH SERIES

25 30 35 40 DC Load Resistance [Ω]

12.0

Figure 3: Load variation efficiency of MOSFET and eGaN FET in a class E

Figure : Load variaAon eﬃciency of MOSFET and eGaN FET in a class E wireless 3 power amplifier. wireless power ampliﬁer VDD

ZVS tank

LZVS Q1

ZLoad

CZVS

Figure 4: ZVS class D amplifier.

Figure 4: ZVS class D ampliﬁer.

3.56 x VDD

VDS

50% Ideal Waveforms

Time

Figure 5(a):4 Class E amplifier efficiency andaEnd power Figure (a) Figure Class E4 A(a) mplifier Class EE fficiency Amplifier fficiency and output as DC output load changes.

utput s load output s load changes. Figure 5Figure (a): power Class 5o(a): Epower aCamplifier lass Echanges. aamplifier efficiency efficiency and power and oputput ower o as utput DC as DC output output load changes load changes

5(b): ZVS Class D amplifier efficiency and Figure Figure 4 (b) Figure ZVS CD 4 (b) Amplifier ZVS CD E fficiency Amplifier aEnd fficiency and power output as DC output load changes. power utput power as Z load oVS utput hanges. as load Figure 5Figure (b): ZoVS 5(b): Class Dc C alass mpliﬁer Dc hanges. ampliﬁer

eﬃciency eﬃciency and power and oputput ower o as utput as DC output DC o load utput changes load changes

Environmental Impact and Compliance There are several operating conditions that can affect a wireless power system, such as; the (1) distance between the source coil and the receive coil, (2) position of the source coil relative to the receive coil, (3) placement of multiple devices on the source coil and (4) the introduction of a solid metal object to the source coil. All these factors will lead to changes in the effective coupling between the source coil and the receiving device coils. This causes the coil impedance to shift from the ideal resonance operating point, by increasing or decreasing both the real and reactive components of the load causing a de-tuning effect and adversely impacting the performance of the system. Changes in Impedance Figure 6 shows the efficiency for both the class E (red) and ZVS class D (blue) amplifiers using eGaN FETs operating through a range of reflected load reactances plotted for various reflected load resistances. Again, it is noteworthy that the ZVS class D amplifier exhibits a relatively flat efficiency over the entire impedance range compared to class E, except at resonance points, demonstrating the stable performance of ZVS class D amplifier [5].

Efficiency [%]

In order to achieve operation over the entire impedance range of a Class 3 PTU, retuning of the coil is needed which is accomplished by changing the value of the tuning capacitor. The automated process of doing this is called adaptive matching. A single retuning adaptive matching cell is comprised of a back-to-back high voltage low RDS(on) FET switch (shown in the gray boxes in Figure 8) that is connected in series with the appropriate parallel tuning capacitor to 420V retune the coil. A multi-bit adaptive switching 350V 280Vretuning circuit is. comprised of multiple of these 210V 140V cells capable of retuning the coil to within 70V the 0V amplifier capability in discrete steps. Depending -70V

4 f0 V(Coil)

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-30 -25 -20 -15 -10 -5 0 5 10 Imaginary Impedance [Ω]

Figure 5. Impact of imaginary part of impedance on efficiency

Figure 6: Efficiency impact iof reflected variations on both the classoEn (red) Figure 6: Eﬃciency mpact of load reﬂected load variaAons both and ZVS class D amplifiers (blue) driving an A4WP class 3 compliant load.

the class E (red) and ZVS class D ampliﬁers (blue) driving an A4WP class 3 compliant load

Adaptive Tuning for Optimizing Performance Figure 7 shows the range of impedance capability of both class E and ZVS class D amplifiers, on a Smith Chart® for a A4WP standard Class 3 source load. The shorter purple dashed arc arrow shows the class E amplifier range and the longer red dashed arc arrow shows the ZVS class D amplifier range. It is clear from the chart that neither of the amplifiers are capable of operating over the entire impedance range of a Class 3 Power Transfer Unit (PTU), represented by the area shaded in blue [6].

