New Products: May 2013

Posted on 2013/05/15 by Circuit Cellar Staff

iC-Haus iC-TW8

The iC-TW8 is a high-resolution signal processor designed to evaluate sine/cosine sensors. Its automatic functions help minimize angular errors and jitters. The processor can be used for initial, push-button calibration and to permanently adapt signal-path parameters during operation. The angular position is calculated at a programmable resolution of up to 65,536 increments per input cycle and output as an indexed incremental signal. A 32-bit word, which includes the counted cycles, is available through the SPI.

As an application-specific DSP, the iC-TW8 has two ADCs that simultaneously sample at a 250-ksps rate, fast CORDIC algorithms, special signal filters, and an analog front end with differential programmable gate amplifier (PGA) inputs that accepts typical magnetic sensor signals from 20 mVPP and up. Signal frequencies of up to 125 kHz enable high rotary and linear speeds for position measuring devices and are processed at a 24-µs constant latency period.

The device’s 12-bit measurement accuracy works with one button press. Measuring tools are not required. The iC-TW8 independently acquires information about the signal corrections needed for offset, amplitude, and phase errors and stores them in an external EEPROM.

The iC-TW8 has two configuration modes. Preset functions and interpolation factors can be retrieved through pins and the device can be calibrated with a button push. No programming is required for initial operation.

The device’s functions—including an AB output divider for fractional interpolation, an advanced signal filter to reduce jitter, a table to compensate for signal distortion, and configurable monitors for errors and signal quality—can be accessed when the serial interfaces are used. Typical applications include magnetic linear displacement measuring systems, optical linear scales, programmable magnetic/optical incremental encoders, high-resolution absolute/incremental angle sensors with on-axis, Hall scanning, and the general evaluation of sine/cosine signals (e.g., PC measuring cards for 1 VPP and 11 µAPP).

The iC-TW8 operates on a 3.1-to-5.5-V single-ended supply within a –40°C-to-125°C extended operating temperature range. It comes in a 48-pin QFN package that requires 7 mm × 7 mm of board space. A ready-to-operate demo board is available for evaluation. An optional PC operating program, in other words, a GUI, can be connected with a USB adapter.

The iC-TW8 costs $7.69 in 1,000-unit quantities.

iC-Haus GmbH

www.ichaus.com

ULTRASOUND RECEIVERS

Analog Devices AD9675

The AD9675 and the AD9674 are the latest additions to Analog Devices’s octal ultrasound receiver portfolio. The devices and are pin compatible with the AD9670/AD9671.

The AD9675 is an eight-channel ultrasound analog front end (AFE) with an on-chip radio frequency (RF) decimator and Analog Devices’s JESD204B serial interface. It is designed for mid- to high-end portable and cart-based medical and industrial ultrasound systems. The device integrates eight channels of a low-noise amplifier, a variable-gain amplifier, an anti-aliasing filter, and a 14-bit ADC with a 125-MSPS sample rate and a 75-dB signal-to-noise ratio (SNR) performance for enhanced ultrasound image quality. The on-chip RF decimator enables the ADC to be oversampled, providing increased SNR for improved image quality while maintaining lower data I/O rates. The 5-Gbps JESD204B serial interface reduces ultrasound system I/O data routing.

The AD9674 offers similar functionality, but includes a standard low-voltage differential signaling (LVDS) interface. Both devices are available in a 144-ball, 10-mm × 10-mm ball grid array (BGA) package.

The AD9674 and the AD9675 cost $62 and $68, respectively.

Analog Devices, Inc.

www.analog.com

LOW-VOLTAGE DIGITAL OUTPUT HALL-EFFECT SENSORS

Melexis MLX92212

MLX92212 digital output Hall-effect sensors are AEC-Q100-qualified devices that deliver robust, automotive-level performance. The MLX92212LSE-AAA low-hysteresis bipolar latch and the MLX92212LSE-ABA high-hysteresis unipolar switch are optimized for 2.5-to-5.5-V operation. They pair well with many low-power microcontrollers in embedded systems. The sensor and specified microcontroller can share the same power rail. The sensors’ open-drain outputs enable simple connectivity with CMOS/TTL. They exhibit minimal magnetic switch point drift over temperature (up to 150°C) or lifetime and can withstand 8 kV electrostatic discharge.

The MLX92212LSE-AAA is designed for use with multipole ring magnets or alternating magnetic fields. It is well suited for brushless DC electric motor commutation, speed sensing, and magnetic encoder applications. Typical automotive uses include anti-trap/anti-pinch window lift controls, automatic door/hatch systems, and automatic power seat positioning. The MLX92212LSE-ABA enables the use of generic/weak magnets or larger air gaps. It can be used in simple magnetic proximity sensing and interlocks in covers/hatches or ferrous-vane interrupt sensors for precise position and timing applications.

