How can we effectively control EMI noise in medical instruments? 】 In today's medical devices are increasingly complex electronic devices, in order to improve the device to monitor, display, assist and warn the patient a series of functions. The latest generation of medical device electronic equipment is smaller and more compact, but it can plug in more monitoring instruments. The biggest design difficulty that comes with it is how can it effectively reduce the interference of external electromagnetic waves on the equipment? The good news is that it has now found problems with EMI and cable noise control in military and satellite systems in confined spaces. The cable and connector experience in military and satellite systems has unexpectedly solved the EMI control problem for the medical device industry. Pave the way. The industry's proven experience with cables and connectors helps to use more secure cables in the medical industry. Lessons learned from the design of cables for military and satellite systems are important because many newer ICU instruments are based on digital signals operating at gigahertz speeds, and close to other electronic instruments. Typically, this will help determine if cables routed within the instrument rack can be disturbed by external electromagnetic waves (receivers that do not need EMI), or if the cable can be an emitter of EMI noise to propagate to other devices. In either case, EMI noise can cause serious problems with the performance of the entire medical device or reduce the accuracy of the instrument to varying degrees. Medical cables and designers have a variety of solutions to control EMI noise in medical instruments. The following lists several current mainstream solutions to EMI noise: 1. Selective filter circuit You can solve the problem of EMI by finding the frequency of the interfering noise and adding a selective filter circuit on the instrument board, or by adding a filter to the connector on the cable harness. Film capacitors and resistors can eliminate unwanted signal noise by grounding near a noise source. However, cables and connectors must be made small enough. If the size is too large, the performance of the coaxial filter circuit will be limited, which will have a certain impact on the performance of electromagnetic interference. 2. Overall shielding The use of braided shields on cables has always been one of the mainstream methods when it comes to isolating electromagnetic waves from external complex environments. It is widely recognized in the industry that weaving is usually the best shielding solution and it can easily provide up to 85dB isolation from external noise. To reduce the number of lines when entering and leaving the system, medical equipment can use hybrid cables and connectors to combine power, signals, and triggers into a single connector and cable system. However, note that inside the connector, there is a power pin on one side and a signal pin on the other side. But more importantly, the cable from each metal circular connector to the main interface connector is a hidden braided shield. Perfume Lotus Tea Perfume Lotus TeaPerfume test YIWU BEAUTYPLUS ART NAIL CO., LTD. , https://www.cn-gangdao.com
August 13, 2023