-120db -140db

10MHz

100MHz

Voltage Figure 7: Class E and ZVS class D amplifier impedance capability superimposed the class 3 standard. Figure 6. S-‐parameter chart owith f Class 3 rA4WP esonator superimposed Figure 7: Class and VS class mpliﬁer impedance with E Class E aZnd ZVS class D D ia mpedance range

capability superimposed with the A4WP class 3 standard

TECH SERIES waveform for a single-ended class E and singleended ZVS class D amplifier. Notice that the even order harmonics are absent in the current waveforms for ZVS class D whereas these harmonics are present in the class E amplifier. Even-order harmonics impact fundamental asymmetrically and are extremely difficult to filter out. Since the ZVS class D amplifier has almost zero even harmonic content in the spectrum, EMI compliance becomes less of an issue compared to a class E amplifier [8].

on the reflected load impedance change, the adaptive matching controller will activate the appropriate cell to get the coil back to resonance. Adaptive matching will also improve coil efficiency as it effectively narrows the impedance range of the coil and brings it back to operate closer to resonance. Since the operational range capability of the ZVS class D amplifier is wider than that of class E amplifier as shown in Figure 6, a smaller number of discrete matching circuits (cells) will be needed to retune the ZVS class D amplifier in order to bring it within the amplifier capability. This results in a lower cost and a more attractive system solution for wireless power transfer, particularly at higher power (> 16W).

LCoil CS2

CS3

QS1

EMI Generation Comparison Between Class E and ZVS Class D To understand the difference in EMI generation between the class E and ZVS class D amplifiers, 420V I(Lcoil) 1.2A 350V both will be simulated in LTspice [7] when 1.0A 280V 0.8A 210V operating to deliver 14W into 0.6A an A4WP 140V Class 0.4A 70V 3-compliant load. Figure 90.2Ashows the simulation 0V 0.0A -70V -0.2A -140V results of the EMI content-0.4Aof the current -210V -0.6A -0.8A -1.0A

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Figure 8: MulA-‐bit adapAve matching network

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Figure 9(a): EMI content of current waveform Class E

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Current Figure 9(b): EMI content of current waveform Class ZVS Class D.

Figure 9(b): EMI content of current waveform Class ZVS Class D

Multi-mode Wireless Power Transfer Capability The rising demand for wireless power for a range of mobile devices, such as tablets, laptops and even power tools, together with the multitude of wireless power transfer standards (i.e., Qi, PMA and Rezence) [9–11] serves to hinder adoption of this technology, as it leads to end-user confusion and loss of inter-operability. The Qi and PMA standards operate at much lower frequencies (<315kHz) compared to Rezence operating at 6.78MHz and a single multi-mode amplifier that can transfer power regardless of the standard used by the receiving device is needed. Amplifiers designed in accordance with the Qi and PMA low frequency operation cannot typically support operation at 6.78MHz operation required for the Rezence platform. Thus, in order for a MOSFET-based amplifier to support the three standards at least two sets of converters and two resonator coils will be required, making this solution cost prohibitive and bulky. The class E topology uses the FET in a resonant mode

Figure 10: Multi-mode amplifier using eGaN FETs.

at 6.78MHz and hence adopting it for a much lower frequency for Qi or PMA is not a practical solution. The ZVS class D topology amplifier can easily be modified to work as a multi-mode power converter, as shown in Figure 10. With Q3 turned off to isolate the ZVS tank circuit, the half bridge (Q1 and Q2) can be used to support Qi or PMA mode. With Q3 turned on to connect the ZVS tank circuit to the output of the amplifier, the same amplifier can now operate as a ZVS class D amplifier at 6.78MHz to drive Rezence standard products, thus providing a very attractive and competitive multi-mode solution [7]. Summary In this article, both class E and ZVS class D amplifier topologies were evaluated for their ability to address the demands of wireless power transfer to the Rezence standard. A fundamental limitation of the class E amplifier topology is that output power and efficiency roll-off rapidly with load variations the deviate from the optimal design value. The characteristics of both types of amplifiers were evaluated under the various operating conditions. Comparing the performance showed that the ZVS class D is a better choice than the class E amplifier, as it generates no even-order harmonics and can operate over a wider impedance range. In addition, a ZVS class D amplifier can be easily modified to support multi-mode operation for the three wireless power standards.