Both MLX92212 devices utilize chopper-stabilized amplifiers with switched capacitors. The CMOS technology makes this technique possible and contributes to the sensors’ low current consumption and small chip size.

The MLX92212 sensors cost $0.35 each in 5,000-unit quantities and $0.30 in 10,000-unit quantities.

Melexis Microelectronic Integrated Systems

www.melexis.com

POWERFUL SPI ADAPTERS

Byte SPI Storm

The SPI Storm 50 and the SPI Storm 10 are the latest versions of Byte Paradigm’s SPI Storm serial protocol host adapter. The adapters support serial peripheral interface (SPI), Quad-SPI, and custom serial protocols in the same USB device.

The SPI Storm 50 and the SPI Storm 10 support serial protocols and master up to 50 and 10 MHz, respectively. The SPI Storm 10 features an 8-MB memory, while the higher-end devices are equipped with a 32-MB memory.

The SPI Storm adapters enable system engineers to access, communicate, and program their digital board and digital ICs, such as field-programmable gate array (FPGA), flash memories, application-specific integrated circuit (ASIC), and

system-on-a-chip (SoC). The SPI Storm 10 is well suited for engineering schools and universities because it is a flexible, all-around access device for hands-on digital electronics. The 50- and 100-MHz versions can be used in mid- and high-end testing and debugging for telecommunications, medical electronics, and digital imaging industries.

The SPI Storm 50 and the SPI Storm 10 cost $530 and $400, respectively.

Byte Paradigm

www.byteparadigm.com

ANALOG-BASED POWER MANAGEMENT CONTROLLER WITH INTEGRATED MCU

Microchip MCP19111

The MCP19111 digitally enhanced power analog controller is a new hybrid, digital and analog power-management device. In combination with the expanded MCP87xxx family of low-figure-of-merit (FOM) MOSFETs, it supports configurable, high-efficiency DC/DC power-conversion designs for many consumer and industrial applications.

The MCP19111 controller, which operates at 4.5 to 32 V, integrates an analog-based PWM controller with a fully functional flash-based microcontroller. This integration offers the flexibility of a digital solution with the speed, performance, and resolution of an analog-based controller.

The MCP19111 devices have integrated MOSFET drivers configured for synchronous, step-down applications. The MCP87018, MCP87030, MCP87090, and MCP87130 are 25-V-rated, 1.8-, 3-, 9-, and 13-mΩ logic-level MOSFETs that are specifically optimized for switched-mode-power-supply (SMPS) applications.

The MCP19111 evaluation board includes Microchip’s high-speed MOSFETs. This evaluation board includes standard firmware, which is user-configurable through an MPLAB X IDE graphical user interface (GUI) plug-in. The combined evaluation board, GUI, and firmware enable power-supply designers to configure and evaluate the MCP19111’s performance for their target applications.

The MCP19111 controllers cost $2.81 each and the MCP87018/030/090/130 MOSFETs cost $0.28 each, all in 5,000-unit quantities.

Microchip Technology, Inc.

www.microchip.com

ELASTOMER SOCKET FOR HIGH-SPEED QFP ICs

Ironwood SG-QFE-7011

The SG-QFE-7011 is a high-performance QFP socket for 0.4-mm pitch, 128-pin QFPs. The socket is designed for a

1.6-mm × 14-mm × 14-mm package size with a 16-mm × 16-mm lead tip to tip. It operates at bandwidths up to 10 GHz with less than 1 dB of insertion loss and has a typical 20 mΩ per I/O contact resistance. The socket connects all pins with 10-GHz bandwidth on all connections. The small-footprint socket is mounted with supplied hardware on the target PCB. No soldering is required. The small footprint enables inductors, resistors, and decoupling capacitors to be placed close to the device for impedance tuning.

The SG-QFE-7011’s swivel lid has a compression screw that enables ICs to be quickly changed out. The socket features a floating compression plate to force down the QFP leads on to elastomer. A hard-stop feature is built into the compression mechanism.

The sockets are constructed with high-performance, low-inductance gold-plated embedded wire on elastomer as interconnect material between a device and a PCB. They feature a –35°C-to-100°C temperature range, a 0.15-nH pin self inductance, a 0.025-nH mutual inductance, a 0.01-pF capacitance to ground, and a 2-A per pin current capacity.

The SG-QFE-7011 costs $474.

Ironwood Electronics

www.ironwoodelectronics.com

Retro Electronics (“Retronics”): Analog, Test, & Micrcontroller Tech

Posted on 2013/02/05 by C. J. Abate

Pop quiz: What was the first microcontroller to leave the Earth? Find out the answer in Jan Buiting’s new “Retronics” webinar. Check out the video below.

