There are many kinds of medical equipment, from very common standard equipment to very complex equipment. These medical applications can be divided into three categories:
Category 1: General medical equipment.
These products are usually low-risk. Although they are used in some medical means, it is difficult to cause personal injury, such as electronic scales, gauges and dental mirrors.
Category 2: Medical instruments with certain risks.
The risks of these products are higher than those of Category 1 products, but only limited to operation and maintenance risks, such as electric wheelchairs and monitoring instruments.
Category 3: Life-support equipment.
These products are essential and must be manufactured according to the highest standards to ensure their high reliability. Once these life support devices stop or fail, they will lead to serious consequences, such as pacemakers and heart valves. We know that medical devices must meet certain standards and meet some basic standards, whether in function, production or quality system.
Table 1 lists some different key standards and examples:
At the same time, it is important to consider how these standards can be transformed into requirements or considerations that can be directly placed on PCB design (see Table 2).
After evaluating the design elements, we must also consider the manufacturing elements corresponding to medical applications. These factors may directly affect the quality and reliability of PCB. When it comes to security, the elements in Table 3 are very important.
In addition to the above elements, there are many strict standards to be observed.
For example, the cleaning requirements exceed IPC standards, and some manufacturers even require the use of internationally renowned substrate types. The solder mask on the surface of the circuit board and the conductor needs to reach a specific thickness, with clear appearance and high maintenance requirements. When type VI solder mask is needed, the requirement for filling depth of through hole is more stringent.
PCB design for medical applications needs specific components to meet the specific elements of power, signal quality, crosstalk and grounding requirements, but the most important thing is its reliability and safety.
Safety is a key issue, including radiation, electrical performance, thermal performance and mechanical safety, all of which are driven by IPC level 3 standard. Therefore, it is very important to have a reliable manufacturer who can meet these requirements and provide reliable circuit boards for medical applications.