Figure 10: MulA-‐mode ampliﬁer using eGaN FETs

TECH SERIES

References [1] M. A. de Rooij, Wireless Power Handbook: A Supplement to GaN Transistors for Efficient Power Conversion. El Segundo, CA: Power Conversion Publications, March 2015 [2] Alliance for Wireless Power (A4WP), http://www.rezence.com/ [3] A. Lidow, M.A de Rooij, “Performance Evaluation of Enhancement Mode GaN Transistors in Class-D and Class-E Wireless Power Transfer Systems,” Bodo’s Power Systems, May 2014, pp 56-60. [4] Efficient Conversion Power Corporation, White Paper WP014: eGaN FETs in Wireless Power Transfer systems. www.epc-c.com [5] A. Lidow, “How to GaN: Stable and Efficient ZVS Class D Wireless Energy Transfer at 6.78 MHz,” EEWeb: Pulse Magazine, Issue 126, PP 24-31, July 2014. [6] A. Lidow, “Wi GaN: eGaN® FETs In Wide Load Range High Efficiency Power,” EEWeb: Wi Wireless & RF Magazine, Nov. 2014 pp 13-17. [7] Linear Technology, LTspice Design Simulation and Device Models, [Online] Available: www.linear.com/ltspice [8] M.A de Rooij, “Topology Performance Comparison using eGaN® FETs in 6.78 MHz Highly Resonant Wireless Power Transfer,” DesignCon 2015, Santa Clara, CA, 26-29 January 2015. [9] “System Description Wireless Power Transfer,” Vol. I: Low Power. Part 1: Interface Definition, Version 1.0.3, September 2011. [10] Power Matters Alliance. [Online] Available: www.powermatters.org [11] A4WP Wireless Power Transfer System Baseline System Specification (BSS), A4WP-S-0001 v1.2.1, May 07, 2014. eGaN® FET is a registered trademark of Efficient Power Conversion Corporation.

Understanding and Mitigating the Effect of

Soft Errors in Semiconductor Memory By Reuben George, Cypress Semiconductor

TECH REPORT

he past few decades have brought about unprecedented advancements in semiconductor

technology. However, with each advance in semiconductor technology, new obstacles to maintaining the exponential improvement of process technology arise.

Cosmic Rays dispersed by the atmosphere Source CERN

Today, CMOS technology has shrunk to such a size that extraterrestrial radiation and chip packaging cause failures at an increasing rate. Since these errors are temporary, they are called soft errors. The

A SOFT-ERROR IS A CHANGE OF STATE

first instance of soft errors was in 1978,

INDUCED BY AN

when Intel was unable to deliver its chips

ENERGETIC PARTICLE.

to AT&T due to uranium-contaminated packaging modules. Intel, while coining the

HOWEVER, UNLIKE

term “soft fail,” reported that radioactive

A HARD ERROR, THE

contamination could cause not only flips in

AFFECTED DEVICE’S

stored data, but also microcontroller lockup. At Cypress Semiconductor, we came

NORMAL OPERATION

across the first instance of soft errors in

CAN BE RESTORED

2001, when a large telecommunications

BY A SIMPLE RESET/

client found that a single soft error in an SRAM was causing hundreds of computers

REWRITE OPERATION.

in a system farm to crash.

THE FIRST INSTANCE OF SOFT ERRORS WAS IN 1978, WHEN INTEL WAS UNABLE TO DELIVER ITS CHIPS TO AT&T DUE TO URANIUMCONTAMINATED PACKAGING MODULES.

As memory process technology scales for improved performance and power, the reduced voltage and shrinking node capacitance makes these devices more susceptible to soft errors. Soft errors not only corrupt data, but can also lead to loss of function and system critical failures. Industrial controllers, military equipment, networking systems, medical devices, automotive electronics, servers, handheld devices, and consumer applications are especially vulnerable to the adverse effects of soft errors. An uncorrected soft error can lead to system failures in mission critical applications such as implantable medical devices and automotive engine control, as well as high-end security systems. Soft errors have the potential to cause elevator controllers to malfunction, while in a networking system it can cause the traffic to go haywire. Such occurrences, though rare, have the potential to cause havoc at a massive scale. A soft-error is a change of state induced by an energetic particle. However, unlike a hard error, the affected device’s normal