The Tektronix 546B

If you read Circuit Cellar and Elektor magazines, you likely have as much passion for old-school electronics as you do for he new, cutting-edge technology you find at events such as the Embedded Systems Conference. Elektor editor Jan Buiting is well-known for his love of both new and old technology, and in his Retronics webinar series he presents some of his favorite old-school technologies.

In the video below, Jan explains how and where he found some of his retronics equipment. He also details how he fixed some of the systems and what he does with them. Examples include:

A Heathkit TC-2P Tube Checker that Jan found at lawn sale
Old audio equipment
A satellite TV receiver
An “Elektorscope” from 1977
1980s-era test equipment
And more!

CircuitCellar.com is an Elektor International Media publication.

Prevent Embedded Design Errors (CC 25th Anniversary Preview)

Posted on 2012/11/17 by C. J. Abate

Attention, electrical engineers and programmers! Our upcoming 25^thAnniversary Issue (available in early 2013) isn’t solely a look back at the history of this publication. Sure, we cover a bit of history. But the issue also features design tips, projects, interviews, and essays on topics ranging from user interface (UI) tips for designers to the future of small RAM devices, FPGAs, and 8-bit chips.

Circuit Cellar’s 25th Anniversary issue … coming in early 2013

Circuit Cellar columnist Robert Lacoste is one of the engineers whose essay will focus on present-day design tips. He explains that electrical engineering projects such as mixed-signal designs can be tedious, tricky, and exhausting. In his essay, Lacoste details 25 errors that once made will surely complicate (at best) or ruin (at worst) an embedded design project. Below are some examples and tips.

Thinking about bringing an electronics design to market? Lacoste highlights a common error many designers make.

Error 3: Not Anticipating Regulatory Constraints

Another common error is forgetting to plan for regulatory requirements from day one. Unless you’re working on a prototype that won’t ever leave your lab, there is a high probability that you will need to comply with some regulations. FCC and CE are the most common, but you’ll also find local regulations as well as product-class requirements for a broad range of products, from toys to safety devices to motor-based machines. (Refer to my article, “CE Marking in a Nutshell,” in Circuit Cellar 257 for more information.)

Let’s say you design a wireless gizmo with the U.S. market and later find that your customers want to use it in Europe. This means you lose years of work, as well as profits, because you overlooked your customers’ needs and the regulations in place in different locals.

When designing a wireless gizmo that will be used outside the U.S., having adequate information from the start will help you make good decisions. An example would be selecting a worldwide-enabled band like the ubiquitous 2.4 GHz. Similarly, don’t forget that EMC/ESD regulations require that nearly all inputs and outputs should be protected against surge transients. If you forget this, your beautiful, expensive prototype may not survive its first day at the test lab.

Watch out for errors

Here’s another common error that could derail a project. Lacoste writes:

Error 10: You Order Only One Set of Parts Before PCB Design

I love this one because I’ve done it plenty of times even though I knew the risk.

Let’s say you design your schematic, route your PCB, manufacture or order the PCB, and then order the parts to populate it. But soon thereafter you discover one of the following situations: You find that some of the required parts aren’t available. (Perhaps no distributor has them. Or maybe they’re available but you must make a minimum order of 10,000 parts and wait six months.) You learn the parts are tagged as obsolete by its manufacturer, which may not be known in advance especially if you are a small customer.

If you are serious about efficiency, you won’t have this problem because you’ll order the required parts for your prototypes in advance. But even then you might have the same issue when you need to order components for the first production batch. This one is tricky to solve, but only two solutions work. Either use only very common parts that are widely available from several sources or early on buy enough parts for a couple of years of production. Unfortunately, the latter is the only reasonable option for certain components like LCDs.

Ok, how about one more? You’ll have to check out the Anniversary Issue for the list of the other 22 errors and tips. Lacoste writes:

Error 12: You Forget About Crosstalk Between Digital and Analog Signals

Full analog designs are rare, so you have probably some noisy digital signals around your sensor input or other low-noise analog lines. Of course, you know that you must separate them as much as possible, but you can be sure that you will forget it more than once.

Let’s consider a real-world example. Some years ago, my company designed a high-tech Hi-Fi audio device. It included an on-board I²C bus linking a remote user interface. Do you know what happened? Of course, we got some audible glitches on the loudspeaker every time there was an I²C transfer. We redesigned the PCB—moving tracks and adding plenty of grounded copper pour and vias between sensitive lines and the problem was resolved. Of course we lost some weeks in between. We knew the risk, but underestimated it because nothing is as sensitive as a pair of ears. Check twice and always put guard-grounded planes between sensitive tracks and noisy ones.

