Electronics for the transconductance amplifier designed by Orchid Technologies enables high-speed detection of plaque buildup in veins and arteries. Photo courtesy of Orchid Technologies Engineering & Consulting, Inc.

Company designs components for medical industry, renewable energy , and more

The medical industry is known for its emphasis on standards and regulations that must be followed, depending on the type of device being designed. Designers must demonstrate, through adequate testing and documentation, that product requirements are being met.

The FDA and similar bodies in the countries have various rules, regulations and guidance. Many of these requirements are fulfilled by adhering to appropriate third-party standards—published by organizations such as IEC, ISO, AAMI, and UL—for a given device.

“With regard to medical electronics, there’s certainly been a trend toward more regulation and increasing scrutiny about the design process as a whole,” said Paul Nickelsberg, president and senior engineer at Orchid Technologies Engineering and Consulting, Inc., a Maynard, MA company that specialized in the design, product development, and production of high-tech custom electronics. “That represents opportunities and difficulties for organizations that are trying to sell or bring to market medical devices.”

Nickelsberg can attest to the huge panorama of applications that have opened up for medical electronic devices that do things like measure temperature and pressure, or turn a pump, or radiate something with energy. “It’s such a wide field,” he says. “We’ve worked on everything from CT scanners to infrared light detection equipment. Some of them are very time and simple, and some of them are absolutely enormous and full of all kinds of regulation.”

One of Orchid’s medical projects was the design of a high-speed transconductance amplifier, a device that detects buildup of plaque in veins and arteries by sensing the tiniest variations in fluorescent light levels inside the human body. The amplifier system is excited by the laser light source and is reported to be capable of detecting infrared light levels below -40dbm, with a frequency response flat to 35 KHz. Orchid provided multiple iterations of the system design, helping its client through the proof-of-concept phases through a technically challenging project.

“A transconductance amplifier is useful because it is capable of reading very low levels of light or turning low levels of light to a usable electronic signal,” explains Nickelsberg. “And you can imagine that there are all kinds of applications where low levels of light are used for things like, in this case, sensing the reflectance of plaque. It’s an amplifier that would be used to detect those very low levels of light—like nanowatts or pico watts—almost to the point of single photons. There are all kinds of applications for it, including CT scanners, which work with very low levels of X-ray light.”

Positioned on the end of a rotating detector mechanism, the front-end uses slip-rings to carry power and encoded data signals to stationary computer equipment. It also makes use of custom encoded, serial data-communications protocols to pass data and control signals between stationary and rotating equipment. A major part of Orchid’s custom design work involved selecting the appropriate slip ring and data communications technology. The company also employed analog circuit modeling techniques, and signal-source fixturing to design what it called “a reliable, accurate, and highly-repeatable transconductance amplifier.” In addition, Orchid designed digital electronics that mad it possible to digitize the data that came from the amplifier. “All of this was used in a very early research tool that proved the science,” said Nickelsberg.

Using specialized software to carefully simulate how a component, such as an amplifier, would work plays an important role in engineering. But there are times, according to Nickelsberg, when simulation doesn’t quite tell the whole story because of an application’s unique operating environment. In those situations, he says, there’s nothing like actually building a rough prototype and trying it out. “Often, in an amplifier that’s as sensitive as this particular one, things like noise, shielding and power supply quality affect the operation of the amplifier so  much that it goes beyond what we can do with just a plain simulation,” he explains. “So it’s nice to see the [prototype] working and actually tweak it right there on the spot.”

Orchid serves high-growth markets in addition to the medical industry, including avionics, power, consumer computing, and industrial applications. One of its specialties is redesigning obsolete equipment. The company has also established a foothold in greentech, designing electrical components for renewable energy technologies. “We’ve done motor controllers in the space of wind energy, and that’s been very interestinig,” says Nickelsberg. “We’ve also been doing some work [involving] converters and things for the photovoltaic (PV) solar industry, because there are a lot of possibilities there.”

Renewable Energy Systems Provide High Efficiency: Brushless DC Motor Controllers help save fossil fuels

Brushless DC Motor Controller

This low cost, miniature, brushless DC motor controller packs enormous power into a tiny electronics package. Designed to drive 48-Volt brushless DC motors up to 1400 watts, this miniature controller may be the smallest in its class. Small physical sizes make it possible to develop high torque and operating speeds when overall product size and weight are application limited.

Miniature Power Electronics

Orchid Technologies combined cost-sensitive engineering with precision power electronics to craft an efficient, high-performing, three-phase power-output stage. Working closely with silicon vendors, Orchid carefully selected FET output stage devices while perfectly matching drive and sensing technology characteristics.

ST Micro Electronics ST7MC Microcontroller

Orchid selected an ST7MC microcontroller as the brains of this brushless DC motor controller. The ST7MC's feature-rich complement of flash program store, static RAM, Eeprom, patented motor controller, timers, analog-to-digital conversion circuitry, and robust processor reliability controls make the ST7MC a perfect fit in the motor control marketplace. The ST7MC's patented motor control subsystem provides a highly cost effective method to control many different types of brushless DC motors. Sensor and sensorless motors, 120- and 60-degree styles are a11 supported.

Motor Control from Orchid Technologies

The development of custom electronics technology solutions for our OEM clients is Orchid's entire business. High-performance motion controller designs with rapid design cycles, demanding technical requirements, and unforgiving schedules set us apart.