operation can be restored by a simple reset/rewrite operation. Soft errors can occur in digital and analog circuits, transmission lines, and magnetic storage. When a high-energy particle interacts with the semiconductor substrate, it generates many electron-hole pairs. The resulting electric field in the depletion region causes a charge drift, creating current disturbance. If the charge displacement overcomes the critical charge stored in the memory cell, the stored data may flip, causing an error when it is next read. Soft errors manifest themselves as single-bit upsets (SBU) or multi-bit upsets (MBU), depending on the energy of the causative particle. An SBU occurs when only one bit is flipped by a single energetic particle; while an MBU occurs when a high energy particle flips multiple bits in a word. The rate that measures soft errors— Soft Error Rate (SER)—determines the probability of device failure due to energetic particles. Since soft errors are random, the occurrence of soft errors doesn’t define reliability but rather the rate of failure of the memory.

Effect of radiation inside a MOS transistor

TECH REPORT Causes of Soft Errors ALPHA PARTICLES Alpha particles are emitted by radioactive nuclei in a process called alpha decay. Alpha particles have kinetic energies of a few MeV and are the direct cause of soft errors in semiconductor memories. They have a dense layer of charge and create electron-hole pairs as they pass through a substrate. If the disturbance is strong enough, a bit will flip. This lasts only for a fraction of a nanosecond, and hence is very hard to detect. Low-energy alpha particles are generated by the radioactive decay of trace amounts of Uranium-238, and Thorium-232 present in mold compounds, packages, and other assembly materials. However it’s nearly impossible to maintain the ideal material purity (less than 0.001 counts per hour per cm2) needed for reliable performance of most circuits. Small amounts of epoxy can reduce the incidence of soft errors by shielding the chip from alpha radiation. COSMIC RAYS Manufacturers have managed to control contaminants emitting alpha particles, but they have been unable to counter cosmic radiation. In fact, cosmic rays are the likeliest cause of soft errors in modern semiconductors, since radioactive contaminants have been largely controlled. The primary particles of the cosmic rays don’t usually reach the earth’s surface. However, they do

create a stream of energetic secondary particles, mostly energetic neutrons. While neutrons are uncharged and hence can’t cause soft errors, they can be captured by the nucleus in a chip, an event that can result in alpha particles. Cosmic radiation increases with altitude due to a lower shielding effect of the atmosphere. In addition, modules used at the Poles are also highly susceptible to soft errors for the same reason. To reduce soft errors, modules used in high exposure applications undergo a special process called Radiation Hardening. THERMAL NEUTRONS Neutrons void of kinetic energy are an important source of soft errors due to neutron capture reactions. The capture of a thermal neutron by a Boron isotope (10B) nucleus, found in large quantities in Boronphsophosilicate glass dielectric layers, emits an alpha particle, Lithium nucleus, and gamma ray. Either the Alpha particle or the Lithium nucleus can cause a soft error. Thermal neutrons are especially important for medical electronics used in cancer radiation therapy. The neutrons combined with the photon beam used in treatment result in a thermal neutron flux that generates a very high rate of soft errors. However, thermal neutrons aren’t a major cause of soft errors nowadays, since manufacturers eliminated borated dielectrics by the 150nm process node.

Mitigating Soft Errors Soft errors can be avoided by improving process technology and memory cell layout, system-level changes, and changing chip design and architecture.

Improving in Process Technology and Memory Cell Layout The reliability of a memory device can be enhanced by increasing the critical charge stored in the memory cell. The resistance of a device to soft errors can also be increased by using a process technology that reduces the thickness of diffusion. This reduces the amount of time a charge particle spends in a memory cell. A triple-well architecture can also be used to drift charges away from the active region. This process creates an opposite electric field with respect to the NMOSdepletion region and forces charges into the substrate. It only acts when a soft error occurs in the NMOS region.

System-level Mitigation At the system-level, designers can prevent the effect of soft errors by using

external error correction code (ECC) logic. In this technique, the user employs additional memory chips with parity bits for error detection and correction by. As expected, system-level mitigation is expensive and also adds more complexity to the system and its software.

Changes in Chip Design and Architecture This is the best way to combat soft errors. Chip designers can mitigate soft errors by using Error Correction Code (ECC). During a write operation, the ECC encoder algorithm includes parity bits with every addressable word of data stored in the memory. During a read operation, the ECC detection algorithm uses parity bits to determine whether any of the data bits have changed. If there is single-bit error, the ECC correction algorithm determines the location of the concerned bit. It can then facilitate error correction by flipping the data bit back to its complementary value. ECC alone, however, cannot address multi-bit upsets (MBU). For these,

SOFT ERRORS CAN OCCUR IN DIGITAL AND ANALOG CIRCUITS, TRANSMISSION LINES, AND MAGNETIC STORAGE.

