Medical product design and manufacturing is not for the weak of heart. There are critical demands for safety and reliability and lengthy cycles for product qualification. Even in the power-supply industry — an industry accustomed to addressing safety, reliability and quality-control issues — there are many vendors who purposely avoid the medical field. Product liability is one reason, as evidenced by disclaimers that certain products not be used in life-supporting equipment.
But despite these hurdles, several power-supply merchants are addressing medical applications. For these companies, the efforts required to design, build and qualify products may be justified by a modest but steadily growing marketplace. A report just issued by Frost & Sullivan projects that the world power-supply market for medical applications will grow from revenues of $350 million in 2005 to $438.1 million in 2012. These numbers represent just a fraction of the overall power-supply market in which the top vendors can exceed $1 billion in annual revenue. Nevertheless, medical applications represent an attractive niche for some vendors because power-supply products, once qualified for use in the applications, can have very long life cycles.
In its report, Frost & Sullivan identifies several factors that are driving growth in the medical power-supply market. One is the rise in a number of target applications such as CAT scans, MRI devices, blood analyzers and patient-monitoring systems for home care. In addition, there are the specific requirements within medical applications that are now increasing demands for high power-supply efficiency, reliability, cost-effectiveness and standards compliance.
According to Frost & Sullivan, one of the factors that could potentially hinder the growth of the medical power-supply field is a lack of awareness among end users of the availability of medical-grade supplies. In some cases, commercial power supplies are being used in applications where medical-grade units should be deployed. Consequently, there is a need to educate end users (equipment manufacturers) about the factors that distinguish medical-grade supplies from standard commercial units. For more information on this report, e-mail [email protected].
Power-supply and component vendors continue to address this issue in various forums with articles and conference papers that discuss specific requirements such as component spacing, insulation and leakage current in medical power supplies. However, the power-supply industry and its customers need to be aware of products that claim to be medical-grade supplies but fail to meet the minimum standards of performance and reliability. In a technical session at the upcoming Power Electronics Technology conference (Oct. 24-26 in Long Beach, Calif.), Kevin Parmenter of Fairchild Semiconductor will pose the question, “Are All Medical Power Supplies the Same?”
Parmenter will examine some of the problems encountered with products that claim to be medical-grade power supplies, but fail to meet the established requirements for safety, and suffer from poor electrical and mechanical designs.
One aspect of these poor designs is the use of inferior components within the power supply. The International Electronics Manufacturing Initiative (iNEMI) is currently addressing this topic. iNEMI recently initiated a project to develop reliability specifications for medical-grade electronic components. The Medical Components Reliability Specifications Project aims to develop testing and use condition guidelines to assure the reliability of electronic components used in medical applications. The project will develop test and extrapolation methodologies that can be used to predict the reliability of components in actual-use conditions and create minimum requirements for components used in implanted or life-critical devices. Although the focus may be on implanted devices, the specifications could benefit power-supply manufacturers as they seek to ensure the reliability of their designs. For more on this project, see www.inemi.org/cms/projects/medical/Medical_Components_Reliability_Specifications.html.
Power-supply designers who participate in such standardization efforts may find opportunities to educate others in the medical electronics field about the critical nature of medical power-supply performance, quality and compliance.