Bench Talk

Last month, I received a customer complaint about high-frequency spikes on the output of a DC/DC converter. I first reviewed the part’s schematic locations, and all of the necessary noise filtering was in place. High-quality input bypass caps were right at the power train, the correct main waveform snubber was in place, and the output had the needed high-frequency bypass caps.

Designing power supplies for factory-automation equipment such as programmable logic controllers , transmitters, automation machinery and human machine interfaces can come with a lot of challenges. Even as processing power continues to increase, printed circuit board (PCB) area and overall equipment sizes tend to remain the same. To meet these strict space constraints, power-supply designs should be compact but also operate efficiently and quietly; heat and noise are absolutely not permissible. In addition, there are multiple industrial power-supply requirements, including a wide-input voltage range, a small solution size and the ability to operate at a high temperature range. Power-supply designers must keep component counts and costs down while providing a reliable solution that doesn’t require a lot of debugging. So starting with an integrated and robust device is a high priority.

As High Intensity Discharge (HID, xenon) and LED technologies are the only truly modern vehicle light sources, unless you own a luxury vehicle chances are you (like me) are missing out actually being able to see well into the night. The difference between what these two technologies and 50-year-old quartz-halogen bulbs deliver is like night and day. Fortunately, thanks to the dramatic advances and reduced cost of high-brightness LEDs, high-performance forward lighting is now about to be available to the rest of us.

Choosing temperature-sensing products may seem trivial, but with the wide variety of products available, this task can be quite daunting. In this blog post, I’ll present four types of temperature sensors – resistance temperature detectors (RTDs), thermocouples, thermistors and integrated circuit (IC) sensors with digital and analog interfaces – and discusses the pros and cons of each.

A little while ago, Texas Instruments (TI) launched their new MSP432 family of microcontrollers. Along with the new silicon, there is also a new LaunchPad development kit. Continuing the tradition from the MSP430, the new chips are very affordable while packing in professional grade features and very impressive energy sipping performance.

As an editor I’ve been on the receiving end of a lot of specmanship, which is why I always look to datasheets, though meaningful comparisons of seemingly similar MCUs between different vendors are hard to construct, especially since overall energy consumption is so application specific. As Markus Levy of the Embedded Microprocessor Benchmark Consortium (EEMBC) remarked to me last week, “Datasheets don’t lie, they just present [information] the way they want to present it.”