TECH REPORT COSMIC RAYS ARE THE LIKELIEST CAUSE OF SOFT ERRORS IN MODERN SEMICONDUCTORS, SINCE RADIOACTIVE CONTAMINANTS HAVE BEEN LARGELY CONTROLLED.

designers have to implement bit interleaving. This technique arranges bit lines such that physically adjacent bits are mapped to different word registers. The bit-interleave distance separates two consecutive bits mapped to the same word register. If the bit-interleave distance is greater than the spread of a multi-cell hit, it results in single bit upset (SBUs) in multiple words rather than a multi-bit upset (MBU) in a single word. Typical bit-interleave distance depends on the process technology. Neutron testing is performed with a subsequent physical MBU analysis to determine the safe interleaving distance for each process technology node. In a bit-interleaved memory, single-bit error correction algorithm can be used to detect and correct all errors. The ECC algorithm applies only to the copy of the affected word of data. The data as it resides in memory still contains the flipped bit. If this flipped bit in memory remains uncorrected, exposure to another bit flipping in the same word of data can result in a multi-bit upset. It is important, therefore, that the ECC logic indicates the occurrence and

correction of a single-bit upset. The system can then use this information to recognize the event and writeback corrected data. This technique is known as memory scrubbing. With semiconductor chips being manufactured on shrinking process nodes, the risk of soft errors is increasing. Hence, many experts expect soft errors to be a limiting factor to continued shrinking unless new technology is developed that overcomes soft errors. Furthermore, with technology entering more spheres of human life, the need for reliability is bound to increase. This trend increases the need for on-chip Error Correcting Code (ECC) for memory modules. All major memory manufacturers have started releasing chips with on-chip ECC to meet the demand for high reliability memories. Given the high-performance applications that SRAM devices are used for, error correcting capabilities are a must for SRAMs. Cypress, the world leader in SRAMs, has a family of ultrareliable Asynchronous SRAMs with on-chip ECC and bit interleaving.

GRAND PRIZE

NXP Logic Presents Clemens Valens

The

Big

I.D.E.A.

2015 International Design Engineering Award

oin NXP and Mouser in the 2015 Big I.D.E.A., a design contest featuring NXPâ&#x20AC;&#x2122;s unique product line-up across the spectrum,

including Dual Configurable Logic, Smart Analog, MOSFETs, and Power. Everyone has a chance to win thousands of dollars worth of prizes, with awards at every level of the competition.

Entry Phase

Submission Phase

Completion Phase

Winners Announced

January 1

March 1

April 15

August 1

JANUARY 1 - ENTRY PHASE » Fill in and submit questionnaire. (Special bonus drawing for entries before March 15. Five contestants will win prizes worth $100 each.) » Advance to the Submission Phase. Click here to register and start the contest! http://convergencepromotions.com/TheBigIdea.html

MARCH 1 - SUBMISSION PHASE » Contestants will produce a schematic using NXP’s products. (Special bonus drawing for schematics before April 15. Ten contestants win prizes worth $200 each.) » Selected contestants will advance to the Completion Phase. Click here to view the Submission Phase rules and instructions. https://www.youtube.com/watch?x-yt-ts=1421782837&x-yt-cl=84359240&v=LlJOa-QR45I

APRIL 15 - COMPLETION PHASE » Design kits will be sent to contestants selected from the Submission Phase. » Entries must be submitted for judging by June 30.

AUGUST 1 - WINNERS ANNOUNCED » GRAND PRIZE: $3000 Prize Value » FIRST PLACE: $2000 Prize Value » SECOND PLACE: $1500 Prize Value » THIRD PLACE: $1000 Prize Value » HONORABLE MENTION: $500 Prize Value

New RUGGED Industrial-Grade

TRANSFORMS the Maker Movement By Glenn ImObersteg Convergence Promotions

COVER STORY

The Raspberry Piâ&#x201E;˘, Banana Pi, Beagle Board, and Panda Board have opened up a wealth of new resources for students and DIY-ers interested in electronic design. Bridging the gap between products built for hobby applications and those used in mainstream, industrial, or commercial products has been dauntingâ&#x20AC;&#x201D;until now. This article introduces a new generation of single-board computer (SBC) that has been designed for engineers searching for the simplicity and programmability of a Raspberry Pi and Beagle Board in a production-ready, industrialgrade SBC called the Boxer Board.

