Tuesday, October 23, 2018

The Health and Economical Benefits of Solid-State Cooking

MACOM, October 23, 2018

RFE Diagram.PNGThe ability to generate and amplify RF signals is nothing new – but solid-state RF energy has enormous potential beyond data transmission applications. As companies like MACOM and collaborative organizations such as the RF Energy Alliance (RFEA) continue to pioneer and develop this technology, enabling greater efficiency and control than previously possible with conventional technologies, the full potential of this technology for mass-market applications is beginning to take form.

Microwave cooking is one application that is already being radically transformed with solid-state RF energy, enabling healthier eating and broad economical benefits. Solid-state RF energy transistors generate hyper-accurate, controlled energy fields that are extremely responsive to the controller, resulting in optimal and precise use and distribution of RF energy. This offers benefits unavailable via alternate solutions, including lower-voltage drive, high efficiency, semiconductor-type reliability, a smaller form factor and a solid-state electronics footprint. Perhaps the most compelling benefit is the power-agility and hyper-precision enabled by this technology, yielding even energy distribution, unprecedented process control range and fast adaption to changing load conditions, not to mention a lifespan of more than 10 years.

...more

Thursday, September 13, 2018

Giving voice to the elderly

XMOS, September 13, 2018

Voice-enabled technologies will transform the health and happiness of the elderly.

The UN predicts a 56% rise in the number of people aged 60 years or over, taking us from over 900 million in 2015 to nearly 1.5 billion in 2030.The world’s population is changing. Our demographic is aging. And this could well be the defining issue of our time. An aging population creates a burden on health systems and individual households. Family members, clinicians, and assisted care providers will need a new generation of technology platforms to help them stay informed, coordinated, and most importantly, connected.

The social care system is facing a mountain of challenges and it can’t cope with a sustained upswing in the number of senior people and adults living with chronic illnesses.

Whether living at home or in an assisted facility, help may come from an unexpected source – technology. Speech recognition and voice-enabled devices make technology accessible to all. There’s no need to tap a keyboard or figure out how to work the remote control, you simply talk to the device from across the room. A voice-controlled device can empower a formerly ‘dis-empowered’ user. It can ease pressure on caregivers, becoming a companion and digital assistant. Of course it’s not a replacement for human interaction, but rather a meaningful addition.

...more

Thursday, June 21, 2018

Why 50 Ohms?

Ryan Foster, NuWaves Engineering, June 21, 2018

A common concern for radio frequency design engineers is providing sufficient margin in a module or system to survive the real-world application in which their work will eventually operate. Our engineering team is constantly dealing with the trade-offs of meeting the myriad of customer specifications while ensuring that our designs are robust enough to survive the unpredictable reality of fielding those designs. For instance, it is one thing to design an amplifier that operates in the perfectly controlled environment of a laboratory, but then connect that amplifier to an antenna which looks like a nice comfortable perch to a bird and you have a completely different story. One of the measuring sticks that engineers utilize to judge a system or modules robustness is to test is ability to survive a mis-matched load. Voltage Standing Wave Ratio (VSWR) is the most common method for quantifying the ability of a 50-ohm matched module to withstand the mis-matches that we all know it will experience when it is eventually fielded, with an output VSWR rating of 10:1 being common in the industry. But wait, where did that 50-ohms starting point come from?

...more

Monday, April 9, 2018

Common Mode Overview and Reduction Guide

MTE, April 9, 2018

Understanding the creation, effects, and how to reduce common mode over voltage.

What is Common Mode?

To start off, common mode is bad. Common mode voltage is created by Variable Frequency Drives (VFDs) that serve as a way of controlling the speed of AC motors by varying the frequency of the power source using pulse width modulation (PWM). This is done by switching the transistors, IGBTs, or thyristors, on and off continuously.

The continuous generation of power pulses from VFDs prevents a smooth sinewave from being produced, which at any point is at a sum of zero (see Fig.1). Instead, the waveforms produced result in a sum at any point that is not always zero (see Fig.2). The result is damaging common mode over voltage, which can cause devastating effects to your equipment.

Destructive Effects of Common Mode Over Voltage

Common mode problems occur outside of the VFD, which is why they are difficult to diagnose.  The effects of common mode over voltage are extremely problematic for everyday operations. These problems negatively effect your bottom line, creating the need to replace equipment, increase repair costs, and can result in the loss of production.

...more

Tuesday, January 9, 2018

Stepper Motor Voltage Explained

Elinco-JPC, January 09, 2018

Stepper motor ‘voltage’ is an often confusing subject. Many motor drivers use widely varying bus voltages to operate stepper motors. In fact, identical stepper motors can be (and commonly are) operated at greatly different voltages in different systems. How can the same motor be run at different voltages? How does the bus voltage impact the stepper motor’s performance?

...more