Circuit Cellar’s Circuit Cellar 25^th Anniversary Issue will be available in early 2013. Stay tuned for more updates on the issue’s content.

Lacoste’s High-Speed ADC Discussion

Posted on 2012/02/13 by C. J. Abate

High-speed analog-to-digital converters can be tricky—and sometimes costly—to work with. In his Circuit Cellar 259 article, “Playing with High-Speed ADCs,” columnist Robert Lacoste provided handy tips on effectively implementing them to your advantage. He used an Analog Devices AD9265-125 as an example.

A high-speed ADC is just a part of a high-performance digitizing system.

In response to the article, a reader wrote:

“Hello, Robert. Thanks for all the articles in CC. Your High Speed ADC covered some of the concepts I have been thinking about with creating a laser range finder using Pulsed time of flight. The problem is the frequencies are in the 20 GHz for 8-mm resolution. The ADC can be very low resolution, but the sampling has to be in the 40-GHz range. The sensors need to be dark 50% of the time to get even 10-GHz response times from the crystals. So, I was wondering how do the small handheld range finders work? They are accurate to 8 mm and cost $150+. Is there a easier way to do Time of Flight? Do you know how they do this? The internet is kind of a endless trail with nothing that leads to IC’s or circuits.”

Robert provided an insightful answer:

“The short and honest answer would be ‘I don’t know,’ as I’ve never worked or inspected the internals of a laser range finder. However I’m sure that they don’t use 20Gsps+ ADC’s… I would guess that they use more some kind of time interval to voltage converters, followed by a slow but high resolution ADC. The idea is basically to charge a capacitor between the transmit and receive pulses, and to measure to voltage on the capacitor. This technique is for example used in all Agilent’s period/frequency meters: these devices measure single-shot events with a resolution down to 10ps or so, and don’t include anything faster than a 100MHz clock. Look for ‘dual Vernier interpolation’ techniques. On the laser range side, I dug a little on the net and found this link which seems to confirm this assumption: http://herkules.oulu.fi/isbn9514269667/html/c305.html. There is at least one company who develops custom chips adequate for this job: http://www.acam.de/index.php?id=149. See there: www.acam.de/products/time-to-digital-converters/applications/laser-distance-meters/.”

You can purchase the issue in which this article appears in the CC Webshop.

Issue 259: An Interview with Chris Gammell

Posted on 2012/02/05 by C. J. Abate

In Circuit Cellar February 2012 (Issue 259), we feature a recent interview with Chris Gammell, the multitalented engineer who co-hosts The Amp Hour with Dave Jones. Chris tells us about his designs, workspace, podcasts, and much more. Here’s an excerpt:

NAN: What was the impetus for starting your radio show, The Amp Hour (www.theamphour.com) which you co-host with Dave Jones of the EEVblog?

CHRIS: I’m a member of the online community reddit, and actually an administrator of the ECE sub-group (http://reddit.com/r/ECE). Two years ago, there was a request on the site for podcasts and blogs featuring electronics, because the submitter wanted to learn more while in the car and on their bike. I tried a podcast by myself and it was dreadful. But once I posted it, Dave Jones happened to hear it and suggested we give it a shot together. We didn’t have much of a plan at first, just to get on the line and shoot the breeze for an hour or so. After the first two episodes, we began soliciting our listeners and Dave’s regular viewers for a name for the show. One of our listeners suggested “The Amp Hour” and it’s been roughly an hour-long show every week since. It’s one of my favorite times of the week and I’m so glad I have been able to continue doing the show, 70-some episodes later. If your readers haven’t had a chance to listen, I hope they will at some point in the future. I personally think the best time to listen to the show is on the way to or from work, or while sitting at your bench soldering.

NAN: Some recent Amp Hour interviewees included: Jeff Keyzer of the blog MightyOhm.com (December 2011); John Edmond, co-founder and director of Advanced Optoelectronics Technology at Cree (November 2011); and Joe Grand, president of Grand Idea Studio and a former member of the legendary hacker collective L0pht Heavy Industries (September 2011). How do you decide who to feature on the show? Can you tell us who has been your favorite or most memorable guest?

CHRIS: Your embedded programming readers out there undoubtedly know Jack Ganssle, who was a guest on our show. It was a ton of fun trading stories with him and hearing how the computer industry used to be driven by the demands of the… ahem…online adult industry. But really, all of our guests have been amazing. We choose guests who not only have interesting stories and work but also can chat about the weekly news and who enjoy electronics. I’m sure a couple of members of the Circuit Cellar audience will be in our sights as potential guests in the future!

To read the entire article, go to CC-Access.