The Life of Pi Raspberry Pi was conceived in 2006 by Raspberry Pi Foundation Trustee, Eben Upton, and an assemblage of teachers, academics, and computer enthusiasts with the intent of devising a simple computer to inspire students. The 2012 product launch was met with instant acclaim and success; one distributor, Premier Farnell, sold out within a few minutes, and another, RS Components, took over 100,000 pre-orders on day one.

Send in the Clones The instant success of Raspberry Pi quickly spawned a number of clones, including the Banana Pi, Arduino™, Beagle Board, Panda Board, and the rest of the animal kingdom and new food groups. All of these new boards were similar in their low-cost platform designs and they all targeted the student, DIY, and hobby markets.

Trying on Capes and Hats One of the reasons for the popularity of the Raspberry Pi and Beagle Board has always been the ability to attach physical, application-specific hardware to the GPIO (General Purpose Input/ Output) connector. An entire cottage industry spawned from supporting hundreds of boards and add-ons, including buttons, LCDs, LEDs, sensors, and more. Recently, the fashionable HATs (Hardware Attached on Top) joined the family, even amidst the controversy

that many developers claim the idea is borrowed from BeagleBone capes.

DIY and Student Modules: Not Ready for Prime Time Sales of Raspberry Pi are edging towards the five million mark, and the lure of lowcost boards, easy programmability, and a plethora of accessories is undeniable. The popularity of these modules makes a convincing argument for developing ‘real-life’ projects using one of the boards discussed here, if you can overcome the dichotomy between student applications and real-world applications in the industrial, medical and aerospace industries. There are three primary reasons why the hobby modules will not be able to successfully make that leap: Sustainability and Continuity of Supply Will today’s hobby boards be available in quantity in five or ten years when you need to do a product update? The chances are that you won’t be making those decisions. If you are a typical engineer, you will have changed jobs 2.5 times (Google’s average for engineering job life-span), and if you have used a Raspberry Pi 1 or 2, or B, or B+ in an OEM application, what obstacles—such as inventory and technical support—will your successors have to contend with in a redesign? The solution is clear: for a product to be a valid solution in the embedded market, it needs to have continuity of supply, component control, and obsolescence management.

For a product to be a valid solution in the embedded market, it needs to have continuity of supply, component control, and obsolescence management.

COVER STORY Engineering Support The professional engineering community will never be able to replicate the depth of enthusiasm that the foundations and communities offer their colleagues in design and applications support, products, and hardware and software fixes. However, this enthusiasm can’t replace the 24-hour manufacturer hotlines and field application engineers that many manufacturers employ to provide customer support worldwide. Certification and Quality Control Engineers designing applications from IoT to avionics have to meet the strictest standards, such as quality (ISO 9001) or environmental management (EN ISO 14001) standards, in addition to certification for every industry the product will be used.

Crossing the Great Divide How can you decide between the functionality, programmability, easy accessibility to peripherals, and low cost of the DIY modules versus a productionready, industrial-grade reliable product? Now you can, and we have discovered it is possible to have your pie and eat it too. TQ-Group has designed a board with the TI Sitara™ AM3352 that is simple to program, flexible, affordable, and manufactured to the strictest environmental and quality management standards. Certified for medical, aviation, automotive, and other OEM applications, and backed by a team of FAEs in Europe and North America, this board is rugged, industrial-grade, and productionready. We call it the Boxer Board.

THE IMPORTANCE OF SUSTAINABILITY: A Tale of Three CPUs Consider the following adages: • Design cycles are measured in years • Engineers get really attached to their devices • MCUs take on a life of their own long after they’re designed into applications The following conversation (or urban myth?) from a few years ago is a classic illustration of the importance of continuity of supply; a Boeing engineer in the late 1990’s remarked that a Boeing 777 aircraft had three redundant flight computers, each fitted with Intel 486, Motorola 68K, and AMD 29K processors, and each set up in a voting scheme to compensate for hardware and software errors. Although there was a debate about whether the third CPU was an Intel i960 or i860, the fact is—all of these chips had been out of production for more than a decade. They had firewalled software teams to develop separate code bases for each CPU so that application level bugs would not be replicated across all three architectures, which feed into the voting system. With this level of complexity, there was no way that this system was going to be re-designed for quite some time. The moral of this tale is that for a product to be a valid solution in the embedded market, it needs continuity of supply, component control and obsolescence management.

The new Boxer Board SBC from TQ combines the simplicity of the BeagleBone Black with a rugged design for industrial applications. The new Boxer Board (TQ SBCa335x) was designed from specifications and requirements for a customer who manufactures water treatment plants for emerging nations. The requirements for the development were: • Ease of programming and low-cost • Industry certifications for in-plant operations • Guarantee of long-term availability • Continuous and reliable operation at high temperatures

Dominik Mücke and Jens Linke from TQ-Systems GmbH

As a solution, engineers Dominik Mücke and Jens Linke from TQ-Systems GmbH in Munich, Germany, developed the SBCa335x—an SBC using the same processor family as the BeagleBone Black with pin-compatible headers for the BeagleBone Black Capes and Raspberry Pi B+ Capes and Hats.

Nick-named the ‘Boxer Board’ by Convergence Promotions LLC, the North American sales and distribution company for TQ-Group, the SBCa335x debuted at Embedded World in late February 2015 and received instant acclaim. The Boxer Board is based on the Sitara™ AM3352 (optional 3354) processor (800 MHz ARM Cortex™-A8 Core) from Texas Instruments. Its compact and rugged design of only 4.8” (12 cm) by 3.2” (8 cm), temperature range of -20°C to +70°C, and low-power consumption (typ. 2W), makes the Boxer Board suitable for industrial applications in the smallest of spaces. It provides pincompatibility with the Raspberry Pi B+, so adding capes and hats is a breeze.

Interfaces for Even the Most Demanding Applications The Boxer Board has an impressive number and variety of interfaces including: • 2x Gigabit Ethernet, 2x USB (Host and OTG) • CAN and WiFi (2.4 GHz b/g/n) and Bluetooth 4.0 • 1x HDMI, micro SD and access to UART, SPI, I2C, 20 GPIOs • 6x 12-bit ADC channels, and more This array of interfaces makes the Boxer Board applicable for a wide range of industrial and medical applications particularly for the IoT and M2M markets. Its compatible interface to Raspberry Pi B+ Capes and Hats provides added flexibility and speeds time-to-market.

COVER STORY Priced under $100 with WiFi and Bluetooth Even with WiFi, Bluetooth, and a number of other interfaces not included with Raspberry Pi or BeagleBone Black, the production-ready, industrial-grade Boxer Board with the Sitara™ AM3352 will still retail for under $100.

Boxer Board Specification Microprocessor

AM3352, AM3354 (on request) 256MB DDR3L-SDRAM, 512KB on request

Memory

16MB NOR-Flash, Up to 16MB on request 1x Micro-SD-Card 1x CAN (3.3V, not galvanically separated) ISO 11898 2x 10/100/1000 Mbit (LS switch) IEEE 1588 1x I²C

System Interfaces

1x SPI 1x UART (UART to TTL Serial Cable 3.3V) 2x USB 1x 2.0 OTG (Micro USB), 1x USB 2.0 HOST (USB Typ A) 1x WiFi – 2.4 GHz IEEE Std 802.11 b/g/n 1x Bluetooth 4.0 6x 12-bit ADC channels (1.8V MAX)

Other Interfaces & Busses

20x GPIO 16-bit data bus width CPU JTAG debugging interface

General Dimensions

120 mm x 80 mm

Audio

1x Audio (Headphone, Mic In, Line In, Line Out)

RTC

Yes

Reset Button

Yes

Temperature Sensor

Yes, with 2KByte EEPROM

System Connector

Pinstrip (80 pins), including Raspberry Pi B+ compatible pinstrip

Temperature Range

-20°C…+70°C

Operating Systems

Linux 3.14, QNX, WEC 2013

WHAT’S IN A NAME? Raspberry Pi: “A reference to a fruit naming tradition in the old days of microcomputers. A lot of computer companies were named after fruit. There’s Tangerine Computer Systems, Apricot Computers, and the old British company Acorn, which is a family of fruit. The name Pi came about because originally they were going to produce a computer that could only really run Python. So the Pi in there is for Python”.* Beagle Board: Named for “Boris” the Beagle Boxer Board: Named for the author’s dog “Winston,” an 85-pound Boxer. *Techspot interview with Eben Upton, by Jose Vilches on May 22, 2012

Block Diagram SBCa335x

BSPs and Operating Systems You Can Work With The Boxer Board runs on Linux, QNX and WEC 2013, (with VXWorks available on request) and can be ordered in two memory versions (256 MB DDR3L SDRAM and 512 MB DDR3L SDRAM).

Certification for Your Applications and Continuity of Supply Until 2025 As with all of the TQ products, quality management is of major importance (TQ stands for â&#x20AC;&#x2DC;Technology in Qualityâ&#x20AC;&#x2122;). TQ-Group is certified in accordance with ISO 9001 (Quality Management), ISO 14001 (Environmental Management), EN 9100 (Civil Aviation), ISO 13485 and MDD (Medical Technology), as well as ISO/TS 16949 (Automotive).

Summary The legacy of Raspberry Pi and other hobby-level modules will be that it revolutionized the board industry by making low-cost and easy-to-design modules and feature-rich accessories available to millions worldwide. The Boxer Board is the next step in the evolution of these boards from hobbylevel to industrial-grade solutions for the thousands of embedded engineers who started as students on the hobby platforms and have graduated to developing embedded applications for IoT, industrial, medical, automotive and other industries. The Boxer Board will be available in May 2015 from TQ-Systems (www.TQ-Group.com) www.TQ-Group.com in EMEA and from Convergence Promotions (www.embeddedmodules.net) www.embeddedmodules.net in North America.

COVER STORY BEAGLEBONE BLACK

RASPBERRY PI

TQ BOXER BOARD

1GHz TI Sitara AM3359 ARM Cortex-A8

700 MHz ARM1176JZFS

800 MHz TI Sitara AM3352 ARM Cortex-A8

512MB DDR3L

512MB SDRAM

256MB DDR3L, Optional 512MB/1GB

2GB on-board eMMC, Micro SD

16MB NOR Flash, Micro SD

1x USB Host, 1x MiniUSB Client, 1x 10/100 Mbps Ethernet

2x USB Hosts, 1x MicroUSB Power, 1x 10/100 Mbps Ethernet, RPi camera connector

2x Ethernet 10/100/1000, 2x USB (Host & OTG), 1x CAN, 1x SPI, 1x I2C, 6x 12-bit ADC

WiFi/Bluetooth

2.4GHz 802.11 b/g/n and Bluetooth 4.0

GPIO Capability

65 Pins

8 Pins

20 pins

CPU JTAG debug connector

Operating Systems

Angstrom (Default), Ubuntu, Android, ArchLinux, Gentoo, Minix, RISC OS, others…

Raspbian (Recommended), Ubuntu, Android, ArchLinux, FreeBSD, Fedora, RISC OS, others…

Linux 3.14, QNX & WEC2013

Video Connections

1x Micro-HDMI

1x HDMI, 1x Composite

1x mini HDMI

1280×1024 (5:4), 1024×768 (4:3), 1280×720 (16:9), 1440×900 (16:10): all at 16-bit

Extensive from 640×350 up to 1920×1200, this includes 1080p

WXGA 1366x768

Stereo over HDMI

Stereo over HDMI, Stereo from 3.5mm jack

210-460mA @ 5V under varying conditions

150-350mA @ 5V under varying conditions

3x AA/AAA, 5V Micro USB. 750mA @ 5V under varying conditions (WiFi and Bluetooth)

0°C to +70°C temperature range

Untested -25°C to +80°C temperature range

Rugged construction for industrial use and -20°C to +70°C temperature range

ISO 9001, EN 9100 (Aviation), ISO 13485 (Medical technology), ISO 16949 (automotive)

Size

3.4x2.1 inches

3.4x2.2 inches

4.8x3.2 inches

Price

$50

$35

Sub- $100* *Price subject to change

Processor RAM Storage

Peripherals

JTAG

Supported Resolutions

Audio

Power Draw

Environmental

Certification

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